Documentation/DocBook/media/v4l/controls.xml

   1   <section id="control">
   2     <title>User Controls</title>
   3
   4     <para>Devices typically have a number of user-settable controls
   5 such as brightness, saturation and so on, which would be presented to
   6 the user on a graphical user interface. But, different devices
   7 will have different controls available, and furthermore, the range of
   8 possible values, and the default value will vary from device to
   9 device. The control ioctls provide the information and a mechanism to
  10 create a nice user interface for these controls that will work
  11 correctly with any device.</para>
  12
  13     <para>All controls are accessed using an ID value. V4L2 defines
  14 several IDs for specific purposes. Drivers can also implement their
  15 own custom controls using <constant>V4L2_CID_PRIVATE_BASE</constant>
  16 <footnote><para>The use of <constant>V4L2_CID_PRIVATE_BASE</constant>
  17 is problematic because different drivers may use the same
  18 <constant>V4L2_CID_PRIVATE_BASE</constant> ID for different controls.
  19 This makes it hard to programatically set such controls since the meaning
  20 of the control with that ID is driver dependent. In order to resolve this
  21 drivers use unique IDs and the <constant>V4L2_CID_PRIVATE_BASE</constant>
  22 IDs are mapped to those unique IDs by the kernel. Consider these
  23 <constant>V4L2_CID_PRIVATE_BASE</constant> IDs as aliases to the real
  24 IDs.</para>
  25 <para>Many applications today still use the <constant>V4L2_CID_PRIVATE_BASE</constant>
  26 IDs instead of using &VIDIOC-QUERYCTRL; with the <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>
  27 flag to enumerate all IDs, so support for <constant>V4L2_CID_PRIVATE_BASE</constant>
  28 is still around.</para></footnote>
  29 and higher values. The pre-defined control IDs have the prefix
  30 <constant>V4L2_CID_</constant>, and are listed in <xref
  31 linkend="control-id" />. The ID is used when querying the attributes of
  32 a control, and when getting or setting the current value.</para>
  33
  34     <para>Generally applications should present controls to the user
  35 without assumptions about their purpose. Each control comes with a
  36 name string the user is supposed to understand. When the purpose is
  37 non-intuitive the driver writer should provide a user manual, a user
  38 interface plug-in or a driver specific panel application. Predefined
  39 IDs were introduced to change a few controls programmatically, for
  40 example to mute a device during a channel switch.</para>
  41
  42     <para>Drivers may enumerate different controls after switching
  43 the current video input or output, tuner or modulator, or audio input
  44 or output. Different in the sense of other bounds, another default and
  45 current value, step size or other menu items. A control with a certain
  46 <emphasis>custom</emphasis> ID can also change name and
  47 type.</para>
  48
  49     <para>If a control is not applicable to the current configuration
  50 of the device (for example, it doesn't apply to the current video input)
  51 drivers set the <constant>V4L2_CTRL_FLAG_INACTIVE</constant> flag.</para>
  52
  53     <para>Control values are stored globally, they do not
  54 change when switching except to stay within the reported bounds. They
  55 also do not change &eg; when the device is opened or closed, when the
  56 tuner radio frequency is changed or generally never without
  57 application request.</para>
  58
  59     <para>V4L2 specifies an event mechanism to notify applications
  60 when controls change value (see &VIDIOC-SUBSCRIBE-EVENT;, event
  61 <constant>V4L2_EVENT_CTRL</constant>), panel applications might want to make
  62 use of that in order to always reflect the correct control value.</para>
  63
  64     <para>
  65       All controls use machine endianness.
  66     </para>
  67
  68     <table pgwide="1" frame="none" id="control-id">
  69       <title>Control IDs</title>
  70       <tgroup cols="3">
  71         &cs-def;
  72         <thead>
  73           <row>
  74             <entry>ID</entry>
  75             <entry>Type</entry>
  76             <entry>Description</entry>
  77           </row>
  78         </thead>
  79         <tbody valign="top">
  80           <row>
  81             <entry><constant>V4L2_CID_BASE</constant></entry>
  82             <entry></entry>
  83             <entry>First predefined ID, equal to
  84 <constant>V4L2_CID_BRIGHTNESS</constant>.</entry>
  85           </row>
  86           <row>
  87             <entry><constant>V4L2_CID_USER_BASE</constant></entry>
  88             <entry></entry>
  89             <entry>Synonym of <constant>V4L2_CID_BASE</constant>.</entry>
  90           </row>
  91           <row>
  92             <entry><constant>V4L2_CID_BRIGHTNESS</constant></entry>
  93             <entry>integer</entry>
  94             <entry>Picture brightness, or more precisely, the black
  95 level.</entry>
  96           </row>
  97           <row>
  98             <entry><constant>V4L2_CID_CONTRAST</constant></entry>
  99             <entry>integer</entry>
 100             <entry>Picture contrast or luma gain.</entry>
 101           </row>
 102           <row>
 103             <entry><constant>V4L2_CID_SATURATION</constant></entry>
 104             <entry>integer</entry>
 105             <entry>Picture color saturation or chroma gain.</entry>
 106           </row>
 107           <row>
 108             <entry><constant>V4L2_CID_HUE</constant></entry>
 109             <entry>integer</entry>
 110             <entry>Hue or color balance.</entry>
 111           </row>
 112           <row>
 113             <entry><constant>V4L2_CID_AUDIO_VOLUME</constant></entry>
 114             <entry>integer</entry>
 115             <entry>Overall audio volume. Note some drivers also
 116 provide an OSS or ALSA mixer interface.</entry>
 117           </row>
 118           <row>
 119             <entry><constant>V4L2_CID_AUDIO_BALANCE</constant></entry>
 120             <entry>integer</entry>
 121             <entry>Audio stereo balance. Minimum corresponds to all
 122 the way left, maximum to right.</entry>
 123           </row>
 124           <row>
 125             <entry><constant>V4L2_CID_AUDIO_BASS</constant></entry>
 126             <entry>integer</entry>
 127             <entry>Audio bass adjustment.</entry>
 128           </row>
 129           <row>
 130             <entry><constant>V4L2_CID_AUDIO_TREBLE</constant></entry>
 131             <entry>integer</entry>
 132             <entry>Audio treble adjustment.</entry>
 133           </row>
 134           <row>
 135             <entry><constant>V4L2_CID_AUDIO_MUTE</constant></entry>
 136             <entry>boolean</entry>
 137             <entry>Mute audio, &ie; set the volume to zero, however
 138 without affecting <constant>V4L2_CID_AUDIO_VOLUME</constant>. Like
 139 ALSA drivers, V4L2 drivers must mute at load time to avoid excessive
 140 noise. Actually the entire device should be reset to a low power
 141 consumption state.</entry>
 142           </row>
 143           <row>
 144             <entry><constant>V4L2_CID_AUDIO_LOUDNESS</constant></entry>
 145             <entry>boolean</entry>
 146             <entry>Loudness mode (bass boost).</entry>
 147           </row>
 148           <row>
 149             <entry><constant>V4L2_CID_BLACK_LEVEL</constant></entry>
 150             <entry>integer</entry>
 151             <entry>Another name for brightness (not a synonym of
 152 <constant>V4L2_CID_BRIGHTNESS</constant>). This control is deprecated
 153 and should not be used in new drivers and applications.</entry>
 154           </row>
 155           <row>
 156             <entry><constant>V4L2_CID_AUTO_WHITE_BALANCE</constant></entry>
 157             <entry>boolean</entry>
 158             <entry>Automatic white balance (cameras).</entry>
 159           </row>
 160           <row>
 161             <entry><constant>V4L2_CID_DO_WHITE_BALANCE</constant></entry>
 162             <entry>button</entry>
 163             <entry>This is an action control. When set (the value is
 164 ignored), the device will do a white balance and then hold the current
 165 setting. Contrast this with the boolean
 166 <constant>V4L2_CID_AUTO_WHITE_BALANCE</constant>, which, when
 167 activated, keeps adjusting the white balance.</entry>
 168           </row>
 169           <row>
 170             <entry><constant>V4L2_CID_RED_BALANCE</constant></entry>
 171             <entry>integer</entry>
 172             <entry>Red chroma balance.</entry>
 173           </row>
 174           <row>
 175             <entry><constant>V4L2_CID_BLUE_BALANCE</constant></entry>
 176             <entry>integer</entry>
 177             <entry>Blue chroma balance.</entry>
 178           </row>
 179           <row>
 180             <entry><constant>V4L2_CID_GAMMA</constant></entry>
 181             <entry>integer</entry>
 182             <entry>Gamma adjust.</entry>
 183           </row>
 184           <row>
 185             <entry><constant>V4L2_CID_WHITENESS</constant></entry>
 186             <entry>integer</entry>
 187             <entry>Whiteness for grey-scale devices. This is a synonym
 188 for <constant>V4L2_CID_GAMMA</constant>. This control is deprecated
 189 and should not be used in new drivers and applications.</entry>
 190           </row>
 191           <row>
 192             <entry><constant>V4L2_CID_EXPOSURE</constant></entry>
 193             <entry>integer</entry>
 194             <entry>Exposure (cameras). [Unit?]</entry>
 195           </row>
 196           <row>
 197             <entry><constant>V4L2_CID_AUTOGAIN</constant></entry>
 198             <entry>boolean</entry>
 199             <entry>Automatic gain/exposure control.</entry>
 200           </row>
 201           <row>
 202             <entry><constant>V4L2_CID_GAIN</constant></entry>
 203             <entry>integer</entry>
 204             <entry>Gain control.</entry>
 205           </row>
 206           <row>
 207             <entry><constant>V4L2_CID_HFLIP</constant></entry>
 208             <entry>boolean</entry>
 209             <entry>Mirror the picture horizontally.</entry>
 210           </row>
 211           <row>
 212             <entry><constant>V4L2_CID_VFLIP</constant></entry>
 213             <entry>boolean</entry>
 214             <entry>Mirror the picture vertically.</entry>
 215           </row>
 216           <row id="v4l2-power-line-frequency">
 217             <entry><constant>V4L2_CID_POWER_LINE_FREQUENCY</constant></entry>
 218             <entry>enum</entry>
 219             <entry>Enables a power line frequency filter to avoid
 220 flicker. Possible values for <constant>enum v4l2_power_line_frequency</constant> are:
 221 <constant>V4L2_CID_POWER_LINE_FREQUENCY_DISABLED</constant> (0),
 222 <constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1),
 223 <constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2) and
 224 <constant>V4L2_CID_POWER_LINE_FREQUENCY_AUTO</constant> (3).</entry>
 225           </row>
 226           <row>
 227             <entry><constant>V4L2_CID_HUE_AUTO</constant></entry>
 228             <entry>boolean</entry>
 229             <entry>Enables automatic hue control by the device. The
 230 effect of setting <constant>V4L2_CID_HUE</constant> while automatic
 231 hue control is enabled is undefined, drivers should ignore such
 232 request.</entry>
 233           </row>
 234           <row>
 235             <entry><constant>V4L2_CID_WHITE_BALANCE_TEMPERATURE</constant></entry>
 236             <entry>integer</entry>
 237             <entry>This control specifies the white balance settings
 238 as a color temperature in Kelvin. A driver should have a minimum of
 239 2800 (incandescent) to 6500 (daylight). For more information about
 240 color temperature see <ulink
 241 url="http://en.wikipedia.org/wiki/Color_temperature">Wikipedia</ulink>.</entry>
 242           </row>
 243           <row>
 244             <entry><constant>V4L2_CID_SHARPNESS</constant></entry>
 245             <entry>integer</entry>
 246             <entry>Adjusts the sharpness filters in a camera. The
 247 minimum value disables the filters, higher values give a sharper
 248 picture.</entry>
 249           </row>
 250           <row>
 251             <entry><constant>V4L2_CID_BACKLIGHT_COMPENSATION</constant></entry>
 252             <entry>integer</entry>
 253             <entry>Adjusts the backlight compensation in a camera. The
 254 minimum value disables backlight compensation.</entry>
 255           </row>
 256           <row>
 257             <entry><constant>V4L2_CID_CHROMA_AGC</constant></entry>
 258             <entry>boolean</entry>
 259             <entry>Chroma automatic gain control.</entry>
 260           </row>
 261           <row>
 262             <entry><constant>V4L2_CID_CHROMA_GAIN</constant></entry>
 263             <entry>integer</entry>
 264             <entry>Adjusts the Chroma gain control (for use when chroma AGC
 265             is disabled).</entry>
 266           </row>
 267           <row>
 268             <entry><constant>V4L2_CID_COLOR_KILLER</constant></entry>
 269             <entry>boolean</entry>
 270             <entry>Enable the color killer (&ie; force a black &amp; white image in case of a weak video signal).</entry>
 271           </row>
 272           <row id="v4l2-colorfx">
 273             <entry><constant>V4L2_CID_COLORFX</constant></entry>
 274             <entry>enum</entry>
 275             <entry>Selects a color effect. The following values are defined:
 276             </entry>
 277           </row><row>
 278           <entry></entry>
 279           <entry></entry>
 280             <entrytbl spanname="descr" cols="2">
 281               <tbody valign="top">
 282                 <row>
 283                   <entry><constant>V4L2_COLORFX_NONE</constant>&nbsp;</entry>
 284                   <entry>Color effect is disabled.</entry>
 285                 </row>
 286                 <row>
 287                   <entry><constant>V4L2_COLORFX_ANTIQUE</constant>&nbsp;</entry>
 288                   <entry>An aging (old photo) effect.</entry>
 289                 </row>
 290                 <row>
 291                   <entry><constant>V4L2_COLORFX_ART_FREEZE</constant>&nbsp;</entry>
 292                   <entry>Frost color effect.</entry>
 293                 </row>
 294                 <row>
 295                   <entry><constant>V4L2_COLORFX_AQUA</constant>&nbsp;</entry>
 296                   <entry>Water color, cool tone.</entry>
 297                 </row>
 298                 <row>
 299                   <entry><constant>V4L2_COLORFX_BW</constant>&nbsp;</entry>
 300                   <entry>Black and white.</entry>
 301                 </row>
 302                 <row>
 303                   <entry><constant>V4L2_COLORFX_EMBOSS</constant>&nbsp;</entry>
 304                   <entry>Emboss, the highlights and shadows replace light/dark boundaries
 305                   and low contrast areas are set to a gray background.</entry>
 306                 </row>
 307                 <row>
 308                   <entry><constant>V4L2_COLORFX_GRASS_GREEN</constant>&nbsp;</entry>
 309                   <entry>Grass green.</entry>
 310                 </row>
 311                 <row>
 312                   <entry><constant>V4L2_COLORFX_NEGATIVE</constant>&nbsp;</entry>
 313                   <entry>Negative.</entry>
 314                 </row>
 315                 <row>
 316                   <entry><constant>V4L2_COLORFX_SEPIA</constant>&nbsp;</entry>
 317                   <entry>Sepia tone.</entry>
 318                 </row>
 319                 <row>
 320                   <entry><constant>V4L2_COLORFX_SKETCH</constant>&nbsp;</entry>
 321                   <entry>Sketch.</entry>
 322                 </row>
 323                 <row>
 324                   <entry><constant>V4L2_COLORFX_SKIN_WHITEN</constant>&nbsp;</entry>
 325                   <entry>Skin whiten.</entry>
 326                 </row>
 327                 <row>
 328                   <entry><constant>V4L2_COLORFX_SKY_BLUE</constant>&nbsp;</entry>
 329                   <entry>Sky blue.</entry>
 330                 </row>
 331                 <row>
 332                   <entry><constant>V4L2_COLORFX_SOLARIZATION</constant>&nbsp;</entry>
 333                   <entry>Solarization, the image is partially reversed in tone,
 334                   only color values above or below a certain threshold are inverted.
 335                   </entry>
 336                 </row>
 337                 <row>
 338                   <entry><constant>V4L2_COLORFX_SILHOUETTE</constant>&nbsp;</entry>
 339                   <entry>Silhouette (outline).</entry>
 340                 </row>
 341                 <row>
 342                   <entry><constant>V4L2_COLORFX_VIVID</constant>&nbsp;</entry>
 343                   <entry>Vivid colors.</entry>
 344                 </row>
 345                 <row>
 346                   <entry><constant>V4L2_COLORFX_SET_CBCR</constant>&nbsp;</entry>
 347                   <entry>The Cb and Cr chroma components are replaced by fixed
 348                   coefficients determined by <constant>V4L2_CID_COLORFX_CBCR</constant>
 349                   control.</entry>
 350                 </row>
 351               </tbody>
 352             </entrytbl>
 353           </row>
 354           <row>
 355             <entry><constant>V4L2_CID_COLORFX_CBCR</constant></entry>
 356             <entry>integer</entry>
 357             <entry>Determines the Cb and Cr coefficients for <constant>V4L2_COLORFX_SET_CBCR</constant>
 358             color effect. Bits [7:0] of the supplied 32 bit value are interpreted as
 359             Cr component, bits [15:8] as Cb component and bits [31:16] must be zero.
 360           </entry>
 361           </row>
 362           <row>
 363             <entry><constant>V4L2_CID_AUTOBRIGHTNESS</constant></entry>
 364             <entry>boolean</entry>
 365             <entry>Enable Automatic Brightness.</entry>
 366           </row>
 367           <row>
 368             <entry><constant>V4L2_CID_ROTATE</constant></entry>
 369             <entry>integer</entry>
 370             <entry>Rotates the image by specified angle. Common angles are 90,
 371             270 and 180. Rotating the image to 90 and 270 will reverse the height
 372             and width of the display window. It is necessary to set the new height and
 373             width of the picture using the &VIDIOC-S-FMT; ioctl according to
 374             the rotation angle selected.</entry>
 375           </row>
 376           <row>
 377             <entry><constant>V4L2_CID_BG_COLOR</constant></entry>
 378             <entry>integer</entry>
 379             <entry>Sets the background color on the current output device.
 380             Background color needs to be specified in the RGB24 format. The
 381             supplied 32 bit value is interpreted as bits 0-7 Red color information,
 382             bits 8-15 Green color information, bits 16-23 Blue color
 383             information and bits 24-31 must be zero.</entry>
 384           </row>
 385           <row>
 386             <entry><constant>V4L2_CID_ILLUMINATORS_1</constant>
 387                 <constant>V4L2_CID_ILLUMINATORS_2</constant></entry>
 388             <entry>boolean</entry>
 389             <entry>Switch on or off the illuminator 1 or 2 of the device
 390                 (usually a microscope).</entry>
 391           </row>
 392           <row>
 393             <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_CAPTURE</constant></entry>
 394             <entry>integer</entry>
 395             <entry>This is a read-only control that can be read by the application
 396 and used as a hint to determine the number of CAPTURE buffers to pass to REQBUFS.
 397 The value is the minimum number of CAPTURE buffers that is necessary for hardware
 398 to work.</entry>
 399           </row>
 400           <row>
 401             <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_OUTPUT</constant></entry>
 402             <entry>integer</entry>
 403             <entry>This is a read-only control that can be read by the application
 404 and used as a hint to determine the number of OUTPUT buffers to pass to REQBUFS.
 405 The value is the minimum number of OUTPUT buffers that is necessary for hardware
 406 to work.</entry>
 407           </row>
 408           <row id="v4l2-alpha-component">
 409             <entry><constant>V4L2_CID_ALPHA_COMPONENT</constant></entry>
 410             <entry>integer</entry>
 411             <entry> Sets the alpha color component on the capture device or on
 412             the capture buffer queue of a mem-to-mem device. When a mem-to-mem
 413             device produces frame format that includes an alpha component
 414             (e.g. <link linkend="rgb-formats">packed RGB image formats</link>)
 415             and the alpha value is not defined by the mem-to-mem input data
 416             this control lets you select the alpha component value of all
 417             pixels. It is applicable to any pixel format that contains an alpha
 418             component.
 419             </entry>
 420           </row>
 421           <row>
 422             <entry><constant>V4L2_CID_LASTP1</constant></entry>
 423             <entry></entry>
 424             <entry>End of the predefined control IDs (currently
 425               <constant>V4L2_CID_ALPHA_COMPONENT</constant> + 1).</entry>
 426           </row>
 427           <row>
 428             <entry><constant>V4L2_CID_PRIVATE_BASE</constant></entry>
 429             <entry></entry>
 430             <entry>ID of the first custom (driver specific) control.
 431 Applications depending on particular custom controls should check the
 432 driver name and version, see <xref linkend="querycap" />.</entry>
 433           </row>
 434         </tbody>
 435       </tgroup>
 436     </table>
 437
 438     <para>Applications can enumerate the available controls with the
 439 &VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls, get and set a
 440 control value with the &VIDIOC-G-CTRL; and &VIDIOC-S-CTRL; ioctls.
 441 Drivers must implement <constant>VIDIOC_QUERYCTRL</constant>,
 442 <constant>VIDIOC_G_CTRL</constant> and
 443 <constant>VIDIOC_S_CTRL</constant> when the device has one or more
 444 controls, <constant>VIDIOC_QUERYMENU</constant> when it has one or
 445 more menu type controls.</para>
 446
 447     <example id="enum_all_controls">
 448       <title>Enumerating all user controls</title>
 449
 450       <programlisting>
 451 &v4l2-queryctrl; queryctrl;
 452 &v4l2-querymenu; querymenu;
 453
 454 static void enumerate_menu(void)
 455 {
 456         printf("  Menu items:\n");
 457
 458         memset(&amp;querymenu, 0, sizeof(querymenu));
 459         querymenu.id = queryctrl.id;
 460
 461         for (querymenu.index = queryctrl.minimum;
 462              querymenu.index &lt;= queryctrl.maximum;
 463              querymenu.index++) {
 464                 if (0 == ioctl(fd, &VIDIOC-QUERYMENU;, &amp;querymenu)) {
 465                         printf("  %s\n", querymenu.name);
 466                 }
 467         }
 468 }
 469
 470 memset(&amp;queryctrl, 0, sizeof(queryctrl));
 471
 472 for (queryctrl.id = V4L2_CID_BASE;
 473      queryctrl.id &lt; V4L2_CID_LASTP1;
 474      queryctrl.id++) {
 475         if (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 476                 if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED)
 477                         continue;
 478
 479                 printf("Control %s\n", queryctrl.name);
 480
 481                 if (queryctrl.type == V4L2_CTRL_TYPE_MENU)
 482                         enumerate_menu();
 483         } else {
 484                 if (errno == EINVAL)
 485                         continue;
 486
 487                 perror("VIDIOC_QUERYCTRL");
 488                 exit(EXIT_FAILURE);
 489         }
 490 }
 491
 492 for (queryctrl.id = V4L2_CID_PRIVATE_BASE;;
 493      queryctrl.id++) {
 494         if (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 495                 if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED)
 496                         continue;
 497
 498                 printf("Control %s\n", queryctrl.name);
 499
 500                 if (queryctrl.type == V4L2_CTRL_TYPE_MENU)
 501                         enumerate_menu();
 502         } else {
 503                 if (errno == EINVAL)
 504                         break;
 505
 506                 perror("VIDIOC_QUERYCTRL");
 507                 exit(EXIT_FAILURE);
 508         }
 509 }
 510 </programlisting>
 511     </example>
 512
 513     <example>
 514       <title>Enumerating all user controls (alternative)</title>
 515         <programlisting>
 516 memset(&amp;queryctrl, 0, sizeof(queryctrl));
 517
 518 queryctrl.id = V4L2_CTRL_CLASS_USER | V4L2_CTRL_FLAG_NEXT_CTRL;
 519 while (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 520         if (V4L2_CTRL_ID2CLASS(queryctrl.id) != V4L2_CTRL_CLASS_USER)
 521                 break;
 522         if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED)
 523                 continue;
 524
 525         printf("Control %s\n", queryctrl.name);
 526
 527         if (queryctrl.type == V4L2_CTRL_TYPE_MENU)
 528                 enumerate_menu();
 529
 530         queryctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
 531 }
 532 if (errno != EINVAL) {
 533         perror("VIDIOC_QUERYCTRL");
 534         exit(EXIT_FAILURE);
 535 }
 536 </programlisting>
 537     </example>
 538
 539     <example>
 540       <title>Changing controls</title>
 541
 542       <programlisting>
 543 &v4l2-queryctrl; queryctrl;
 544 &v4l2-control; control;
 545
 546 memset(&amp;queryctrl, 0, sizeof(queryctrl));
 547 queryctrl.id = V4L2_CID_BRIGHTNESS;
 548
 549 if (-1 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 550         if (errno != EINVAL) {
 551                 perror("VIDIOC_QUERYCTRL");
 552                 exit(EXIT_FAILURE);
 553         } else {
 554                 printf("V4L2_CID_BRIGHTNESS is not supported\n");
 555         }
 556 } else if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED) {
 557         printf("V4L2_CID_BRIGHTNESS is not supported\n");
 558 } else {
 559         memset(&amp;control, 0, sizeof (control));
 560         control.id = V4L2_CID_BRIGHTNESS;
 561         control.value = queryctrl.default_value;
 562
 563         if (-1 == ioctl(fd, &VIDIOC-S-CTRL;, &amp;control)) {
 564                 perror("VIDIOC_S_CTRL");
 565                 exit(EXIT_FAILURE);
 566         }
 567 }
 568
 569 memset(&amp;control, 0, sizeof(control));
 570 control.id = V4L2_CID_CONTRAST;
 571
 572 if (0 == ioctl(fd, &VIDIOC-G-CTRL;, &amp;control)) {
 573         control.value += 1;
 574
 575         /* The driver may clamp the value or return ERANGE, ignored here */
 576
 577         if (-1 == ioctl(fd, &VIDIOC-S-CTRL;, &amp;control)
 578             &amp;&amp; errno != ERANGE) {
 579                 perror("VIDIOC_S_CTRL");
 580                 exit(EXIT_FAILURE);
 581         }
 582 /* Ignore if V4L2_CID_CONTRAST is unsupported */
 583 } else if (errno != EINVAL) {
 584         perror("VIDIOC_G_CTRL");
 585         exit(EXIT_FAILURE);
 586 }
 587
 588 control.id = V4L2_CID_AUDIO_MUTE;
 589 control.value = 1; /* silence */
 590
 591 /* Errors ignored */
 592 ioctl(fd, VIDIOC_S_CTRL, &amp;control);
 593 </programlisting>
 594     </example>
 595   </section>
 596
 597   <section id="extended-controls">
 598     <title>Extended Controls</title>
 599
 600     <section>
 601       <title>Introduction</title>
 602
 603       <para>The control mechanism as originally designed was meant
 604 to be used for user settings (brightness, saturation, etc). However,
 605 it turned out to be a very useful model for implementing more
 606 complicated driver APIs where each driver implements only a subset of
 607 a larger API.</para>
 608
 609       <para>The MPEG encoding API was the driving force behind
 610 designing and implementing this extended control mechanism: the MPEG
 611 standard is quite large and the currently supported hardware MPEG
 612 encoders each only implement a subset of this standard. Further more,
 613 many parameters relating to how the video is encoded into an MPEG
 614 stream are specific to the MPEG encoding chip since the MPEG standard
 615 only defines the format of the resulting MPEG stream, not how the
 616 video is actually encoded into that format.</para>
 617
 618       <para>Unfortunately, the original control API lacked some
 619 features needed for these new uses and so it was extended into the
 620 (not terribly originally named) extended control API.</para>
 621
 622       <para>Even though the MPEG encoding API was the first effort
 623 to use the Extended Control API, nowadays there are also other classes
 624 of Extended Controls, such as Camera Controls and FM Transmitter Controls.
 625 The Extended Controls API as well as all Extended Controls classes are
 626 described in the following text.</para>
 627     </section>
 628
 629     <section>
 630       <title>The Extended Control API</title>
 631
 632       <para>Three new ioctls are available: &VIDIOC-G-EXT-CTRLS;,
 633 &VIDIOC-S-EXT-CTRLS; and &VIDIOC-TRY-EXT-CTRLS;. These ioctls act on
 634 arrays of controls (as opposed to the &VIDIOC-G-CTRL; and
 635 &VIDIOC-S-CTRL; ioctls that act on a single control). This is needed
 636 since it is often required to atomically change several controls at
 637 once.</para>
 638
 639       <para>Each of the new ioctls expects a pointer to a
 640 &v4l2-ext-controls;. This structure contains a pointer to the control
 641 array, a count of the number of controls in that array and a control
 642 class. Control classes are used to group similar controls into a
 643 single class. For example, control class
 644 <constant>V4L2_CTRL_CLASS_USER</constant> contains all user controls
 645 (&ie; all controls that can also be set using the old
 646 <constant>VIDIOC_S_CTRL</constant> ioctl). Control class
 647 <constant>V4L2_CTRL_CLASS_MPEG</constant> contains all controls
 648 relating to MPEG encoding, etc.</para>
 649
 650       <para>All controls in the control array must belong to the
 651 specified control class. An error is returned if this is not the
 652 case.</para>
 653
 654       <para>It is also possible to use an empty control array (count
 655 == 0) to check whether the specified control class is
 656 supported.</para>
 657
 658       <para>The control array is a &v4l2-ext-control; array. The
 659 <structname>v4l2_ext_control</structname> structure is very similar to
 660 &v4l2-control;, except for the fact that it also allows for 64-bit
 661 values and pointers to be passed.</para>
 662
 663       <para>It is important to realize that due to the flexibility of
 664 controls it is necessary to check whether the control you want to set
 665 actually is supported in the driver and what the valid range of values
 666 is. So use the &VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls to
 667 check this. Also note that it is possible that some of the menu
 668 indices in a control of type <constant>V4L2_CTRL_TYPE_MENU</constant>
 669 may not be supported (<constant>VIDIOC_QUERYMENU</constant> will
 670 return an error). A good example is the list of supported MPEG audio
 671 bitrates. Some drivers only support one or two bitrates, others
 672 support a wider range.</para>
 673
 674       <para>
 675         All controls use machine endianness.
 676       </para>
 677     </section>
 678
 679     <section>
 680       <title>Enumerating Extended Controls</title>
 681
 682       <para>The recommended way to enumerate over the extended
 683 controls is by using &VIDIOC-QUERYCTRL; in combination with the
 684 <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag:</para>
 685
 686       <informalexample>
 687         <programlisting>
 688 &v4l2-queryctrl; qctrl;
 689
 690 qctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL;
 691 while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &amp;qctrl)) {
 692         /* ... */
 693         qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
 694 }
 695 </programlisting>
 696       </informalexample>
 697
 698       <para>The initial control ID is set to 0 ORed with the
 699 <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag. The
 700 <constant>VIDIOC_QUERYCTRL</constant> ioctl will return the first
 701 control with a higher ID than the specified one. When no such controls
 702 are found an error is returned.</para>
 703
 704       <para>If you want to get all controls within a specific control
 705 class, then you can set the initial
 706 <structfield>qctrl.id</structfield> value to the control class and add
 707 an extra check to break out of the loop when a control of another
 708 control class is found:</para>
 709
 710       <informalexample>
 711         <programlisting>
 712 qctrl.id = V4L2_CTRL_CLASS_MPEG | V4L2_CTRL_FLAG_NEXT_CTRL;
 713 while (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;qctrl)) {
 714         if (V4L2_CTRL_ID2CLASS(qctrl.id) != V4L2_CTRL_CLASS_MPEG)
 715                 break;
 716                 /* ... */
 717         qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
 718 }
 719 </programlisting>
 720       </informalexample>
 721
 722       <para>The 32-bit <structfield>qctrl.id</structfield> value is
 723 subdivided into three bit ranges: the top 4 bits are reserved for
 724 flags (&eg; <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>) and are not
 725 actually part of the ID. The remaining 28 bits form the control ID, of
 726 which the most significant 12 bits define the control class and the
 727 least significant 16 bits identify the control within the control
 728 class. It is guaranteed that these last 16 bits are always non-zero
 729 for controls. The range of 0x1000 and up are reserved for
 730 driver-specific controls. The macro
 731 <constant>V4L2_CTRL_ID2CLASS(id)</constant> returns the control class
 732 ID based on a control ID.</para>
 733
 734       <para>If the driver does not support extended controls, then
 735 <constant>VIDIOC_QUERYCTRL</constant> will fail when used in
 736 combination with <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>. In
 737 that case the old method of enumerating control should be used (see
 738 <xref linkend="enum_all_controls" />). But if it is supported, then it is guaranteed to enumerate over
 739 all controls, including driver-private controls.</para>
 740     </section>
 741
 742     <section>
 743       <title>Creating Control Panels</title>
 744
 745       <para>It is possible to create control panels for a graphical
 746 user interface where the user can select the various controls.
 747 Basically you will have to iterate over all controls using the method
 748 described above. Each control class starts with a control of type
 749 <constant>V4L2_CTRL_TYPE_CTRL_CLASS</constant>.
 750 <constant>VIDIOC_QUERYCTRL</constant> will return the name of this
 751 control class which can be used as the title of a tab page within a
 752 control panel.</para>
 753
 754       <para>The flags field of &v4l2-queryctrl; also contains hints on
 755 the behavior of the control. See the &VIDIOC-QUERYCTRL; documentation
 756 for more details.</para>
 757     </section>
 758
 759     <section id="mpeg-controls">
 760       <title>Codec Control Reference</title>
 761
 762       <para>Below all controls within the Codec control class are
 763 described. First the generic controls, then controls specific for
 764 certain hardware.</para>
 765
 766       <para>Note: These controls are applicable to all codecs and
 767 not just MPEG. The defines are prefixed with V4L2_CID_MPEG/V4L2_MPEG
 768 as the controls were originally made for MPEG codecs and later
 769 extended to cover all encoding formats.</para>
 770
 771       <section>
 772         <title>Generic Codec Controls</title>
 773
 774         <table pgwide="1" frame="none" id="mpeg-control-id">
 775           <title>Codec Control IDs</title>
 776           <tgroup cols="4">
 777             <colspec colname="c1" colwidth="1*" />
 778             <colspec colname="c2" colwidth="6*" />
 779             <colspec colname="c3" colwidth="2*" />
 780             <colspec colname="c4" colwidth="6*" />
 781             <spanspec namest="c1" nameend="c2" spanname="id" />
 782             <spanspec namest="c2" nameend="c4" spanname="descr" />
 783             <thead>
 784               <row>
 785                 <entry spanname="id" align="left">ID</entry>
 786                 <entry align="left">Type</entry>
 787               </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
 788               </row>
 789             </thead>
 790             <tbody valign="top">
 791               <row><entry></entry></row>
 792               <row>
 793                 <entry spanname="id"><constant>V4L2_CID_MPEG_CLASS</constant>&nbsp;</entry>
 794                 <entry>class</entry>
 795               </row><row><entry spanname="descr">The Codec class
 796 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
 797 description of this control class. This description can be used as the
 798 caption of a Tab page in a GUI, for example.</entry>
 799               </row>
 800               <row><entry></entry></row>
 801               <row id="v4l2-mpeg-stream-type">
 802                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_TYPE</constant>&nbsp;</entry>
 803                 <entry>enum&nbsp;v4l2_mpeg_stream_type</entry>
 804               </row><row><entry spanname="descr">The MPEG-1, -2 or -4
 805 output stream type. One cannot assume anything here. Each hardware
 806 MPEG encoder tends to support different subsets of the available MPEG
 807 stream types. This control is specific to multiplexed MPEG streams.
 808 The currently defined stream types are:</entry>
 809               </row>
 810               <row>
 811                 <entrytbl spanname="descr" cols="2">
 812                   <tbody valign="top">
 813                     <row>
 814                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_PS</constant>&nbsp;</entry>
 815                       <entry>MPEG-2 program stream</entry>
 816                     </row>
 817                     <row>
 818                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_TS</constant>&nbsp;</entry>
 819                       <entry>MPEG-2 transport stream</entry>
 820                     </row>
 821                     <row>
 822                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_SS</constant>&nbsp;</entry>
 823                       <entry>MPEG-1 system stream</entry>
 824                     </row>
 825                     <row>
 826                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_DVD</constant>&nbsp;</entry>
 827                       <entry>MPEG-2 DVD-compatible stream</entry>
 828                     </row>
 829                     <row>
 830                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_VCD</constant>&nbsp;</entry>
 831                       <entry>MPEG-1 VCD-compatible stream</entry>
 832                     </row>
 833                     <row>
 834                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD</constant>&nbsp;</entry>
 835                       <entry>MPEG-2 SVCD-compatible stream</entry>
 836                     </row>
 837                   </tbody>
 838                 </entrytbl>
 839               </row>
 840               <row><entry></entry></row>
 841               <row>
 842                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PMT</constant>&nbsp;</entry>
 843                 <entry>integer</entry>
 844               </row><row><entry spanname="descr">Program Map Table
 845 Packet ID for the MPEG transport stream (default 16)</entry>
 846               </row>
 847               <row><entry></entry></row>
 848               <row>
 849                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_AUDIO</constant>&nbsp;</entry>
 850                 <entry>integer</entry>
 851               </row><row><entry spanname="descr">Audio Packet ID for
 852 the MPEG transport stream (default 256)</entry>
 853               </row>
 854               <row><entry></entry></row>
 855               <row>
 856                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_VIDEO</constant>&nbsp;</entry>
 857                 <entry>integer</entry>
 858               </row><row><entry spanname="descr">Video Packet ID for
 859 the MPEG transport stream (default 260)</entry>
 860               </row>
 861               <row><entry></entry></row>
 862               <row>
 863                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PCR</constant>&nbsp;</entry>
 864                 <entry>integer</entry>
 865               </row><row><entry spanname="descr">Packet ID for the
 866 MPEG transport stream carrying PCR fields (default 259)</entry>
 867               </row>
 868               <row><entry></entry></row>
 869               <row>
 870                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_AUDIO</constant>&nbsp;</entry>
 871                 <entry>integer</entry>
 872               </row><row><entry spanname="descr">Audio ID for MPEG
 873 PES</entry>
 874               </row>
 875               <row><entry></entry></row>
 876               <row>
 877                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_VIDEO</constant>&nbsp;</entry>
 878                 <entry>integer</entry>
 879               </row><row><entry spanname="descr">Video ID for MPEG
 880 PES</entry>
 881               </row>
 882               <row><entry></entry></row>
 883               <row id="v4l2-mpeg-stream-vbi-fmt">
 884                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_VBI_FMT</constant>&nbsp;</entry>
 885                 <entry>enum&nbsp;v4l2_mpeg_stream_vbi_fmt</entry>
 886               </row><row><entry spanname="descr">Some cards can embed
 887 VBI data (&eg; Closed Caption, Teletext) into the MPEG stream. This
 888 control selects whether VBI data should be embedded, and if so, what
 889 embedding method should be used. The list of possible VBI formats
 890 depends on the driver. The currently defined VBI format types
 891 are:</entry>
 892               </row>
 893               <row>
 894                 <entrytbl spanname="descr" cols="2">
 895                   <tbody valign="top">
 896                     <row>
 897                       <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_NONE</constant>&nbsp;</entry>
 898                       <entry>No VBI in the MPEG stream</entry>
 899                     </row>
 900                     <row>
 901                       <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant>&nbsp;</entry>
 902                       <entry>VBI in private packets, IVTV format (documented
 903 in the kernel sources in the file <filename>Documentation/video4linux/cx2341x/README.vbi</filename>)</entry>
 904                     </row>
 905                   </tbody>
 906                 </entrytbl>
 907               </row>
 908               <row><entry></entry></row>
 909               <row id="v4l2-mpeg-audio-sampling-freq">
 910                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ</constant>&nbsp;</entry>
 911                 <entry>enum&nbsp;v4l2_mpeg_audio_sampling_freq</entry>
 912               </row><row><entry spanname="descr">MPEG Audio sampling
 913 frequency. Possible values are:</entry>
 914               </row>
 915               <row>
 916                 <entrytbl spanname="descr" cols="2">
 917                   <tbody valign="top">
 918                     <row>
 919                       <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100</constant>&nbsp;</entry>
 920                       <entry>44.1 kHz</entry>
 921                     </row>
 922                     <row>
 923                       <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000</constant>&nbsp;</entry>
 924                       <entry>48 kHz</entry>
 925                     </row>
 926                     <row>
 927                       <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000</constant>&nbsp;</entry>
 928                       <entry>32 kHz</entry>
 929                     </row>
 930                   </tbody>
 931                 </entrytbl>
 932               </row>
 933               <row><entry></entry></row>
 934               <row id="v4l2-mpeg-audio-encoding">
 935                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_ENCODING</constant>&nbsp;</entry>
 936                 <entry>enum&nbsp;v4l2_mpeg_audio_encoding</entry>
 937               </row><row><entry spanname="descr">MPEG Audio encoding.
 938 This control is specific to multiplexed MPEG streams.
 939 Possible values are:</entry>
 940               </row>
 941               <row>
 942                 <entrytbl spanname="descr" cols="2">
 943                   <tbody valign="top">
 944                     <row>
 945                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_1</constant>&nbsp;</entry>
 946                       <entry>MPEG-1/2 Layer I encoding</entry>
 947                     </row>
 948                     <row>
 949                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_2</constant>&nbsp;</entry>
 950                       <entry>MPEG-1/2 Layer II encoding</entry>
 951                     </row>
 952                     <row>
 953                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_3</constant>&nbsp;</entry>
 954                       <entry>MPEG-1/2 Layer III encoding</entry>
 955                     </row>
 956                     <row>
 957                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AAC</constant>&nbsp;</entry>
 958                       <entry>MPEG-2/4 AAC (Advanced Audio Coding)</entry>
 959                     </row>
 960                     <row>
 961                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AC3</constant>&nbsp;</entry>
 962                       <entry>AC-3 aka ATSC A/52 encoding</entry>
 963                     </row>
 964                   </tbody>
 965                 </entrytbl>
 966               </row>
 967               <row><entry></entry></row>
 968               <row id="v4l2-mpeg-audio-l1-bitrate">
 969                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L1_BITRATE</constant>&nbsp;</entry>
 970                 <entry>enum&nbsp;v4l2_mpeg_audio_l1_bitrate</entry>
 971               </row><row><entry spanname="descr">MPEG-1/2 Layer I bitrate.
 972 Possible values are:</entry>
 973               </row>
 974               <row>
 975                 <entrytbl spanname="descr" cols="2">
 976                   <tbody valign="top">
 977                     <row>
 978                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_32K</constant>&nbsp;</entry>
 979                       <entry>32 kbit/s</entry></row>
 980                     <row>
 981                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_64K</constant>&nbsp;</entry>
 982                       <entry>64 kbit/s</entry>
 983                     </row>
 984                     <row>
 985                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_96K</constant>&nbsp;</entry>
 986                       <entry>96 kbit/s</entry>
 987                     </row>
 988                     <row>
 989                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_128K</constant>&nbsp;</entry>
 990                       <entry>128 kbit/s</entry>
 991                     </row>
 992                     <row>
 993                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_160K</constant>&nbsp;</entry>
 994                       <entry>160 kbit/s</entry>
 995                     </row>
 996                     <row>
 997                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_192K</constant>&nbsp;</entry>
 998                       <entry>192 kbit/s</entry>
 999                     </row>
1000                     <row>
1001                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_224K</constant>&nbsp;</entry>
1002                       <entry>224 kbit/s</entry>
1003                     </row>
1004                     <row>
1005                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_256K</constant>&nbsp;</entry>
1006                       <entry>256 kbit/s</entry>
1007                     </row>
1008                     <row>
1009                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_288K</constant>&nbsp;</entry>
1010                       <entry>288 kbit/s</entry>
1011                     </row>
1012                     <row>
1013                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_320K</constant>&nbsp;</entry>
1014                       <entry>320 kbit/s</entry>
1015                     </row>
1016                     <row>
1017                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_352K</constant>&nbsp;</entry>
1018                       <entry>352 kbit/s</entry>
1019                     </row>
1020                     <row>
1021                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_384K</constant>&nbsp;</entry>
1022                       <entry>384 kbit/s</entry>
1023                     </row>
1024                     <row>
1025                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_416K</constant>&nbsp;</entry>
1026                       <entry>416 kbit/s</entry>
1027                     </row>
1028                     <row>
1029                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_448K</constant>&nbsp;</entry>
1030                       <entry>448 kbit/s</entry>
1031                     </row>
1032                   </tbody>
1033                 </entrytbl>
1034               </row>
1035               <row><entry></entry></row>
1036               <row id="v4l2-mpeg-audio-l2-bitrate">
1037                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L2_BITRATE</constant>&nbsp;</entry>
1038                 <entry>enum&nbsp;v4l2_mpeg_audio_l2_bitrate</entry>
1039               </row><row><entry spanname="descr">MPEG-1/2 Layer II bitrate.
1040 Possible values are:</entry>
1041               </row>
1042               <row>
1043                 <entrytbl spanname="descr" cols="2">
1044                   <tbody valign="top">
1045                     <row>
1046                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_32K</constant>&nbsp;</entry>
1047                       <entry>32 kbit/s</entry>
1048                     </row>
1049                     <row>
1050                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_48K</constant>&nbsp;</entry>
1051                       <entry>48 kbit/s</entry>
1052                     </row>
1053                     <row>
1054                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_56K</constant>&nbsp;</entry>
1055                       <entry>56 kbit/s</entry>
1056                     </row>
1057                     <row>
1058                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_64K</constant>&nbsp;</entry>
1059                       <entry>64 kbit/s</entry>
1060                     </row>
1061                     <row>
1062                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_80K</constant>&nbsp;</entry>
1063                       <entry>80 kbit/s</entry>
1064                     </row>
1065                     <row>
1066                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_96K</constant>&nbsp;</entry>
1067                       <entry>96 kbit/s</entry>
1068                     </row>
1069                     <row>
1070                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_112K</constant>&nbsp;</entry>
1071                       <entry>112 kbit/s</entry>
1072                     </row>
1073                     <row>
1074                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_128K</constant>&nbsp;</entry>
1075                       <entry>128 kbit/s</entry>
1076                     </row>
1077                     <row>
1078                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_160K</constant>&nbsp;</entry>
1079                       <entry>160 kbit/s</entry>
1080                     </row>
1081                     <row>
1082                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_192K</constant>&nbsp;</entry>
1083                       <entry>192 kbit/s</entry>
1084                     </row>
1085                     <row>
1086                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_224K</constant>&nbsp;</entry>
1087                       <entry>224 kbit/s</entry>
1088                     </row>
1089                     <row>
1090                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_256K</constant>&nbsp;</entry>
1091                       <entry>256 kbit/s</entry>
1092                     </row>
1093                     <row>
1094                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_320K</constant>&nbsp;</entry>
1095                       <entry>320 kbit/s</entry>
1096                     </row>
1097                     <row>
1098                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_384K</constant>&nbsp;</entry>
1099                       <entry>384 kbit/s</entry>
1100                     </row>
1101                   </tbody>
1102                 </entrytbl>
1103               </row>
1104               <row><entry></entry></row>
1105               <row id="v4l2-mpeg-audio-l3-bitrate">
1106                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L3_BITRATE</constant>&nbsp;</entry>
1107                 <entry>enum&nbsp;v4l2_mpeg_audio_l3_bitrate</entry>
1108               </row><row><entry spanname="descr">MPEG-1/2 Layer III bitrate.
1109 Possible values are:</entry>
1110               </row>
1111               <row>
1112                 <entrytbl spanname="descr" cols="2">
1113                   <tbody valign="top">
1114                     <row>
1115                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_32K</constant>&nbsp;</entry>
1116                       <entry>32 kbit/s</entry>
1117                     </row>
1118                     <row>
1119                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_40K</constant>&nbsp;</entry>
1120                       <entry>40 kbit/s</entry>
1121                     </row>
1122                     <row>
1123                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_48K</constant>&nbsp;</entry>
1124                       <entry>48 kbit/s</entry>
1125                     </row>
1126                     <row>
1127                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_56K</constant>&nbsp;</entry>
1128                       <entry>56 kbit/s</entry>
1129                     </row>
1130                     <row>
1131                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_64K</constant>&nbsp;</entry>
1132                       <entry>64 kbit/s</entry>
1133                     </row>
1134                     <row>
1135                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_80K</constant>&nbsp;</entry>
1136                       <entry>80 kbit/s</entry>
1137                     </row>
1138                     <row>
1139                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_96K</constant>&nbsp;</entry>
1140                       <entry>96 kbit/s</entry>
1141                     </row>
1142                     <row>
1143                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_112K</constant>&nbsp;</entry>
1144                       <entry>112 kbit/s</entry>
1145                     </row>
1146                     <row>
1147                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_128K</constant>&nbsp;</entry>
1148                       <entry>128 kbit/s</entry>
1149                     </row>
1150                     <row>
1151                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_160K</constant>&nbsp;</entry>
1152                       <entry>160 kbit/s</entry>
1153                     </row>
1154                     <row>
1155                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_192K</constant>&nbsp;</entry>
1156                       <entry>192 kbit/s</entry>
1157                     </row>
1158                     <row>
1159                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_224K</constant>&nbsp;</entry>
1160                       <entry>224 kbit/s</entry>
1161                     </row>
1162                     <row>
1163                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_256K</constant>&nbsp;</entry>
1164                       <entry>256 kbit/s</entry>
1165                     </row>
1166                     <row>
1167                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_320K</constant>&nbsp;</entry>
1168                       <entry>320 kbit/s</entry>
1169                     </row>
1170                   </tbody>
1171                 </entrytbl>
1172               </row>
1173               <row><entry></entry></row>
1174               <row>
1175                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AAC_BITRATE</constant>&nbsp;</entry>
1176                 <entry>integer</entry>
1177               </row><row><entry spanname="descr">AAC bitrate in bits per second.</entry>
1178               </row>
1179               <row><entry></entry></row>
1180               <row id="v4l2-mpeg-audio-ac3-bitrate">
1181                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AC3_BITRATE</constant>&nbsp;</entry>
1182                 <entry>enum&nbsp;v4l2_mpeg_audio_ac3_bitrate</entry>
1183               </row><row><entry spanname="descr">AC-3 bitrate.
1184 Possible values are:</entry>
1185               </row>
1186               <row>
1187                 <entrytbl spanname="descr" cols="2">
1188                   <tbody valign="top">
1189                     <row>
1190                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_32K</constant>&nbsp;</entry>
1191                       <entry>32 kbit/s</entry>
1192                     </row>
1193                     <row>
1194                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_40K</constant>&nbsp;</entry>
1195                       <entry>40 kbit/s</entry>
1196                     </row>
1197                     <row>
1198                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_48K</constant>&nbsp;</entry>
1199                       <entry>48 kbit/s</entry>
1200                     </row>
1201                     <row>
1202                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_56K</constant>&nbsp;</entry>
1203                       <entry>56 kbit/s</entry>
1204                     </row>
1205                     <row>
1206                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_64K</constant>&nbsp;</entry>
1207                       <entry>64 kbit/s</entry>
1208                     </row>
1209                     <row>
1210                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_80K</constant>&nbsp;</entry>
1211                       <entry>80 kbit/s</entry>
1212                     </row>
1213                     <row>
1214                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_96K</constant>&nbsp;</entry>
1215                       <entry>96 kbit/s</entry>
1216                     </row>
1217                     <row>
1218                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_112K</constant>&nbsp;</entry>
1219                       <entry>112 kbit/s</entry>
1220                     </row>
1221                     <row>
1222                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_128K</constant>&nbsp;</entry>
1223                       <entry>128 kbit/s</entry>
1224                     </row>
1225                     <row>
1226                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_160K</constant>&nbsp;</entry>
1227                       <entry>160 kbit/s</entry>
1228                     </row>
1229                     <row>
1230                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_192K</constant>&nbsp;</entry>
1231                       <entry>192 kbit/s</entry>
1232                     </row>
1233                     <row>
1234                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_224K</constant>&nbsp;</entry>
1235                       <entry>224 kbit/s</entry>
1236                     </row>
1237                     <row>
1238                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_256K</constant>&nbsp;</entry>
1239                       <entry>256 kbit/s</entry>
1240                     </row>
1241                     <row>
1242                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_320K</constant>&nbsp;</entry>
1243                       <entry>320 kbit/s</entry>
1244                     </row>
1245                     <row>
1246                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_384K</constant>&nbsp;</entry>
1247                       <entry>384 kbit/s</entry>
1248                     </row>
1249                     <row>
1250                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_448K</constant>&nbsp;</entry>
1251                       <entry>448 kbit/s</entry>
1252                     </row>
1253                     <row>
1254                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_512K</constant>&nbsp;</entry>
1255                       <entry>512 kbit/s</entry>
1256                     </row>
1257                     <row>
1258                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_576K</constant>&nbsp;</entry>
1259                       <entry>576 kbit/s</entry>
1260                     </row>
1261                     <row>
1262                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_640K</constant>&nbsp;</entry>
1263                       <entry>640 kbit/s</entry>
1264                     </row>
1265                   </tbody>
1266                 </entrytbl>
1267               </row>
1268               <row><entry></entry></row>
1269               <row id="v4l2-mpeg-audio-mode">
1270                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE</constant>&nbsp;</entry>
1271                 <entry>enum&nbsp;v4l2_mpeg_audio_mode</entry>
1272               </row><row><entry spanname="descr">MPEG Audio mode.
1273 Possible values are:</entry>
1274               </row>
1275               <row>
1276                 <entrytbl spanname="descr" cols="2">
1277                   <tbody valign="top">
1278                     <row>
1279                       <entry><constant>V4L2_MPEG_AUDIO_MODE_STEREO</constant>&nbsp;</entry>
1280                       <entry>Stereo</entry>
1281                     </row>
1282                     <row>
1283                       <entry><constant>V4L2_MPEG_AUDIO_MODE_JOINT_STEREO</constant>&nbsp;</entry>
1284                       <entry>Joint Stereo</entry>
1285                     </row>
1286                     <row>
1287                       <entry><constant>V4L2_MPEG_AUDIO_MODE_DUAL</constant>&nbsp;</entry>
1288                       <entry>Bilingual</entry>
1289                     </row>
1290                     <row>
1291                       <entry><constant>V4L2_MPEG_AUDIO_MODE_MONO</constant>&nbsp;</entry>
1292                       <entry>Mono</entry>
1293                     </row>
1294                   </tbody>
1295                 </entrytbl>
1296               </row>
1297               <row><entry></entry></row>
1298               <row id="v4l2-mpeg-audio-mode-extension">
1299                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE_EXTENSION</constant>&nbsp;</entry>
1300                 <entry>enum&nbsp;v4l2_mpeg_audio_mode_extension</entry>
1301               </row><row><entry spanname="descr">Joint Stereo
1302 audio mode extension. In Layer I and II they indicate which subbands
1303 are in intensity stereo. All other subbands are coded in stereo. Layer
1304 III is not (yet) supported. Possible values
1305 are:</entry>
1306               </row>
1307               <row>
1308                 <entrytbl spanname="descr" cols="2">
1309                   <tbody valign="top">
1310                     <row>
1311                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4</constant>&nbsp;</entry>
1312                       <entry>Subbands 4-31 in intensity stereo</entry>
1313                     </row>
1314                     <row>
1315                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_8</constant>&nbsp;</entry>
1316                       <entry>Subbands 8-31 in intensity stereo</entry>
1317                     </row>
1318                     <row>
1319                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_12</constant>&nbsp;</entry>
1320                       <entry>Subbands 12-31 in intensity stereo</entry>
1321                     </row>
1322                     <row>
1323                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16</constant>&nbsp;</entry>
1324                       <entry>Subbands 16-31 in intensity stereo</entry>
1325                     </row>
1326                   </tbody>
1327                 </entrytbl>
1328               </row>
1329               <row><entry></entry></row>
1330               <row id="v4l2-mpeg-audio-emphasis">
1331                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_EMPHASIS</constant>&nbsp;</entry>
1332                 <entry>enum&nbsp;v4l2_mpeg_audio_emphasis</entry>
1333               </row><row><entry spanname="descr">Audio Emphasis.
1334 Possible values are:</entry>
1335               </row>
1336               <row>
1337                 <entrytbl spanname="descr" cols="2">
1338                   <tbody valign="top">
1339                     <row>
1340                       <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_NONE</constant>&nbsp;</entry>
1341                       <entry>None</entry>
1342                     </row>
1343                     <row>
1344                       <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_50_DIV_15_uS</constant>&nbsp;</entry>
1345                       <entry>50/15 microsecond emphasis</entry>
1346                     </row>
1347                     <row>
1348                       <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17</constant>&nbsp;</entry>
1349                       <entry>CCITT J.17</entry>
1350                     </row>
1351                   </tbody>
1352                 </entrytbl>
1353               </row>
1354               <row><entry></entry></row>
1355               <row id="v4l2-mpeg-audio-crc">
1356                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_CRC</constant>&nbsp;</entry>
1357                 <entry>enum&nbsp;v4l2_mpeg_audio_crc</entry>
1358               </row><row><entry spanname="descr">CRC method. Possible
1359 values are:</entry>
1360               </row>
1361               <row>
1362                 <entrytbl spanname="descr" cols="2">
1363                   <tbody valign="top">
1364                     <row>
1365                       <entry><constant>V4L2_MPEG_AUDIO_CRC_NONE</constant>&nbsp;</entry>
1366                       <entry>None</entry>
1367                     </row>
1368                     <row>
1369                       <entry><constant>V4L2_MPEG_AUDIO_CRC_CRC16</constant>&nbsp;</entry>
1370                       <entry>16 bit parity check</entry>
1371                     </row>
1372                   </tbody>
1373                 </entrytbl>
1374               </row>
1375               <row><entry></entry></row>
1376               <row>
1377                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MUTE</constant>&nbsp;</entry>
1378                 <entry>boolean</entry>
1379               </row><row><entry spanname="descr">Mutes the audio when
1380 capturing. This is not done by muting audio hardware, which can still
1381 produce a slight hiss, but in the encoder itself, guaranteeing a fixed
1382 and reproducible audio bitstream. 0 = unmuted, 1 = muted.</entry>
1383               </row>
1384               <row><entry></entry></row>
1385               <row id="v4l2-mpeg-audio-dec-playback">
1386                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK</constant>&nbsp;</entry>
1387                 <entry>enum&nbsp;v4l2_mpeg_audio_dec_playback</entry>
1388               </row><row><entry spanname="descr">Determines how monolingual audio should be played back.
1389 Possible values are:</entry>
1390               </row>
1391               <row>
1392                 <entrytbl spanname="descr" cols="2">
1393                   <tbody valign="top">
1394                     <row>
1395                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_AUTO</constant>&nbsp;</entry>
1396                       <entry>Automatically determines the best playback mode.</entry>
1397                     </row>
1398                     <row>
1399                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_STEREO</constant>&nbsp;</entry>
1400                       <entry>Stereo playback.</entry>
1401                     </row>
1402                     <row>
1403                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_LEFT</constant>&nbsp;</entry>
1404                       <entry>Left channel playback.</entry>
1405                     </row>
1406                     <row>
1407                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_RIGHT</constant>&nbsp;</entry>
1408                       <entry>Right channel playback.</entry>
1409                     </row>
1410                     <row>
1411                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_MONO</constant>&nbsp;</entry>
1412                       <entry>Mono playback.</entry>
1413                     </row>
1414                     <row>
1415                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_SWAPPED_STEREO</constant>&nbsp;</entry>
1416                       <entry>Stereo playback with swapped left and right channels.</entry>
1417                     </row>
1418                   </tbody>
1419                 </entrytbl>
1420               </row>
1421               <row><entry></entry></row>
1422               <row id="v4l2-mpeg-audio-dec-multilingual-playback">
1423                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK</constant>&nbsp;</entry>
1424                 <entry>enum&nbsp;v4l2_mpeg_audio_dec_playback</entry>
1425               </row><row><entry spanname="descr">Determines how multilingual audio should be played back.</entry>
1426               </row>
1427               <row><entry></entry></row>
1428               <row id="v4l2-mpeg-video-encoding">
1429                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ENCODING</constant>&nbsp;</entry>
1430                 <entry>enum&nbsp;v4l2_mpeg_video_encoding</entry>
1431               </row><row><entry spanname="descr">MPEG Video encoding
1432 method. This control is specific to multiplexed MPEG streams.
1433 Possible values are:</entry>
1434               </row>
1435               <row>
1436                 <entrytbl spanname="descr" cols="2">
1437                   <tbody valign="top">
1438                     <row>
1439                       <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_1</constant>&nbsp;</entry>
1440                       <entry>MPEG-1 Video encoding</entry>
1441                     </row>
1442                     <row>
1443                       <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_2</constant>&nbsp;</entry>
1444                       <entry>MPEG-2 Video encoding</entry>
1445                     </row>
1446                     <row>
1447                       <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC</constant>&nbsp;</entry>
1448                       <entry>MPEG-4 AVC (H.264) Video encoding</entry>
1449                     </row>
1450                   </tbody>
1451                 </entrytbl>
1452               </row>
1453               <row><entry></entry></row>
1454               <row id="v4l2-mpeg-video-aspect">
1455                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ASPECT</constant>&nbsp;</entry>
1456                 <entry>enum&nbsp;v4l2_mpeg_video_aspect</entry>
1457               </row><row><entry spanname="descr">Video aspect.
1458 Possible values are:</entry>
1459               </row>
1460               <row>
1461                 <entrytbl spanname="descr" cols="2">
1462                   <tbody valign="top">
1463                     <row>
1464                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_1x1</constant>&nbsp;</entry>
1465                     </row>
1466                     <row>
1467                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_4x3</constant>&nbsp;</entry>
1468                     </row>
1469                     <row>
1470                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_16x9</constant>&nbsp;</entry>
1471                     </row>
1472                     <row>
1473                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_221x100</constant>&nbsp;</entry>
1474                     </row>
1475                   </tbody>
1476                 </entrytbl>
1477               </row>
1478               <row><entry></entry></row>
1479               <row>
1480                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_B_FRAMES</constant>&nbsp;</entry>
1481                 <entry>integer</entry>
1482               </row><row><entry spanname="descr">Number of B-Frames
1483 (default 2)</entry>
1484               </row>
1485               <row><entry></entry></row>
1486               <row>
1487                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_SIZE</constant>&nbsp;</entry>
1488                 <entry>integer</entry>
1489               </row><row><entry spanname="descr">GOP size (default
1490 12)</entry>
1491               </row>
1492               <row><entry></entry></row>
1493               <row>
1494                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_CLOSURE</constant>&nbsp;</entry>
1495                 <entry>boolean</entry>
1496               </row><row><entry spanname="descr">GOP closure (default
1497 1)</entry>
1498               </row>
1499               <row><entry></entry></row>
1500               <row>
1501                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_PULLDOWN</constant>&nbsp;</entry>
1502                 <entry>boolean</entry>
1503               </row><row><entry spanname="descr">Enable 3:2 pulldown
1504 (default 0)</entry>
1505               </row>
1506               <row><entry></entry></row>
1507               <row id="v4l2-mpeg-video-bitrate-mode">
1508                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_MODE</constant>&nbsp;</entry>
1509                 <entry>enum&nbsp;v4l2_mpeg_video_bitrate_mode</entry>
1510               </row><row><entry spanname="descr">Video bitrate mode.
1511 Possible values are:</entry>
1512               </row>
1513               <row>
1514                 <entrytbl spanname="descr" cols="2">
1515                   <tbody valign="top">
1516                     <row>
1517                       <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_VBR</constant>&nbsp;</entry>
1518                       <entry>Variable bitrate</entry>
1519                     </row>
1520                     <row>
1521                       <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_CBR</constant>&nbsp;</entry>
1522                       <entry>Constant bitrate</entry>
1523                     </row>
1524                   </tbody>
1525                 </entrytbl>
1526               </row>
1527               <row><entry></entry></row>
1528               <row>
1529                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE</constant>&nbsp;</entry>
1530                 <entry>integer</entry>
1531               </row><row><entry spanname="descr">Video bitrate in bits
1532 per second.</entry>
1533               </row>
1534               <row><entry></entry></row>
1535               <row>
1536                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_PEAK</constant>&nbsp;</entry>
1537                 <entry>integer</entry>
1538               </row><row><entry spanname="descr">Peak video bitrate in
1539 bits per second. Must be larger or equal to the average video bitrate.
1540 It is ignored if the video bitrate mode is set to constant
1541 bitrate.</entry>
1542               </row>
1543               <row><entry></entry></row>
1544               <row>
1545                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION</constant>&nbsp;</entry>
1546                 <entry>integer</entry>
1547               </row><row><entry spanname="descr">For every captured
1548 frame, skip this many subsequent frames (default 0).</entry>
1549               </row>
1550               <row><entry></entry></row>
1551               <row>
1552                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE</constant>&nbsp;</entry>
1553                 <entry>boolean</entry>
1554               </row>
1555               <row><entry spanname="descr">"Mutes" the video to a
1556 fixed color when capturing. This is useful for testing, to produce a
1557 fixed video bitstream. 0 = unmuted, 1 = muted.</entry>
1558               </row>
1559               <row><entry></entry></row>
1560               <row>
1561                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE_YUV</constant>&nbsp;</entry>
1562                 <entry>integer</entry>
1563               </row><row><entry spanname="descr">Sets the "mute" color
1564 of the video. The supplied 32-bit integer is interpreted as follows (bit
1565 0 = least significant bit):</entry>
1566               </row>
1567               <row>
1568                 <entrytbl spanname="descr" cols="2">
1569                   <tbody valign="top">
1570                     <row>
1571                       <entry>Bit 0:7</entry>
1572                       <entry>V chrominance information</entry>
1573                     </row>
1574                     <row>
1575                       <entry>Bit 8:15</entry>
1576                       <entry>U chrominance information</entry>
1577                     </row>
1578                     <row>
1579                       <entry>Bit 16:23</entry>
1580                       <entry>Y luminance information</entry>
1581                     </row>
1582                     <row>
1583                       <entry>Bit 24:31</entry>
1584                       <entry>Must be zero.</entry>
1585                     </row>
1586                   </tbody>
1587                 </entrytbl>
1588               </row>
1589               <row><entry></entry></row>
1590               <row id="v4l2-mpeg-video-dec-pts">
1591                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_PTS</constant>&nbsp;</entry>
1592                 <entry>integer64</entry>
1593               </row><row><entry spanname="descr">This read-only control returns the
1594 33-bit video Presentation Time Stamp as defined in ITU T-REC-H.222.0 and ISO/IEC 13818-1 of
1595 the currently displayed frame. This is the same PTS as is used in &VIDIOC-DECODER-CMD;.</entry>
1596               </row>
1597               <row><entry></entry></row>
1598               <row id="v4l2-mpeg-video-dec-frame">
1599                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_FRAME</constant>&nbsp;</entry>
1600                 <entry>integer64</entry>
1601               </row><row><entry spanname="descr">This read-only control returns the
1602 frame counter of the frame that is currently displayed (decoded). This value is reset to 0 whenever
1603 the decoder is started.</entry>
1604               </row>
1605
1606               <row><entry></entry></row>
1607               <row>
1608                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE</constant>&nbsp;</entry>
1609                 <entry>boolean</entry>
1610               </row>
1611               <row><entry spanname="descr">If enabled the decoder expects to receive a single slice per buffer, otherwise
1612 the decoder expects a single frame in per buffer. Applicable to the decoder, all codecs.
1613 </entry>
1614               </row>
1615
1616               <row><entry></entry></row>
1617               <row>
1618                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE</constant>&nbsp;</entry>
1619                 <entry>boolean</entry>
1620               </row>
1621               <row><entry spanname="descr">Enable writing sample aspect ratio in the Video Usability Information.
1622 Applicable to the H264 encoder.</entry>
1623               </row>
1624
1625               <row><entry></entry></row>
1626               <row id="v4l2-mpeg-video-h264-vui-sar-idc">
1627                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC</constant>&nbsp;</entry>
1628                 <entry>enum&nbsp;v4l2_mpeg_video_h264_vui_sar_idc</entry>
1629               </row>
1630               <row><entry spanname="descr">VUI sample aspect ratio indicator for H.264 encoding. The value
1631 is defined in the table E-1 in the standard. Applicable to the H264 encoder.</entry>
1632               </row>
1633               <row>
1634                 <entrytbl spanname="descr" cols="2">
1635                   <tbody valign="top">
1636
1637                         <row>
1638                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_UNSPECIFIED</constant>&nbsp;</entry>
1639                           <entry>Unspecified</entry>
1640                         </row>
1641                         <row>
1642                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_1x1</constant>&nbsp;</entry>
1643                           <entry>1x1</entry>
1644                         </row>
1645                         <row>
1646                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_12x11</constant>&nbsp;</entry>
1647                           <entry>12x11</entry>
1648                         </row>
1649                         <row>
1650                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_10x11</constant>&nbsp;</entry>
1651                           <entry>10x11</entry>
1652                         </row>
1653                         <row>
1654                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_16x11</constant>&nbsp;</entry>
1655                           <entry>16x11</entry>
1656                         </row>
1657                         <row>
1658                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_40x33</constant>&nbsp;</entry>
1659                           <entry>40x33</entry>
1660                         </row>
1661                         <row>
1662                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_24x11</constant>&nbsp;</entry>
1663                           <entry>24x11</entry>
1664                         </row>
1665                         <row>
1666                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_20x11</constant>&nbsp;</entry>
1667                           <entry>20x11</entry>
1668                         </row>
1669                         <row>
1670                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_32x11</constant>&nbsp;</entry>
1671                           <entry>32x11</entry>
1672                         </row>
1673                         <row>
1674                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_80x33</constant>&nbsp;</entry>
1675                           <entry>80x33</entry>
1676                         </row>
1677                         <row>
1678                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_18x11</constant>&nbsp;</entry>
1679                           <entry>18x11</entry>
1680                         </row>
1681                         <row>
1682                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_15x11</constant>&nbsp;</entry>
1683                           <entry>15x11</entry>
1684                         </row>
1685                         <row>
1686                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_64x33</constant>&nbsp;</entry>
1687                           <entry>64x33</entry>
1688                         </row>
1689                         <row>
1690                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_160x99</constant>&nbsp;</entry>
1691                           <entry>160x99</entry>
1692                         </row>
1693                         <row>
1694                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_4x3</constant>&nbsp;</entry>
1695                           <entry>4x3</entry>
1696                         </row>
1697                         <row>
1698                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_3x2</constant>&nbsp;</entry>
1699                           <entry>3x2</entry>
1700                         </row>
1701                         <row>
1702                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_2x1</constant>&nbsp;</entry>
1703                           <entry>2x1</entry>
1704                         </row>
1705                         <row>
1706                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_EXTENDED</constant>&nbsp;</entry>
1707                           <entry>Extended SAR</entry>
1708                         </row>
1709                   </tbody>
1710                 </entrytbl>
1711               </row>
1712
1713               <row><entry></entry></row>
1714               <row>
1715                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH</constant>&nbsp;</entry>
1716                 <entry>integer</entry>
1717               </row>
1718               <row><entry spanname="descr">Extended sample aspect ratio width for H.264 VUI encoding.
1719 Applicable to the H264 encoder.</entry>
1720               </row>
1721
1722               <row><entry></entry></row>
1723               <row>
1724                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT</constant>&nbsp;</entry>
1725                 <entry>integer</entry>
1726               </row>
1727               <row><entry spanname="descr">Extended sample aspect ratio height for H.264 VUI encoding.
1728 Applicable to the H264 encoder.</entry>
1729               </row>
1730
1731               <row><entry></entry></row>
1732               <row id="v4l2-mpeg-video-h264-level">
1733                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LEVEL</constant>&nbsp;</entry>
1734                 <entry>enum&nbsp;v4l2_mpeg_video_h264_level</entry>
1735               </row>
1736               <row><entry spanname="descr">The level information for the H264 video elementary stream.
1737 Applicable to the H264 encoder.
1738 Possible values are:</entry>
1739               </row>
1740               <row>
1741                 <entrytbl spanname="descr" cols="2">
1742                   <tbody valign="top">
1743                     <row>
1744                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_0</constant>&nbsp;</entry>
1745                       <entry>Level 1.0</entry>
1746                     </row>
1747                     <row>
1748                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1B</constant>&nbsp;</entry>
1749                       <entry>Level 1B</entry>
1750                     </row>
1751                     <row>
1752                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_1</constant>&nbsp;</entry>
1753                       <entry>Level 1.1</entry>
1754                     </row>
1755                     <row>
1756                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_2</constant>&nbsp;</entry>
1757                       <entry>Level 1.2</entry>
1758                     </row>
1759                     <row>
1760                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_3</constant>&nbsp;</entry>
1761                       <entry>Level 1.3</entry>
1762                     </row>
1763                     <row>
1764                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_0</constant>&nbsp;</entry>
1765                       <entry>Level 2.0</entry>
1766                     </row>
1767                     <row>
1768                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_1</constant>&nbsp;</entry>
1769                       <entry>Level 2.1</entry>
1770                     </row>
1771                     <row>
1772                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_2</constant>&nbsp;</entry>
1773                       <entry>Level 2.2</entry>
1774                     </row>
1775                     <row>
1776                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_0</constant>&nbsp;</entry>
1777                       <entry>Level 3.0</entry>
1778                     </row>
1779                     <row>
1780                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_1</constant>&nbsp;</entry>
1781                       <entry>Level 3.1</entry>
1782                     </row>
1783                     <row>
1784                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_2</constant>&nbsp;</entry>
1785                       <entry>Level 3.2</entry>
1786                     </row>
1787                     <row>
1788                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_0</constant>&nbsp;</entry>
1789                       <entry>Level 4.0</entry>
1790                     </row>
1791                     <row>
1792                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_1</constant>&nbsp;</entry>
1793                       <entry>Level 4.1</entry>
1794                     </row>
1795                     <row>
1796                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_2</constant>&nbsp;</entry>
1797                       <entry>Level 4.2</entry>
1798                     </row>
1799                     <row>
1800                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_0</constant>&nbsp;</entry>
1801                       <entry>Level 5.0</entry>
1802                     </row>
1803                     <row>
1804                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_1</constant>&nbsp;</entry>
1805                       <entry>Level 5.1</entry>
1806                     </row>
1807                   </tbody>
1808                 </entrytbl>
1809               </row>
1810
1811               <row><entry></entry></row>
1812               <row id="v4l2-mpeg-video-mpeg4-level">
1813                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL</constant>&nbsp;</entry>
1814                 <entry>enum&nbsp;v4l2_mpeg_video_mpeg4_level</entry>
1815               </row>
1816               <row><entry spanname="descr">The level information for the MPEG4 elementary stream.
1817 Applicable to the MPEG4 encoder.
1818 Possible values are:</entry>
1819               </row>
1820               <row>
1821                 <entrytbl spanname="descr" cols="2">
1822                   <tbody valign="top">
1823                     <row>
1824                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0</constant>&nbsp;</entry>
1825                       <entry>Level 0</entry>
1826                     </row>
1827                     <row>
1828                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0B</constant>&nbsp;</entry>
1829                       <entry>Level 0b</entry>
1830                     </row>
1831                     <row>
1832                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_1</constant>&nbsp;</entry>
1833                       <entry>Level 1</entry>
1834                     </row>
1835                     <row>
1836                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_2</constant>&nbsp;</entry>
1837                       <entry>Level 2</entry>
1838                     </row>
1839                     <row>
1840                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3</constant>&nbsp;</entry>
1841                       <entry>Level 3</entry>
1842                     </row>
1843                     <row>
1844                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3B</constant>&nbsp;</entry>
1845                       <entry>Level 3b</entry>
1846                     </row>
1847                     <row>
1848                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_4</constant>&nbsp;</entry>
1849                       <entry>Level 4</entry>
1850                     </row>
1851                     <row>
1852                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_5</constant>&nbsp;</entry>
1853                       <entry>Level 5</entry>
1854                     </row>
1855                   </tbody>
1856                 </entrytbl>
1857               </row>
1858
1859               <row><entry></entry></row>
1860               <row id="v4l2-mpeg-video-h264-profile">
1861                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_PROFILE</constant>&nbsp;</entry>
1862                 <entry>enum&nbsp;v4l2_mpeg_video_h264_profile</entry>
1863               </row>
1864               <row><entry spanname="descr">The profile information for H264.
1865 Applicable to the H264 encoder.
1866 Possible values are:</entry>
1867               </row>
1868               <row>
1869                 <entrytbl spanname="descr" cols="2">
1870                   <tbody valign="top">
1871                     <row>
1872                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE</constant>&nbsp;</entry>
1873                       <entry>Baseline profile</entry>
1874                     </row>
1875                     <row>
1876                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE</constant>&nbsp;</entry>
1877                       <entry>Constrained Baseline profile</entry>
1878                     </row>
1879                     <row>
1880                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MAIN</constant>&nbsp;</entry>
1881                       <entry>Main profile</entry>
1882                     </row>
1883                     <row>
1884                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED</constant>&nbsp;</entry>
1885                       <entry>Extended profile</entry>
1886                     </row>
1887                     <row>
1888                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH</constant>&nbsp;</entry>
1889                       <entry>High profile</entry>
1890                     </row>
1891                     <row>
1892                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10</constant>&nbsp;</entry>
1893                       <entry>High 10 profile</entry>
1894                     </row>
1895                     <row>
1896                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422</constant>&nbsp;</entry>
1897                       <entry>High 422 profile</entry>
1898                     </row>
1899                     <row>
1900                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE</constant>&nbsp;</entry>
1901                       <entry>High 444 Predictive profile</entry>
1902                     </row>
1903                     <row>
1904                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10_INTRA</constant>&nbsp;</entry>
1905                       <entry>High 10 Intra profile</entry>
1906                     </row>
1907                     <row>
1908                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422_INTRA</constant>&nbsp;</entry>
1909                       <entry>High 422 Intra profile</entry>
1910                     </row>
1911                     <row>
1912                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_INTRA</constant>&nbsp;</entry>
1913                       <entry>High 444 Intra profile</entry>
1914                     </row>
1915                     <row>
1916                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CAVLC_444_INTRA</constant>&nbsp;</entry>
1917                       <entry>CAVLC 444 Intra profile</entry>
1918                     </row>
1919                     <row>
1920                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE</constant>&nbsp;</entry>
1921                       <entry>Scalable Baseline profile</entry>
1922                     </row>
1923                     <row>
1924                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH</constant>&nbsp;</entry>
1925                       <entry>Scalable High profile</entry>
1926                     </row>
1927                     <row>
1928                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH_INTRA</constant>&nbsp;</entry>
1929                       <entry>Scalable High Intra profile</entry>
1930                     </row>
1931                     <row>
1932                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH</constant>&nbsp;</entry>
1933                       <entry>Stereo High profile</entry>
1934                     </row>
1935                     <row>
1936                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH</constant>&nbsp;</entry>
1937                       <entry>Multiview High profile</entry>
1938                     </row>
1939
1940                   </tbody>
1941                 </entrytbl>
1942               </row>
1943
1944               <row><entry></entry></row>
1945               <row id="v4l2-mpeg-video-mpeg4-profile">
1946                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE</constant>&nbsp;</entry>
1947                 <entry>enum&nbsp;v4l2_mpeg_video_mpeg4_profile</entry>
1948               </row>
1949               <row><entry spanname="descr">The profile information for MPEG4.
1950 Applicable to the MPEG4 encoder.
1951 Possible values are:</entry>
1952               </row>
1953               <row>
1954                 <entrytbl spanname="descr" cols="2">
1955                   <tbody valign="top">
1956                     <row>
1957                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE</constant>&nbsp;</entry>
1958                       <entry>Simple profile</entry>
1959                     </row>
1960                     <row>
1961                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_SIMPLE</constant>&nbsp;</entry>
1962                       <entry>Advanced Simple profile</entry>
1963                     </row>
1964                     <row>
1965                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_CORE</constant>&nbsp;</entry>
1966                       <entry>Core profile</entry>
1967                     </row>
1968                     <row>
1969                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE_SCALABLE</constant>&nbsp;</entry>
1970                       <entry>Simple Scalable profile</entry>
1971                     </row>
1972                     <row>
1973                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_CODING_EFFICIENCY</constant>&nbsp;</entry>
1974                       <entry></entry>
1975                     </row>
1976                   </tbody>
1977                 </entrytbl>
1978               </row>
1979
1980               <row><entry></entry></row>
1981               <row>
1982                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MAX_REF_PIC</constant>&nbsp;</entry>
1983                 <entry>integer</entry>
1984               </row>
1985               <row><entry spanname="descr">The maximum number of reference pictures used for encoding.
1986 Applicable to the encoder.
1987 </entry>
1988               </row>
1989
1990               <row><entry></entry></row>
1991               <row id="v4l2-mpeg-video-multi-slice-mode">
1992                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant>&nbsp;</entry>
1993                 <entry>enum&nbsp;v4l2_mpeg_video_multi_slice_mode</entry>
1994               </row>
1995               <row><entry spanname="descr">Determines how the encoder should handle division of frame into slices.
1996 Applicable to the encoder.
1997 Possible values are:</entry>
1998               </row>
1999               <row>
2000                 <entrytbl spanname="descr" cols="2">
2001                   <tbody valign="top">
2002                     <row>
2003                       <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_SINGLE</constant>&nbsp;</entry>
2004                       <entry>Single slice per frame.</entry>
2005                     </row>
2006                     <row>
2007                       <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>&nbsp;</entry>
2008                       <entry>Multiple slices with set maximum number of macroblocks per slice.</entry>
2009                     </row>
2010                     <row>
2011                       <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>&nbsp;</entry>
2012                       <entry>Multiple slice with set maximum size in bytes per slice.</entry>
2013                     </row>
2014                   </tbody>
2015                 </entrytbl>
2016               </row>
2017
2018               <row><entry></entry></row>
2019               <row>
2020                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_MB</constant>&nbsp;</entry>
2021                 <entry>integer</entry>
2022               </row>
2023               <row><entry spanname="descr">The maximum number of macroblocks in a slice. Used when
2024 <constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>.
2025 Applicable to the encoder.</entry>
2026               </row>
2027
2028               <row><entry></entry></row>
2029               <row>
2030                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_BYTES</constant>&nbsp;</entry>
2031                 <entry>integer</entry>
2032               </row>
2033               <row><entry spanname="descr">The maximum size of a slice in bytes. Used when
2034 <constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>.
2035 Applicable to the encoder.</entry>
2036               </row>
2037
2038               <row><entry></entry></row>
2039               <row id="v4l2-mpeg-video-h264-loop-filter-mode">
2040                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_MODE</constant>&nbsp;</entry>
2041                 <entry>enum&nbsp;v4l2_mpeg_video_h264_loop_filter_mode</entry>
2042               </row>
2043               <row><entry spanname="descr">Loop filter mode for H264 encoder.
2044 Possible values are:</entry>
2045               </row>
2046               <row>
2047                 <entrytbl spanname="descr" cols="2">
2048                   <tbody valign="top">
2049                     <row>
2050                       <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_ENABLED</constant>&nbsp;</entry>
2051                       <entry>Loop filter is enabled.</entry>
2052                     </row>
2053                     <row>
2054                       <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED</constant>&nbsp;</entry>
2055                       <entry>Loop filter is disabled.</entry>
2056                     </row>
2057                     <row>
2058                       <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY</constant>&nbsp;</entry>
2059                       <entry>Loop filter is disabled at the slice boundary.</entry>
2060                     </row>
2061                   </tbody>
2062                 </entrytbl>
2063               </row>
2064
2065               <row><entry></entry></row>
2066               <row>
2067                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_ALPHA</constant>&nbsp;</entry>
2068                 <entry>integer</entry>
2069               </row>
2070               <row><entry spanname="descr">Loop filter alpha coefficient, defined in the H264 standard.
2071 Applicable to the H264 encoder.</entry>
2072               </row>
2073
2074               <row><entry></entry></row>
2075               <row>
2076                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_BETA</constant>&nbsp;</entry>
2077                 <entry>integer</entry>
2078               </row>
2079               <row><entry spanname="descr">Loop filter beta coefficient, defined in the H264 standard.
2080 Applicable to the H264 encoder.</entry>
2081               </row>
2082
2083               <row><entry></entry></row>
2084               <row id="v4l2-mpeg-video-h264-entropy-mode">
2085                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ENTROPY_MODE</constant>&nbsp;</entry>
2086                 <entry>enum&nbsp;v4l2_mpeg_video_h264_entropy_mode</entry>
2087               </row>
2088               <row><entry spanname="descr">Entropy coding mode for H264 - CABAC/CAVALC.
2089 Applicable to the H264 encoder.
2090 Possible values are:</entry>
2091               </row>
2092               <row>
2093                 <entrytbl spanname="descr" cols="2">
2094                   <tbody valign="top">
2095                     <row>
2096                       <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CAVLC</constant>&nbsp;</entry>
2097                       <entry>Use CAVLC entropy coding.</entry>
2098                     </row>
2099                     <row>
2100                       <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CABAC</constant>&nbsp;</entry>
2101                       <entry>Use CABAC entropy coding.</entry>
2102                     </row>
2103                   </tbody>
2104                 </entrytbl>
2105               </row>
2106
2107               <row><entry></entry></row>
2108               <row>
2109                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM</constant>&nbsp;</entry>
2110                 <entry>boolean</entry>
2111               </row>
2112               <row><entry spanname="descr">Enable 8X8 transform for H264. Applicable to the H264 encoder.</entry>
2113               </row>
2114
2115               <row><entry></entry></row>
2116               <row>
2117                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB</constant>&nbsp;</entry>
2118                 <entry>integer</entry>
2119               </row>
2120               <row><entry spanname="descr">Cyclic intra macroblock refresh. This is the number of continuous macroblocks
2121 refreshed every frame. Each frame a successive set of macroblocks is refreshed until the cycle completes and starts from the
2122 top of the frame. Applicable to H264, H263 and MPEG4 encoder.</entry>
2123               </row>
2124
2125               <row><entry></entry></row>
2126               <row>
2127                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE</constant>&nbsp;</entry>
2128                 <entry>boolean</entry>
2129               </row>
2130               <row><entry spanname="descr">Frame level rate control enable.
2131 If this control is disabled then the quantization parameter for each frame type is constant and set with appropriate controls
2132 (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>).
2133 If frame rate control is enabled then quantization parameter is adjusted to meet the chosen bitrate. Minimum and maximum value
2134 for the quantization parameter can be set with appropriate controls (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>).
2135 Applicable to encoders.</entry>
2136               </row>
2137
2138               <row><entry></entry></row>
2139               <row>
2140                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>&nbsp;</entry>
2141                 <entry>boolean</entry>
2142               </row>
2143               <row><entry spanname="descr">Macroblock level rate control enable.
2144 Applicable to the MPEG4 and H264 encoders.</entry>
2145               </row>
2146
2147               <row><entry></entry></row>
2148               <row>
2149                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_QPEL</constant>&nbsp;</entry>
2150                 <entry>boolean</entry>
2151               </row>
2152               <row><entry spanname="descr">Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4 encoder.</entry>
2153               </row>
2154
2155               <row><entry></entry></row>
2156               <row>
2157                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>&nbsp;</entry>
2158                 <entry>integer</entry>
2159               </row>
2160               <row><entry spanname="descr">Quantization parameter for an I frame for H263. Valid range: from 1 to 31.</entry>
2161               </row>
2162
2163               <row><entry></entry></row>
2164               <row>
2165                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>&nbsp;</entry>
2166                 <entry>integer</entry>
2167               </row>
2168               <row><entry spanname="descr">Minimum quantization parameter for H263. Valid range: from 1 to 31.</entry>
2169               </row>
2170
2171               <row><entry></entry></row>
2172               <row>
2173                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MAX_QP</constant>&nbsp;</entry>
2174                 <entry>integer</entry>
2175               </row>
2176               <row><entry spanname="descr">Maximum quantization parameter for H263. Valid range: from 1 to 31.</entry>
2177               </row>
2178
2179               <row><entry></entry></row>
2180               <row>
2181                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_P_FRAME_QP</constant>&nbsp;</entry>
2182                 <entry>integer</entry>
2183               </row>
2184               <row><entry spanname="descr">Quantization parameter for an P frame for H263. Valid range: from 1 to 31.</entry>
2185               </row>
2186
2187               <row><entry></entry></row>
2188               <row>
2189                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_B_FRAME_QP</constant>&nbsp;</entry>
2190                 <entry>integer</entry>
2191               </row>
2192               <row><entry spanname="descr">Quantization parameter for an B frame for H263. Valid range: from 1 to 31.</entry>
2193               </row>
2194
2195               <row><entry></entry></row>
2196               <row>
2197                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP</constant>&nbsp;</entry>
2198                 <entry>integer</entry>
2199               </row>
2200               <row><entry spanname="descr">Quantization parameter for an I frame for H264. Valid range: from 0 to 51.</entry>
2201               </row>
2202
2203               <row><entry></entry></row>
2204               <row>
2205                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MIN_QP</constant>&nbsp;</entry>
2206                 <entry>integer</entry>
2207               </row>
2208               <row><entry spanname="descr">Minimum quantization parameter for H264. Valid range: from 0 to 51.</entry>
2209               </row>
2210
2211               <row><entry></entry></row>
2212               <row>
2213                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MAX_QP</constant>&nbsp;</entry>
2214                 <entry>integer</entry>
2215               </row>
2216               <row><entry spanname="descr">Maximum quantization parameter for H264. Valid range: from 0 to 51.</entry>
2217               </row>
2218
2219               <row><entry></entry></row>
2220               <row>
2221                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_P_FRAME_QP</constant>&nbsp;</entry>
2222                 <entry>integer</entry>
2223               </row>
2224               <row><entry spanname="descr">Quantization parameter for an P frame for H264. Valid range: from 0 to 51.</entry>
2225               </row>
2226
2227               <row><entry></entry></row>
2228               <row>
2229                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_B_FRAME_QP</constant>&nbsp;</entry>
2230                 <entry>integer</entry>
2231               </row>
2232               <row><entry spanname="descr">Quantization parameter for an B frame for H264. Valid range: from 0 to 51.</entry>
2233               </row>
2234
2235               <row><entry></entry></row>
2236               <row>
2237                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP</constant>&nbsp;</entry>
2238                 <entry>integer</entry>
2239               </row>
2240               <row><entry spanname="descr">Quantization parameter for an I frame for MPEG4. Valid range: from 1 to 31.</entry>
2241               </row>
2242
2243               <row><entry></entry></row>
2244               <row>
2245                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MIN_QP</constant>&nbsp;</entry>
2246                 <entry>integer</entry>
2247               </row>
2248               <row><entry spanname="descr">Minimum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry>
2249               </row>
2250
2251               <row><entry></entry></row>
2252               <row>
2253                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MAX_QP</constant>&nbsp;</entry>
2254                 <entry>integer</entry>
2255               </row>
2256               <row><entry spanname="descr">Maximum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry>
2257               </row>
2258
2259               <row><entry></entry></row>
2260               <row>
2261                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP</constant>&nbsp;</entry>
2262                 <entry>integer</entry>
2263               </row>
2264               <row><entry spanname="descr">Quantization parameter for an P frame for MPEG4. Valid range: from 1 to 31.</entry>
2265               </row>
2266
2267               <row><entry></entry></row>
2268               <row>
2269                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP</constant>&nbsp;</entry>
2270                 <entry>integer</entry>
2271               </row>
2272               <row><entry spanname="descr">Quantization parameter for an B frame for MPEG4. Valid range: from 1 to 31.</entry>
2273               </row>
2274
2275               <row><entry></entry></row>
2276               <row>
2277                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_SIZE</constant>&nbsp;</entry>
2278                 <entry>integer</entry>
2279               </row>
2280               <row><entry spanname="descr">The Video Buffer Verifier size in kilobytes, it is used as a limitation of frame skip.
2281 The VBV is defined in the standard as a mean to verify that the produced stream will be successfully decoded.
2282 The standard describes it as "Part of a hypothetical decoder that is conceptually connected to the
2283 output of the encoder. Its purpose is to provide a constraint on the variability of the data rate that an
2284 encoder or editing process may produce.".
2285 Applicable to the MPEG1, MPEG2, MPEG4 encoders.</entry>
2286               </row>
2287
2288               <row><entry></entry></row>
2289               <row id="v4l2-mpeg-video-vbv-delay">
2290                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_DELAY</constant>&nbsp;</entry>
2291                 <entry>integer</entry>
2292               </row><row><entry spanname="descr">Sets the initial delay in milliseconds for
2293 VBV buffer control.</entry>
2294               </row>
2295
2296                   <row><entry></entry></row>
2297               <row id="v4l2-mpeg-video-hor-search-range">
2298                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MV_H_SEARCH_RANGE</constant>&nbsp;</entry>
2299                 <entry>integer</entry>
2300               </row>
2301                 <row><entry spanname="descr">Horizontal search range defines maximum horizontal search area in pixels
2302 to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set
2303 horizontal search range for motion estimation module in video encoder.</entry>
2304               </row>
2305
2306                  <row><entry></entry></row>
2307               <row id="v4l2-mpeg-video-vert-search-range">
2308                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE</constant>&nbsp;</entry>
2309                 <entry>integer</entry>
2310               </row>
2311                 <row><entry spanname="descr">Vertical search range defines maximum vertical search area in pixels
2312 to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set
2313 vertical search range for motion estimation module in video encoder.</entry>
2314               </row>
2315
2316               <row><entry></entry></row>
2317               <row>
2318                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE</constant>&nbsp;</entry>
2319                 <entry>integer</entry>
2320               </row>
2321               <row><entry spanname="descr">The Coded Picture Buffer size in kilobytes, it is used as a limitation of frame skip.
2322 The CPB is defined in the H264 standard as a mean to verify that the produced stream will be successfully decoded.
2323 Applicable to the H264 encoder.</entry>
2324               </row>
2325
2326               <row><entry></entry></row>
2327               <row>
2328                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_PERIOD</constant>&nbsp;</entry>
2329                 <entry>integer</entry>
2330               </row>
2331               <row><entry spanname="descr">Period between I-frames in the open GOP for H264. In case of an open GOP
2332 this is the period between two I-frames. The period between IDR (Instantaneous Decoding Refresh) frames is taken from the GOP_SIZE control.
2333 An IDR frame, which stands for Instantaneous Decoding Refresh is an I-frame after which no prior frames are
2334 referenced. This means that a stream can be restarted from an IDR frame without the need to store or decode any
2335 previous frames. Applicable to the H264 encoder.</entry>
2336               </row>
2337
2338               <row><entry></entry></row>
2339               <row id="v4l2-mpeg-video-header-mode">
2340                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_HEADER_MODE</constant>&nbsp;</entry>
2341                 <entry>enum&nbsp;v4l2_mpeg_video_header_mode</entry>
2342               </row>
2343               <row><entry spanname="descr">Determines whether the header is returned as the first buffer or is
2344 it returned together with the first frame. Applicable to encoders.
2345 Possible values are:</entry>
2346               </row>
2347               <row>
2348                 <entrytbl spanname="descr" cols="2">
2349                   <tbody valign="top">
2350                     <row>
2351                       <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE</constant>&nbsp;</entry>
2352                       <entry>The stream header is returned separately in the first buffer.</entry>
2353                     </row>
2354                     <row>
2355                       <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_JOINED_WITH_1ST_FRAME</constant>&nbsp;</entry>
2356                       <entry>The stream header is returned together with the first encoded frame.</entry>
2357                     </row>
2358                   </tbody>
2359                 </entrytbl>
2360               </row>
2361               <row><entry></entry></row>
2362               <row>
2363                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER</constant>&nbsp;</entry>
2364                 <entry>boolean</entry>
2365               </row><row><entry spanname="descr">Repeat the video sequence headers. Repeating these
2366 headers makes random access to the video stream easier. Applicable to the MPEG1, 2 and 4 encoder.</entry>
2367               </row>
2368               <row>
2369                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER</constant>&nbsp;</entry>
2370                 <entry>boolean</entry>
2371               </row><row><entry spanname="descr">Enabled the deblocking post processing filter for MPEG4 decoder.
2372 Applicable to the MPEG4 decoder.</entry>
2373               </row>
2374               <row><entry></entry></row>
2375               <row>
2376                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_RES</constant>&nbsp;</entry>
2377                 <entry>integer</entry>
2378               </row><row><entry spanname="descr">vop_time_increment_resolution value for MPEG4. Applicable to the MPEG4 encoder.</entry>
2379               </row>
2380               <row><entry></entry></row>
2381               <row>
2382                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_INC</constant>&nbsp;</entry>
2383                 <entry>integer</entry>
2384               </row><row><entry spanname="descr">vop_time_increment value for MPEG4. Applicable to the MPEG4 encoder.</entry>
2385               </row>
2386
2387               <row><entry></entry></row>
2388               <row>
2389                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FRAME_PACKING</constant>&nbsp;</entry>
2390                 <entry>boolean</entry>
2391               </row>
2392               <row><entry spanname="descr">Enable generation of frame packing supplemental enhancement information in the encoded bitstream.
2393 The frame packing SEI message contains the arrangement of L and R planes for 3D viewing. Applicable to the H264 encoder.</entry>
2394               </row>
2395
2396               <row><entry></entry></row>
2397               <row>
2398                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_CURRENT_FRAME_0</constant>&nbsp;</entry>
2399                 <entry>boolean</entry>
2400               </row>
2401               <row><entry spanname="descr">Sets current frame as frame0 in frame packing SEI.
2402 Applicable to the H264 encoder.</entry>
2403               </row>
2404
2405               <row><entry></entry></row>
2406               <row id="v4l2-mpeg-video-h264-sei-fp-arrangement-type">
2407                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE</constant>&nbsp;</entry>
2408                 <entry>enum&nbsp;v4l2_mpeg_video_h264_sei_fp_arrangement_type</entry>
2409               </row>
2410               <row><entry spanname="descr">Frame packing arrangement type for H264 SEI.
2411 Applicable to the H264 encoder.
2412 Possible values are:</entry>
2413               </row>
2414               <row>
2415                 <entrytbl spanname="descr" cols="2">
2416                   <tbody valign="top">
2417                     <row>
2418                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_CHEKERBOARD</constant>&nbsp;</entry>
2419                       <entry>Pixels are alternatively from L and R.</entry>
2420                     </row>
2421                     <row>
2422                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_COLUMN</constant>&nbsp;</entry>
2423                       <entry>L and R are interlaced by column.</entry>
2424                     </row>
2425                     <row>
2426                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_ROW</constant>&nbsp;</entry>
2427                       <entry>L and R are interlaced by row.</entry>
2428                     </row>
2429                     <row>
2430                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_SIDE_BY_SIDE</constant>&nbsp;</entry>
2431                       <entry>L is on the left, R on the right.</entry>
2432                     </row>
2433                     <row>
2434                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TOP_BOTTOM</constant>&nbsp;</entry>
2435                       <entry>L is on top, R on bottom.</entry>
2436                     </row>
2437                     <row>
2438                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TEMPORAL</constant>&nbsp;</entry>
2439                       <entry>One view per frame.</entry>
2440                     </row>
2441                   </tbody>
2442                 </entrytbl>
2443               </row>
2444
2445               <row><entry></entry></row>
2446               <row>
2447                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO</constant>&nbsp;</entry>
2448                 <entry>boolean</entry>
2449               </row>
2450               <row><entry spanname="descr">Enables flexible macroblock ordering in the encoded bitstream. It is a technique
2451 used for restructuring the ordering of macroblocks in pictures. Applicable to the H264 encoder.</entry>
2452               </row>
2453
2454               <row><entry></entry></row>
2455               <row id="v4l2-mpeg-video-h264-fmo-map-type">
2456                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE</constant>&nbsp;</entry>
2457                 <entry>enum&nbsp;v4l2_mpeg_video_h264_fmo_map_type</entry>
2458               </row>
2459               <row><entry spanname="descr">When using FMO, the map type divides the image in different scan patterns of macroblocks.
2460 Applicable to the H264 encoder.
2461 Possible values are:</entry>
2462               </row>
2463               <row>
2464                 <entrytbl spanname="descr" cols="2">
2465                   <tbody valign="top">
2466                     <row>
2467                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_INTERLEAVED_SLICES</constant>&nbsp;</entry>
2468                       <entry>Slices are interleaved one after other with macroblocks in run length order.</entry>
2469                     </row>
2470                     <row>
2471                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_SCATTERED_SLICES</constant>&nbsp;</entry>
2472                       <entry>Scatters the macroblocks based on a mathematical function known to both encoder and decoder.</entry>
2473                     </row>
2474                     <row>
2475                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_FOREGROUND_WITH_LEFT_OVER</constant>&nbsp;</entry>
2476                       <entry>Macroblocks arranged in rectangular areas or regions of interest.</entry>
2477                     </row>
2478                     <row>
2479                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_BOX_OUT</constant>&nbsp;</entry>
2480                       <entry>Slice groups grow in a cyclic way from centre to outwards.</entry>
2481                     </row>
2482                     <row>
2483                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_RASTER_SCAN</constant>&nbsp;</entry>
2484                       <entry>Slice groups grow in raster scan pattern from left to right.</entry>
2485                     </row>
2486                     <row>
2487                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_WIPE_SCAN</constant>&nbsp;</entry>
2488                       <entry>Slice groups grow in wipe scan pattern from top to bottom.</entry>
2489                     </row>
2490                     <row>
2491                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_EXPLICIT</constant>&nbsp;</entry>
2492                       <entry>User defined map type.</entry>
2493                     </row>
2494                   </tbody>
2495                 </entrytbl>
2496               </row>
2497
2498               <row><entry></entry></row>
2499               <row>
2500                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_SLICE_GROUP</constant>&nbsp;</entry>
2501                 <entry>integer</entry>
2502               </row>
2503               <row><entry spanname="descr">Number of slice groups in FMO.
2504 Applicable to the H264 encoder.</entry>
2505               </row>
2506
2507               <row><entry></entry></row>
2508               <row id="v4l2-mpeg-video-h264-fmo-change-direction">
2509                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_DIRECTION</constant>&nbsp;</entry>
2510                 <entry>enum&nbsp;v4l2_mpeg_video_h264_fmo_change_dir</entry>
2511               </row>
2512               <row><entry spanname="descr">Specifies a direction of the slice group change for raster and wipe maps.
2513 Applicable to the H264 encoder.
2514 Possible values are:</entry>
2515               </row>
2516               <row>
2517                 <entrytbl spanname="descr" cols="2">
2518                   <tbody valign="top">
2519                     <row>
2520                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_RIGHT</constant>&nbsp;</entry>
2521                       <entry>Raster scan or wipe right.</entry>
2522                     </row>
2523                     <row>
2524                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_LEFT</constant>&nbsp;</entry>
2525                       <entry>Reverse raster scan or wipe left.</entry>
2526                     </row>
2527                   </tbody>
2528                 </entrytbl>
2529               </row>
2530
2531               <row><entry></entry></row>
2532               <row>
2533                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_RATE</constant>&nbsp;</entry>
2534                 <entry>integer</entry>
2535               </row>
2536               <row><entry spanname="descr">Specifies the size of the first slice group for raster and wipe map.
2537 Applicable to the H264 encoder.</entry>
2538               </row>
2539
2540               <row><entry></entry></row>
2541               <row>
2542                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_RUN_LENGTH</constant>&nbsp;</entry>
2543                 <entry>integer</entry>
2544               </row>
2545               <row><entry spanname="descr">Specifies the number of consecutive macroblocks for the interleaved map.
2546 Applicable to the H264 encoder.</entry>
2547               </row>
2548
2549               <row><entry></entry></row>
2550               <row>
2551                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO</constant>&nbsp;</entry>
2552                 <entry>boolean</entry>
2553               </row>
2554               <row><entry spanname="descr">Enables arbitrary slice ordering in encoded bitstream.
2555 Applicable to the H264 encoder.</entry>
2556               </row>
2557
2558               <row><entry></entry></row>
2559               <row>
2560                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO_SLICE_ORDER</constant>&nbsp;</entry>
2561                 <entry>integer</entry>
2562               </row><row><entry spanname="descr">Specifies the slice order in ASO. Applicable to the H264 encoder.
2563 The supplied 32-bit integer is interpreted as follows (bit
2564 0 = least significant bit):</entry>
2565               </row>
2566               <row>
2567                 <entrytbl spanname="descr" cols="2">
2568                   <tbody valign="top">
2569                     <row>
2570                       <entry>Bit 0:15</entry>
2571                       <entry>Slice ID</entry>
2572                     </row>
2573                     <row>
2574                       <entry>Bit 16:32</entry>
2575                       <entry>Slice position or order</entry>
2576                     </row>
2577                   </tbody>
2578                 </entrytbl>
2579               </row>
2580
2581               <row><entry></entry></row>
2582               <row>
2583                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING</constant>&nbsp;</entry>
2584                 <entry>boolean</entry>
2585               </row>
2586               <row><entry spanname="descr">Enables H264 hierarchical coding.
2587 Applicable to the H264 encoder.</entry>
2588               </row>
2589
2590               <row><entry></entry></row>
2591               <row id="v4l2-mpeg-video-h264-hierarchical-coding-type">
2592                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_TYPE</constant>&nbsp;</entry>
2593                 <entry>enum&nbsp;v4l2_mpeg_video_h264_hierarchical_coding_type</entry>
2594               </row>
2595               <row><entry spanname="descr">Specifies the hierarchical coding type.
2596 Applicable to the H264 encoder.
2597 Possible values are:</entry>
2598               </row>
2599               <row>
2600                 <entrytbl spanname="descr" cols="2">
2601                   <tbody valign="top">
2602                     <row>
2603                       <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_B</constant>&nbsp;</entry>
2604                       <entry>Hierarchical B coding.</entry>
2605                     </row>
2606                     <row>
2607                       <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_P</constant>&nbsp;</entry>
2608                       <entry>Hierarchical P coding.</entry>
2609                     </row>
2610                   </tbody>
2611                 </entrytbl>
2612               </row>
2613
2614               <row><entry></entry></row>
2615               <row>
2616                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER</constant>&nbsp;</entry>
2617                 <entry>integer</entry>
2618               </row>
2619               <row><entry spanname="descr">Specifies the number of hierarchical coding layers.
2620 Applicable to the H264 encoder.</entry>
2621               </row>
2622
2623               <row><entry></entry></row>
2624               <row>
2625                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP</constant>&nbsp;</entry>
2626                 <entry>integer</entry>
2627               </row><row><entry spanname="descr">Specifies a user defined QP for each layer. Applicable to the H264 encoder.
2628 The supplied 32-bit integer is interpreted as follows (bit
2629 0 = least significant bit):</entry>
2630               </row>
2631               <row>
2632                 <entrytbl spanname="descr" cols="2">
2633                   <tbody valign="top">
2634                     <row>
2635                       <entry>Bit 0:15</entry>
2636                       <entry>QP value</entry>
2637                     </row>
2638                     <row>
2639                       <entry>Bit 16:32</entry>
2640                       <entry>Layer number</entry>
2641                     </row>
2642                   </tbody>
2643                 </entrytbl>
2644               </row>
2645
2646             </tbody>
2647           </tgroup>
2648         </table>
2649       </section>
2650
2651       <section>
2652         <title>MFC 5.1 MPEG Controls</title>
2653
2654         <para>The following MPEG class controls deal with MPEG
2655 decoding and encoding settings that are specific to the Multi Format Codec 5.1 device present
2656 in the S5P family of SoCs by Samsung.
2657 </para>
2658
2659         <table pgwide="1" frame="none" id="mfc51-control-id">
2660           <title>MFC 5.1 Control IDs</title>
2661           <tgroup cols="4">
2662             <colspec colname="c1" colwidth="1*" />
2663             <colspec colname="c2" colwidth="6*" />
2664             <colspec colname="c3" colwidth="2*" />
2665             <colspec colname="c4" colwidth="6*" />
2666             <spanspec namest="c1" nameend="c2" spanname="id" />
2667             <spanspec namest="c2" nameend="c4" spanname="descr" />
2668             <thead>
2669               <row>
2670                 <entry spanname="id" align="left">ID</entry>
2671                 <entry align="left">Type</entry>
2672               </row><row><entry spanname="descr" align="left">Description</entry>
2673               </row>
2674             </thead>
2675             <tbody valign="top">
2676               <row><entry></entry></row>
2677               <row>
2678                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY_ENABLE</constant>&nbsp;</entry>
2679                 <entry>integer</entry>
2680               </row><row><entry spanname="descr">If the display delay is enabled then the decoder has to return a
2681 CAPTURE buffer after processing a certain number of OUTPUT buffers. If this number is low, then it may result in
2682 buffers not being dequeued in display order. In addition hardware may still use those buffers as reference, thus
2683 application should not write to those buffers. This feature can be used for example for generating thumbnails of videos.
2684 Applicable to the H264 decoder.
2685               </entry>
2686               </row>
2687               <row><entry></entry></row>
2688               <row>
2689                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant>&nbsp;</entry>
2690                 <entry>integer</entry>
2691               </row><row><entry spanname="descr">Display delay value for H264 decoder.
2692 The decoder is forced to return a decoded frame after the set 'display delay' number of frames. If this number is
2693 low it may result in frames returned out of dispaly order, in addition the hardware may still be using the returned buffer
2694 as a reference picture for subsequent frames.
2695 </entry>
2696               </row>
2697               <row><entry></entry></row>
2698               <row>
2699                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P</constant>&nbsp;</entry>
2700                 <entry>integer</entry>
2701               </row><row><entry spanname="descr">The number of reference pictures used for encoding a P picture.
2702 Applicable to the H264 encoder.</entry>
2703               </row>
2704               <row><entry></entry></row>
2705               <row>
2706                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING</constant>&nbsp;</entry>
2707                 <entry>boolean</entry>
2708               </row><row><entry spanname="descr">Padding enable in the encoder - use a color instead of repeating border pixels.
2709 Applicable to encoders.</entry>
2710               </row>
2711               <row><entry></entry></row>
2712               <row>
2713                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV</constant>&nbsp;</entry>
2714                 <entry>integer</entry>
2715               </row><row><entry spanname="descr">Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit
2716 0 = least significant bit):</entry>
2717               </row>
2718               <row>
2719                 <entrytbl spanname="descr" cols="2">
2720                   <tbody valign="top">
2721                     <row>
2722                       <entry>Bit 0:7</entry>
2723                       <entry>V chrominance information</entry>
2724                     </row>
2725                     <row>
2726                       <entry>Bit 8:15</entry>
2727                       <entry>U chrominance information</entry>
2728                     </row>
2729                     <row>
2730                       <entry>Bit 16:23</entry>
2731                       <entry>Y luminance information</entry>
2732                     </row>
2733                     <row>
2734                       <entry>Bit 24:31</entry>
2735                       <entry>Must be zero.</entry>
2736                     </row>
2737                   </tbody>
2738                 </entrytbl>
2739               </row>
2740               <row><entry></entry></row>
2741               <row>
2742                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF</constant>&nbsp;</entry>
2743                 <entry>integer</entry>
2744               </row><row><entry spanname="descr">Reaction coefficient for MFC rate control. Applicable to encoders.
2745 <para>Note 1: Valid only when the frame level RC is enabled.</para>
2746 <para>Note 2: For tight CBR, this field must be small (ex. 2 ~ 10).
2747 For VBR, this field must be large (ex. 100 ~ 1000).</para>
2748 <para>Note 3: It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).</para>
2749 </entry>
2750               </row>
2751               <row><entry></entry></row>
2752               <row>
2753                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK</constant>&nbsp;</entry>
2754                 <entry>boolean</entry>
2755               </row><row><entry spanname="descr">Adaptive rate control for dark region.
2756 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2757 Applicable to the H264 encoder.</entry>
2758               </row>
2759               <row><entry></entry></row>
2760               <row>
2761                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH</constant>&nbsp;</entry>
2762                 <entry>boolean</entry>
2763               </row><row><entry spanname="descr">Adaptive rate control for smooth region.
2764 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2765 Applicable to the H264 encoder.</entry>
2766               </row>
2767               <row><entry></entry></row>
2768               <row>
2769                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC</constant>&nbsp;</entry>
2770                 <entry>boolean</entry>
2771               </row><row><entry spanname="descr">Adaptive rate control for static region.
2772 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2773 Applicable to the H264 encoder.</entry>
2774               </row>
2775               <row><entry></entry></row>
2776               <row>
2777                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY</constant>&nbsp;</entry>
2778                 <entry>boolean</entry>
2779               </row><row><entry spanname="descr">Adaptive rate control for activity region.
2780 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2781 Applicable to the H264 encoder.</entry>
2782               </row>
2783               <row><entry></entry></row>
2784               <row id="v4l2-mpeg-mfc51-video-frame-skip-mode">
2785                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE</constant>&nbsp;</entry>
2786                 <entry>enum&nbsp;v4l2_mpeg_mfc51_video_frame_skip_mode</entry>
2787               </row>
2788               <row><entry spanname="descr">
2789 Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then
2790 a chosen data limit then the frame will be skipped.
2791 Possible values are:</entry>
2792               </row>
2793               <row>
2794                 <entrytbl spanname="descr" cols="2">
2795                   <tbody valign="top">
2796                     <row>
2797                       <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED</constant>&nbsp;</entry>
2798                       <entry>Frame skip mode is disabled.</entry>
2799                     </row>
2800                     <row>
2801                       <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT</constant>&nbsp;</entry>
2802                       <entry>Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.</entry>
2803                     </row>
2804                     <row>
2805                       <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_BUF_LIMIT</constant>&nbsp;</entry>
2806                       <entry>Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.</entry>
2807                     </row>
2808                   </tbody>
2809                 </entrytbl>
2810               </row>
2811               <row><entry></entry></row>
2812               <row>
2813                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT</constant>&nbsp;</entry>
2814                 <entry>integer</entry>
2815               </row><row><entry spanname="descr">Enable rate-control with fixed target bit.
2816 If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate
2817 for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the
2818 overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case
2819 the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the
2820 average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that
2821 the stream will meet tight bandwidth contraints. Applicable to encoders.
2822 </entry>
2823               </row>
2824               <row><entry></entry></row>
2825               <row id="v4l2-mpeg-mfc51-video-force-frame-type">
2826                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE</constant>&nbsp;</entry>
2827                 <entry>enum&nbsp;v4l2_mpeg_mfc51_video_force_frame_type</entry>
2828               </row>
2829               <row><entry spanname="descr">Force a frame type for the next queued buffer. Applicable to encoders.
2830 Possible values are:</entry>
2831               </row>
2832               <row>
2833                 <entrytbl spanname="descr" cols="2">
2834                   <tbody valign="top">
2835                     <row>
2836                       <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED</constant>&nbsp;</entry>
2837                       <entry>Forcing a specific frame type disabled.</entry>
2838                     </row>
2839                     <row>
2840                       <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME</constant>&nbsp;</entry>
2841                       <entry>Force an I-frame.</entry>
2842                     </row>
2843                     <row>
2844                       <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED</constant>&nbsp;</entry>
2845                       <entry>Force a non-coded frame.</entry>
2846                     </row>
2847                   </tbody>
2848                 </entrytbl>
2849               </row>
2850             </tbody>
2851           </tgroup>
2852         </table>
2853       </section>
2854
2855       <section>
2856         <title>CX2341x MPEG Controls</title>
2857
2858         <para>The following MPEG class controls deal with MPEG
2859 encoding settings that are specific to the Conexant CX23415 and
2860 CX23416 MPEG encoding chips.</para>
2861
2862         <table pgwide="1" frame="none" id="cx2341x-control-id">
2863           <title>CX2341x Control IDs</title>
2864           <tgroup cols="4">
2865             <colspec colname="c1" colwidth="1*" />
2866             <colspec colname="c2" colwidth="6*" />
2867             <colspec colname="c3" colwidth="2*" />
2868             <colspec colname="c4" colwidth="6*" />
2869             <spanspec namest="c1" nameend="c2" spanname="id" />
2870             <spanspec namest="c2" nameend="c4" spanname="descr" />
2871             <thead>
2872               <row>
2873                 <entry spanname="id" align="left">ID</entry>
2874                 <entry align="left">Type</entry>
2875               </row><row><entry spanname="descr" align="left">Description</entry>
2876               </row>
2877             </thead>
2878             <tbody valign="top">
2879               <row><entry></entry></row>
2880               <row id="v4l2-mpeg-cx2341x-video-spatial-filter-mode">
2881                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE</constant>&nbsp;</entry>
2882                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_spatial_filter_mode</entry>
2883               </row><row><entry spanname="descr">Sets the Spatial
2884 Filter mode (default <constant>MANUAL</constant>). Possible values
2885 are:</entry>
2886               </row>
2887               <row>
2888                 <entrytbl spanname="descr" cols="2">
2889                   <tbody valign="top">
2890                     <row>
2891                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL</constant>&nbsp;</entry>
2892                       <entry>Choose the filter manually</entry>
2893                     </row>
2894                     <row>
2895                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO</constant>&nbsp;</entry>
2896                       <entry>Choose the filter automatically</entry>
2897                     </row>
2898                   </tbody>
2899                 </entrytbl>
2900               </row>
2901               <row><entry></entry></row>
2902               <row>
2903                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER</constant>&nbsp;</entry>
2904                 <entry>integer&nbsp;(0-15)</entry>
2905               </row><row><entry spanname="descr">The setting for the
2906 Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)</entry>
2907               </row>
2908               <row><entry></entry></row>
2909               <row id="luma-spatial-filter-type">
2910                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE</constant>&nbsp;</entry>
2911                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_luma_spatial_filter_type</entry>
2912               </row><row><entry spanname="descr">Select the algorithm
2913 to use for the Luma Spatial Filter (default
2914 <constant>1D_HOR</constant>). Possible values:</entry>
2915               </row>
2916               <row>
2917                 <entrytbl spanname="descr" cols="2">
2918                   <tbody valign="top">
2919                     <row>
2920                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF</constant>&nbsp;</entry>
2921                       <entry>No filter</entry>
2922                     </row>
2923                     <row>
2924                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR</constant>&nbsp;</entry>
2925                       <entry>One-dimensional horizontal</entry>
2926                     </row>
2927                     <row>
2928                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT</constant>&nbsp;</entry>
2929                       <entry>One-dimensional vertical</entry>
2930                     </row>
2931                     <row>
2932                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE</constant>&nbsp;</entry>
2933                       <entry>Two-dimensional separable</entry>
2934                     </row>
2935                     <row>
2936                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE</constant>&nbsp;</entry>
2937                       <entry>Two-dimensional symmetrical
2938 non-separable</entry>
2939                     </row>
2940                   </tbody>
2941                 </entrytbl>
2942               </row>
2943               <row><entry></entry></row>
2944               <row id="chroma-spatial-filter-type">
2945                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE</constant>&nbsp;</entry>
2946                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type</entry>
2947               </row><row><entry spanname="descr">Select the algorithm
2948 for the Chroma Spatial Filter (default <constant>1D_HOR</constant>).
2949 Possible values are:</entry>
2950               </row>
2951               <row>
2952                 <entrytbl spanname="descr" cols="2">
2953                   <tbody valign="top">
2954                     <row>
2955                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF</constant>&nbsp;</entry>
2956                       <entry>No filter</entry>
2957                     </row>
2958                     <row>
2959                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR</constant>&nbsp;</entry>
2960                       <entry>One-dimensional horizontal</entry>
2961                     </row>
2962                   </tbody>
2963                 </entrytbl>
2964               </row>
2965               <row><entry></entry></row>
2966               <row id="v4l2-mpeg-cx2341x-video-temporal-filter-mode">
2967                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE</constant>&nbsp;</entry>
2968                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_temporal_filter_mode</entry>
2969               </row><row><entry spanname="descr">Sets the Temporal
2970 Filter mode (default <constant>MANUAL</constant>). Possible values
2971 are:</entry>
2972               </row>
2973               <row>
2974                 <entrytbl spanname="descr" cols="2">
2975                   <tbody valign="top">
2976                     <row>
2977                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL</constant>&nbsp;</entry>
2978                       <entry>Choose the filter manually</entry>
2979                     </row>
2980                     <row>
2981                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO</constant>&nbsp;</entry>
2982                       <entry>Choose the filter automatically</entry>
2983                     </row>
2984                   </tbody>
2985                 </entrytbl>
2986               </row>
2987               <row><entry></entry></row>
2988               <row>
2989                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER</constant>&nbsp;</entry>
2990                 <entry>integer&nbsp;(0-31)</entry>
2991               </row><row><entry spanname="descr">The setting for the
2992 Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale
2993 capturing and 0 for scaled capturing.)</entry>
2994               </row>
2995               <row><entry></entry></row>
2996               <row id="v4l2-mpeg-cx2341x-video-median-filter-type">
2997                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE</constant>&nbsp;</entry>
2998                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_median_filter_type</entry>
2999               </row><row><entry spanname="descr">Median Filter Type
3000 (default <constant>OFF</constant>). Possible values are:</entry>
3001               </row>
3002               <row>
3003                 <entrytbl spanname="descr" cols="2">
3004                   <tbody valign="top">
3005                     <row>
3006                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF</constant>&nbsp;</entry>
3007                       <entry>No filter</entry>
3008                     </row>
3009                     <row>
3010                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR</constant>&nbsp;</entry>
3011                       <entry>Horizontal filter</entry>
3012                     </row>
3013                     <row>
3014                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT</constant>&nbsp;</entry>
3015                       <entry>Vertical filter</entry>
3016                     </row>
3017                     <row>
3018                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT</constant>&nbsp;</entry>
3019                       <entry>Horizontal and vertical filter</entry>
3020                     </row>
3021                     <row>
3022                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG</constant>&nbsp;</entry>
3023                       <entry>Diagonal filter</entry>
3024                     </row>
3025                   </tbody>
3026                 </entrytbl>
3027               </row>
3028               <row><entry></entry></row>
3029               <row>
3030                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM</constant>&nbsp;</entry>
3031                 <entry>integer&nbsp;(0-255)</entry>
3032               </row><row><entry spanname="descr">Threshold above which
3033 the luminance median filter is enabled (default 0)</entry>
3034               </row>
3035               <row><entry></entry></row>
3036               <row>
3037                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP</constant>&nbsp;</entry>
3038                 <entry>integer&nbsp;(0-255)</entry>
3039               </row><row><entry spanname="descr">Threshold below which
3040 the luminance median filter is enabled (default 255)</entry>
3041               </row>
3042               <row><entry></entry></row>
3043               <row>
3044                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM</constant>&nbsp;</entry>
3045                 <entry>integer&nbsp;(0-255)</entry>
3046               </row><row><entry spanname="descr">Threshold above which
3047 the chroma median filter is enabled (default 0)</entry>
3048               </row>
3049               <row><entry></entry></row>
3050               <row>
3051                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP</constant>&nbsp;</entry>
3052                 <entry>integer&nbsp;(0-255)</entry>
3053               </row><row><entry spanname="descr">Threshold below which
3054 the chroma median filter is enabled (default 255)</entry>
3055               </row>
3056               <row><entry></entry></row>
3057               <row>
3058                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS</constant>&nbsp;</entry>
3059                 <entry>boolean</entry>
3060               </row>
3061               <row><entry spanname="descr">The CX2341X MPEG encoder
3062 can insert one empty MPEG-2 PES packet into the stream between every
3063 four video frames. The packet size is 2048 bytes, including the
3064 packet_start_code_prefix and stream_id fields. The stream_id is 0xBF
3065 (private stream 2). The payload consists of 0x00 bytes, to be filled
3066 in by the application. 0 = do not insert, 1 = insert packets.</entry>
3067               </row>
3068             </tbody>
3069           </tgroup>
3070         </table>
3071       </section>
3072
3073     <section>
3074       <title>VPX Control Reference</title>
3075
3076       <para>The VPX controls include controls for encoding parameters
3077       of VPx video codec.</para>
3078
3079       <table pgwide="1" frame="none" id="vpx-control-id">
3080       <title>VPX Control IDs</title>
3081
3082       <tgroup cols="4">
3083         <colspec colname="c1" colwidth="1*" />
3084         <colspec colname="c2" colwidth="6*" />
3085         <colspec colname="c3" colwidth="2*" />
3086         <colspec colname="c4" colwidth="6*" />
3087         <spanspec namest="c1" nameend="c2" spanname="id" />
3088         <spanspec namest="c2" nameend="c4" spanname="descr" />
3089         <thead>
3090           <row>
3091             <entry spanname="id" align="left">ID</entry>
3092             <entry align="left">Type</entry>
3093           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
3094           </row>
3095         </thead>
3096         <tbody valign="top">
3097           <row><entry></entry></row>
3098
3099               <row><entry></entry></row>
3100               <row id="v4l2-vpx-num-partitions">
3101                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS</constant></entry>
3102                 <entry>enum v4l2_vp8_num_partitions</entry>
3103               </row>
3104               <row><entry spanname="descr">The number of token partitions to use in VP8 encoder.
3105 Possible values are:</entry>
3106               </row>
3107               <row>
3108                 <entrytbl spanname="descr" cols="2">
3109                   <tbody valign="top">
3110                     <row>
3111                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_PARTITION</constant></entry>
3112                       <entry>1 coefficient partition</entry>
3113                     </row>
3114                     <row>
3115                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_PARTITIONS</constant></entry>
3116                       <entry>2 coefficient partitions</entry>
3117                     </row>
3118                     <row>
3119                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_4_PARTITIONS</constant></entry>
3120                       <entry>4 coefficient partitions</entry>
3121                     </row>
3122                     <row>
3123                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_8_PARTITIONS</constant></entry>
3124                       <entry>8 coefficient partitions</entry>
3125                     </row>
3126                   </tbody>
3127                 </entrytbl>
3128               </row>
3129
3130               <row><entry></entry></row>
3131               <row>
3132                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_IMD_DISABLE_4X4</constant></entry>
3133                 <entry>boolean</entry>
3134               </row>
3135               <row><entry spanname="descr">Setting this prevents intra 4x4 mode in the intra mode decision.</entry>
3136               </row>
3137
3138               <row><entry></entry></row>
3139               <row id="v4l2-vpx-num-ref-frames">
3140                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_REF_FRAMES</constant></entry>
3141                 <entry>enum v4l2_vp8_num_ref_frames</entry>
3142               </row>
3143               <row><entry spanname="descr">The number of reference pictures for encoding P frames.
3144 Possible values are:</entry>
3145               </row>
3146               <row>
3147                 <entrytbl spanname="descr" cols="2">
3148                   <tbody valign="top">
3149                     <row>
3150                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_REF_FRAME</constant></entry>
3151                       <entry>Last encoded frame will be searched</entry>
3152                     </row>
3153                     <row>
3154                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_REF_FRAME</constant></entry>
3155                       <entry>Two frames will be searched among the last encoded frame, the golden frame
3156 and the alternate reference (altref) frame. The encoder implementation will decide which two are chosen.</entry>
3157                     </row>
3158                     <row>
3159                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_3_REF_FRAME</constant></entry>
3160                       <entry>The last encoded frame, the golden frame and the altref frame will be searched.</entry>
3161                     </row>
3162                   </tbody>
3163                 </entrytbl>
3164               </row>
3165
3166               <row><entry></entry></row>
3167               <row>
3168                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_LEVEL</constant></entry>
3169                 <entry>integer</entry>
3170               </row>
3171               <row><entry spanname="descr">Indicates the loop filter level. The adjustment of the loop
3172 filter level is done via a delta value against a baseline loop filter value.</entry>
3173               </row>
3174
3175               <row><entry></entry></row>
3176               <row>
3177                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_SHARPNESS</constant></entry>
3178                 <entry>integer</entry>
3179               </row>
3180               <row><entry spanname="descr">This parameter affects the loop filter. Anything above
3181 zero weakens the deblocking effect on the loop filter.</entry>
3182               </row>
3183
3184               <row><entry></entry></row>
3185               <row>
3186                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD</constant></entry>
3187                 <entry>integer</entry>
3188               </row>
3189               <row><entry spanname="descr">Sets the refresh period for the golden frame. The period is defined
3190 in number of frames. For a value of 'n', every nth frame starting from the first key frame will be taken as a golden frame.
3191 For eg. for encoding sequence of 0, 1, 2, 3, 4, 5, 6, 7 where the golden frame refresh period is set as 4, the frames
3192 0, 4, 8 etc will be taken as the golden frames as frame 0 is always a key frame.</entry>
3193               </row>
3194
3195               <row><entry></entry></row>
3196               <row id="v4l2-vpx-golden-frame-sel">
3197                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL</constant></entry>
3198                 <entry>enum v4l2_vp8_golden_frame_sel</entry>
3199               </row>
3200               <row><entry spanname="descr">Selects the golden frame for encoding.
3201 Possible values are:</entry>
3202               </row>
3203               <row>
3204                 <entrytbl spanname="descr" cols="2">
3205                   <tbody valign="top">
3206                     <row>
3207                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_PREV</constant></entry>
3208                       <entry>Use the (n-2)th frame as a golden frame, current frame index being 'n'.</entry>
3209                     </row>
3210                     <row>
3211                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_REF_PERIOD</constant></entry>
3212                       <entry>Use the previous specific frame indicated by
3213 V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD as a golden frame.</entry>
3214                     </row>
3215                   </tbody>
3216                 </entrytbl>
3217               </row>
3218
3219               <row><entry></entry></row>
3220               <row>
3221                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MIN_QP</constant></entry>
3222                 <entry>integer</entry>
3223               </row>
3224               <row><entry spanname="descr">Minimum quantization parameter for VP8.</entry>
3225               </row>
3226
3227               <row><entry></entry></row>
3228               <row>
3229                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MAX_QP</constant></entry>
3230                 <entry>integer</entry>
3231               </row>
3232               <row><entry spanname="descr">Maximum quantization parameter for VP8.</entry>
3233               </row>
3234
3235               <row><entry></entry></row>
3236               <row>
3237                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_I_FRAME_QP</constant>&nbsp;</entry>
3238                 <entry>integer</entry>
3239               </row>
3240               <row><entry spanname="descr">Quantization parameter for an I frame for VP8.</entry>
3241               </row>
3242
3243               <row><entry></entry></row>
3244               <row>
3245                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP</constant>&nbsp;</entry>
3246                 <entry>integer</entry>
3247               </row>
3248               <row><entry spanname="descr">Quantization parameter for a P frame for VP8.</entry>
3249               </row>
3250
3251               <row><entry></entry></row>
3252               <row>
3253                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_PROFILE</constant>&nbsp;</entry>
3254                 <entry>integer</entry>
3255               </row>
3256               <row><entry spanname="descr">Select the desired profile for VPx encoder.
3257 Acceptable values are 0, 1, 2 and 3 corresponding to encoder profiles 0, 1, 2 and 3.</entry>
3258               </row>
3259
3260           <row><entry></entry></row>
3261         </tbody>
3262       </tgroup>
3263       </table>
3264
3265       </section>
3266     </section>
3267
3268     <section id="camera-controls">
3269       <title>Camera Control Reference</title>
3270
3271       <para>The Camera class includes controls for mechanical (or
3272 equivalent digital) features of a device such as controllable lenses
3273 or sensors.</para>
3274
3275     <table pgwide="1" frame="none" id="camera-control-id">
3276       <title>Camera Control IDs</title>
3277       <tgroup cols="4">
3278         <colspec colname="c1" colwidth="1*" />
3279         <colspec colname="c2" colwidth="6*" />
3280         <colspec colname="c3" colwidth="2*" />
3281         <colspec colname="c4" colwidth="6*" />
3282         <spanspec namest="c1" nameend="c2" spanname="id" />
3283         <spanspec namest="c2" nameend="c4" spanname="descr" />
3284         <thead>
3285           <row>
3286             <entry spanname="id" align="left">ID</entry>
3287             <entry align="left">Type</entry>
3288           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
3289           </row>
3290         </thead>
3291         <tbody valign="top">
3292           <row><entry></entry></row>
3293           <row>
3294             <entry spanname="id"><constant>V4L2_CID_CAMERA_CLASS</constant>&nbsp;</entry>
3295             <entry>class</entry>
3296           </row><row><entry spanname="descr">The Camera class
3297 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
3298 description of this control class.</entry>
3299           </row>
3300           <row><entry></entry></row>
3301
3302           <row id="v4l2-exposure-auto-type">
3303             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO</constant>&nbsp;</entry>
3304             <entry>enum&nbsp;v4l2_exposure_auto_type</entry>
3305           </row><row><entry spanname="descr">Enables automatic
3306 adjustments of the exposure time and/or iris aperture. The effect of
3307 manual changes of the exposure time or iris aperture while these
3308 features are enabled is undefined, drivers should ignore such
3309 requests. Possible values are:</entry>
3310           </row>
3311           <row>
3312             <entrytbl spanname="descr" cols="2">
3313               <tbody valign="top">
3314                 <row>
3315                   <entry><constant>V4L2_EXPOSURE_AUTO</constant>&nbsp;</entry>
3316                       <entry>Automatic exposure time, automatic iris
3317 aperture.</entry>
3318                 </row>
3319                 <row>
3320                   <entry><constant>V4L2_EXPOSURE_MANUAL</constant>&nbsp;</entry>
3321                   <entry>Manual exposure time, manual iris.</entry>
3322                 </row>
3323                 <row>
3324                   <entry><constant>V4L2_EXPOSURE_SHUTTER_PRIORITY</constant>&nbsp;</entry>
3325                   <entry>Manual exposure time, auto iris.</entry>
3326                 </row>
3327                 <row>
3328                   <entry><constant>V4L2_EXPOSURE_APERTURE_PRIORITY</constant>&nbsp;</entry>
3329                   <entry>Auto exposure time, manual iris.</entry>
3330                 </row>
3331               </tbody>
3332             </entrytbl>
3333           </row>
3334           <row><entry></entry></row>
3335
3336           <row>
3337             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_ABSOLUTE</constant>&nbsp;</entry>
3338             <entry>integer</entry>
3339           </row><row><entry spanname="descr">Determines the exposure
3340 time of the camera sensor. The exposure time is limited by the frame
3341 interval. Drivers should interpret the values as 100 &micro;s units,
3342 where the value 1 stands for 1/10000th of a second, 10000 for 1 second
3343 and 100000 for 10 seconds.</entry>
3344           </row>
3345           <row><entry></entry></row>
3346
3347           <row>
3348             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO_PRIORITY</constant>&nbsp;</entry>
3349             <entry>boolean</entry>
3350           </row><row><entry spanname="descr">When
3351 <constant>V4L2_CID_EXPOSURE_AUTO</constant> is set to
3352 <constant>AUTO</constant> or <constant>APERTURE_PRIORITY</constant>,
3353 this control determines if the device may dynamically vary the frame
3354 rate. By default this feature is disabled (0) and the frame rate must
3355 remain constant.</entry>
3356           </row>
3357           <row><entry></entry></row>
3358
3359           <row>
3360             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_BIAS</constant>&nbsp;</entry>
3361             <entry>integer menu</entry>
3362           </row><row><entry spanname="descr"> Determines the automatic
3363 exposure compensation, it is effective only when <constant>V4L2_CID_EXPOSURE_AUTO</constant>
3364 control is set to <constant>AUTO</constant>, <constant>SHUTTER_PRIORITY </constant>
3365 or <constant>APERTURE_PRIORITY</constant>.
3366 It is expressed in terms of EV, drivers should interpret the values as 0.001 EV
3367 units, where the value 1000 stands for +1 EV.
3368 <para>Increasing the exposure compensation value is equivalent to decreasing
3369 the exposure value (EV) and will increase the amount of light at the image
3370 sensor. The camera performs the exposure compensation by adjusting absolute
3371 exposure time and/or aperture.</para></entry>
3372           </row>
3373           <row><entry></entry></row>
3374
3375           <row id="v4l2-exposure-metering">
3376             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_METERING</constant>&nbsp;</entry>
3377             <entry>enum&nbsp;v4l2_exposure_metering</entry>
3378           </row><row><entry spanname="descr">Determines how the camera measures
3379 the amount of light available for the frame exposure. Possible values are:</entry>
3380           </row>
3381           <row>
3382             <entrytbl spanname="descr" cols="2">
3383               <tbody valign="top">
3384                 <row>
3385                   <entry><constant>V4L2_EXPOSURE_METERING_AVERAGE</constant>&nbsp;</entry>
3386                   <entry>Use the light information coming from the entire frame
3387 and average giving no weighting to any particular portion of the metered area.
3388                   </entry>
3389                 </row>
3390                 <row>
3391                   <entry><constant>V4L2_EXPOSURE_METERING_CENTER_WEIGHTED</constant>&nbsp;</entry>
3392                   <entry>Average the light information coming from the entire frame
3393 giving priority to the center of the metered area.</entry>
3394                 </row>
3395                 <row>
3396                   <entry><constant>V4L2_EXPOSURE_METERING_SPOT</constant>&nbsp;</entry>
3397                   <entry>Measure only very small area at the center of the frame.</entry>
3398                 </row>
3399                 <row>
3400                   <entry><constant>V4L2_EXPOSURE_METERING_MATRIX</constant>&nbsp;</entry>
3401                   <entry>A multi-zone metering. The light intensity is measured
3402 in several points of the frame and the the results are combined. The
3403 algorithm of the zones selection and their significance in calculating the
3404 final value is device dependent.</entry>
3405                 </row>
3406               </tbody>
3407             </entrytbl>
3408           </row>
3409           <row><entry></entry></row>
3410
3411           <row>
3412             <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant>&nbsp;</entry>
3413             <entry>integer</entry>
3414           </row><row><entry spanname="descr">This control turns the
3415 camera horizontally by the specified amount. The unit is undefined. A
3416 positive value moves the camera to the right (clockwise when viewed
3417 from above), a negative value to the left. A value of zero does not
3418 cause motion. This is a write-only control.</entry>
3419           </row>
3420           <row><entry></entry></row>
3421
3422           <row>
3423             <entry spanname="id"><constant>V4L2_CID_TILT_RELATIVE</constant>&nbsp;</entry>
3424             <entry>integer</entry>
3425           </row><row><entry spanname="descr">This control turns the
3426 camera vertically by the specified amount. The unit is undefined. A
3427 positive value moves the camera up, a negative value down. A value of
3428 zero does not cause motion. This is a write-only control.</entry>
3429           </row>
3430           <row><entry></entry></row>
3431
3432           <row>
3433             <entry spanname="id"><constant>V4L2_CID_PAN_RESET</constant>&nbsp;</entry>
3434             <entry>button</entry>
3435           </row><row><entry spanname="descr">When this control is set,
3436 the camera moves horizontally to the default position.</entry>
3437           </row>
3438           <row><entry></entry></row>
3439
3440           <row>
3441             <entry spanname="id"><constant>V4L2_CID_TILT_RESET</constant>&nbsp;</entry>
3442             <entry>button</entry>
3443           </row><row><entry spanname="descr">When this control is set,
3444 the camera moves vertically to the default position.</entry>
3445           </row>
3446           <row><entry></entry></row>
3447
3448           <row>
3449             <entry spanname="id"><constant>V4L2_CID_PAN_ABSOLUTE</constant>&nbsp;</entry>
3450             <entry>integer</entry>
3451           </row><row><entry spanname="descr">This control
3452 turns the camera horizontally to the specified position. Positive
3453 values move the camera to the right (clockwise when viewed from above),
3454 negative values to the left. Drivers should interpret the values as arc
3455 seconds, with valid values between -180 * 3600 and +180 * 3600
3456 inclusive.</entry>
3457           </row>
3458           <row><entry></entry></row>
3459
3460           <row>
3461             <entry spanname="id"><constant>V4L2_CID_TILT_ABSOLUTE</constant>&nbsp;</entry>
3462             <entry>integer</entry>
3463           </row><row><entry spanname="descr">This control
3464 turns the camera vertically to the specified position. Positive values
3465 move the camera up, negative values down. Drivers should interpret the
3466 values as arc seconds, with valid values between -180 * 3600 and +180
3467 * 3600 inclusive.</entry>
3468           </row>
3469           <row><entry></entry></row>
3470
3471           <row>
3472             <entry spanname="id"><constant>V4L2_CID_FOCUS_ABSOLUTE</constant>&nbsp;</entry>
3473             <entry>integer</entry>
3474           </row><row><entry spanname="descr">This control sets the
3475 focal point of the camera to the specified position. The unit is
3476 undefined. Positive values set the focus closer to the camera,
3477 negative values towards infinity.</entry>
3478           </row>
3479           <row><entry></entry></row>
3480
3481           <row>
3482             <entry spanname="id"><constant>V4L2_CID_FOCUS_RELATIVE</constant>&nbsp;</entry>
3483             <entry>integer</entry>
3484           </row><row><entry spanname="descr">This control moves the
3485 focal point of the camera by the specified amount. The unit is
3486 undefined. Positive values move the focus closer to the camera,
3487 negative values towards infinity. This is a write-only control.</entry>
3488           </row>
3489           <row><entry></entry></row>
3490
3491           <row>
3492             <entry spanname="id"><constant>V4L2_CID_FOCUS_AUTO</constant>&nbsp;</entry>
3493             <entry>boolean</entry>
3494           </row><row><entry spanname="descr">Enables continuous automatic
3495 focus adjustments. The effect of manual focus adjustments while this feature
3496 is enabled is undefined, drivers should ignore such requests.</entry>
3497           </row>
3498           <row><entry></entry></row>
3499
3500           <row>
3501             <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_START</constant>&nbsp;</entry>
3502             <entry>button</entry>
3503           </row><row><entry spanname="descr">Starts single auto focus process.
3504 The effect of setting this control when <constant>V4L2_CID_FOCUS_AUTO</constant>
3505 is set to <constant>TRUE</constant> (1) is undefined, drivers should ignore
3506 such requests.</entry>
3507           </row>
3508           <row><entry></entry></row>
3509
3510           <row>
3511             <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_STOP</constant>&nbsp;</entry>
3512             <entry>button</entry>
3513           </row><row><entry spanname="descr">Aborts automatic focusing
3514 started with <constant>V4L2_CID_AUTO_FOCUS_START</constant> control. It is
3515 effective only when the continuous autofocus is disabled, that is when
3516 <constant>V4L2_CID_FOCUS_AUTO</constant> control is set to <constant>FALSE
3517 </constant> (0).</entry>
3518           </row>
3519           <row><entry></entry></row>
3520
3521           <row id="v4l2-auto-focus-status">
3522             <entry spanname="id">
3523               <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant>&nbsp;</entry>
3524             <entry>bitmask</entry>
3525           </row>
3526           <row><entry spanname="descr">The automatic focus status. This is a read-only
3527           control.</entry>
3528           </row>
3529           <row>
3530             <entrytbl spanname="descr" cols="2">
3531               <tbody valign="top">
3532                 <row>
3533                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_IDLE</constant>&nbsp;</entry>
3534                   <entry>Automatic focus is not active.</entry>
3535                 </row>
3536                 <row>
3537                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_BUSY</constant>&nbsp;</entry>
3538                   <entry>Automatic focusing is in progress.</entry>
3539                 </row>
3540                 <row>
3541                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_REACHED</constant>&nbsp;</entry>
3542                   <entry>Focus has been reached.</entry>
3543                 </row>
3544                 <row>
3545                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_FAILED</constant>&nbsp;</entry>
3546                   <entry>Automatic focus has failed, the driver will not
3547                   transition from this state until another action is
3548                   performed by an application.</entry>
3549                 </row>
3550               </tbody>
3551             </entrytbl>
3552           </row>
3553           <row><entry spanname="descr">
3554 Setting <constant>V4L2_LOCK_FOCUS</constant> lock bit of the <constant>V4L2_CID_3A_LOCK
3555 </constant> control may stop updates of the <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant>
3556 control value.</entry>
3557           </row>
3558           <row><entry></entry></row>
3559
3560           <row id="v4l2-auto-focus-range">
3561             <entry spanname="id">
3562               <constant>V4L2_CID_AUTO_FOCUS_RANGE</constant>&nbsp;</entry>
3563             <entry>enum&nbsp;v4l2_auto_focus_range</entry>
3564           </row>
3565           <row><entry spanname="descr">Determines auto focus distance range
3566 for which lens may be adjusted. </entry>
3567           </row>
3568           <row>
3569             <entrytbl spanname="descr" cols="2">
3570               <tbody valign="top">
3571                 <row>
3572                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_AUTO</constant>&nbsp;</entry>
3573                   <entry>The camera automatically selects the focus range.</entry>
3574                 </row>
3575                 <row>
3576                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_NORMAL</constant>&nbsp;</entry>
3577                   <entry>Normal distance range, limited for best automatic focus
3578 performance.</entry>
3579                 </row>
3580                 <row>
3581                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_MACRO</constant>&nbsp;</entry>
3582                   <entry>Macro (close-up) auto focus. The camera will
3583 use its minimum possible distance for auto focus.</entry>
3584                 </row>
3585                 <row>
3586                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_INFINITY</constant>&nbsp;</entry>
3587                   <entry>The lens is set to focus on an object at infinite distance.</entry>
3588                 </row>
3589               </tbody>
3590             </entrytbl>
3591           </row>
3592           <row><entry></entry></row>
3593
3594           <row>
3595             <entry spanname="id"><constant>V4L2_CID_ZOOM_ABSOLUTE</constant>&nbsp;</entry>
3596             <entry>integer</entry>
3597           </row><row><entry spanname="descr">Specify the objective lens
3598 focal length as an absolute value. The zoom unit is driver-specific and its
3599 value should be a positive integer.</entry>
3600           </row>
3601           <row><entry></entry></row>
3602
3603           <row>
3604             <entry spanname="id"><constant>V4L2_CID_ZOOM_RELATIVE</constant>&nbsp;</entry>
3605             <entry>integer</entry>
3606           </row><row><entry spanname="descr">Specify the objective lens
3607 focal length relatively to the current value. Positive values move the zoom
3608 lens group towards the telephoto direction, negative values towards the
3609 wide-angle direction. The zoom unit is driver-specific. This is a write-only control.</entry>
3610           </row>
3611           <row><entry></entry></row>
3612
3613           <row>
3614             <entry spanname="id"><constant>V4L2_CID_ZOOM_CONTINUOUS</constant>&nbsp;</entry>
3615             <entry>integer</entry>
3616           </row><row><entry spanname="descr">Move the objective lens group
3617 at the specified speed until it reaches physical device limits or until an
3618 explicit request to stop the movement. A positive value moves the zoom lens
3619 group towards the telephoto direction. A value of zero stops the zoom lens
3620 group movement. A negative value moves the zoom lens group towards the
3621 wide-angle direction. The zoom speed unit is driver-specific.</entry>
3622           </row>
3623           <row><entry></entry></row>
3624
3625           <row>
3626             <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant>&nbsp;</entry>
3627             <entry>integer</entry>
3628           </row><row><entry spanname="descr">This control sets the
3629 camera's aperture to the specified value. The unit is undefined.
3630 Larger values open the iris wider, smaller values close it.</entry>
3631           </row>
3632           <row><entry></entry></row>
3633
3634           <row>
3635             <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant>&nbsp;</entry>
3636             <entry>integer</entry>
3637           </row><row><entry spanname="descr">This control modifies the
3638 camera's aperture by the specified amount. The unit is undefined.
3639 Positive values open the iris one step further, negative values close
3640 it one step further. This is a write-only control.</entry>
3641           </row>
3642           <row><entry></entry></row>
3643
3644           <row>
3645             <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant>&nbsp;</entry>
3646             <entry>boolean</entry>
3647           </row><row><entry spanname="descr">Prevent video from being acquired
3648 by the camera. When this control is set to <constant>TRUE</constant> (1), no
3649 image can be captured by the camera. Common means to enforce privacy are
3650 mechanical obturation of the sensor and firmware image processing, but the
3651 device is not restricted to these methods. Devices that implement the privacy
3652 control must support read access and may support write access.</entry>
3653           </row>
3654
3655           <row>
3656             <entry spanname="id"><constant>V4L2_CID_BAND_STOP_FILTER</constant>&nbsp;</entry>
3657             <entry>integer</entry>
3658           </row><row><entry spanname="descr">Switch the band-stop filter of a
3659 camera sensor on or off, or specify its strength. Such band-stop filters can
3660 be used, for example, to filter out the fluorescent light component.</entry>
3661           </row>
3662           <row><entry></entry></row>
3663
3664           <row id="v4l2-auto-n-preset-white-balance">
3665             <entry spanname="id"><constant>V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE</constant>&nbsp;</entry>
3666             <entry>enum&nbsp;v4l2_auto_n_preset_white_balance</entry>
3667           </row><row><entry spanname="descr">Sets white balance to automatic,
3668 manual or a preset. The presets determine color temperature of the light as
3669 a hint to the camera for white balance adjustments resulting in most accurate
3670 color representation. The following white balance presets are listed in order
3671 of increasing color temperature.</entry>
3672           </row>
3673           <row>
3674             <entrytbl spanname="descr" cols="2">
3675               <tbody valign="top">
3676                 <row>
3677                   <entry><constant>V4L2_WHITE_BALANCE_MANUAL</constant>&nbsp;</entry>
3678                   <entry>Manual white balance.</entry>
3679                 </row>
3680                 <row>
3681                   <entry><constant>V4L2_WHITE_BALANCE_AUTO</constant>&nbsp;</entry>
3682                   <entry>Automatic white balance adjustments.</entry>
3683                 </row>
3684                 <row>
3685                   <entry><constant>V4L2_WHITE_BALANCE_INCANDESCENT</constant>&nbsp;</entry>
3686                   <entry>White balance setting for incandescent (tungsten) lighting.
3687 It generally cools down the colors and corresponds approximately to 2500...3500 K
3688 color temperature range.</entry>
3689                 </row>
3690                 <row>
3691                   <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT</constant>&nbsp;</entry>
3692                   <entry>White balance preset for fluorescent lighting.
3693 It corresponds approximately to 4000...5000 K color temperature.</entry>
3694                 </row>
3695                 <row>
3696                   <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT_H</constant>&nbsp;</entry>
3697                   <entry>With this setting the camera will compensate for
3698 fluorescent H lighting.</entry>
3699                 </row>
3700                 <row>
3701                   <entry><constant>V4L2_WHITE_BALANCE_HORIZON</constant>&nbsp;</entry>
3702                   <entry>White balance setting for horizon daylight.
3703 It corresponds approximately to 5000 K color temperature.</entry>
3704                 </row>
3705                 <row>
3706                   <entry><constant>V4L2_WHITE_BALANCE_DAYLIGHT</constant>&nbsp;</entry>
3707                   <entry>White balance preset for daylight (with clear sky).
3708 It corresponds approximately to 5000...6500 K color temperature.</entry>
3709                 </row>
3710                 <row>
3711                   <entry><constant>V4L2_WHITE_BALANCE_FLASH</constant>&nbsp;</entry>
3712                   <entry>With this setting the camera will compensate for the flash
3713 light. It slightly warms up the colors and corresponds roughly to 5000...5500 K
3714 color temperature.</entry>
3715                 </row>
3716                 <row>
3717                   <entry><constant>V4L2_WHITE_BALANCE_CLOUDY</constant>&nbsp;</entry>
3718                   <entry>White balance preset for moderately overcast sky.
3719 This option corresponds approximately to 6500...8000 K color temperature
3720 range.</entry>
3721                 </row>
3722                 <row>
3723                   <entry><constant>V4L2_WHITE_BALANCE_SHADE</constant>&nbsp;</entry>
3724                   <entry>White balance preset for shade or heavily overcast
3725 sky. It corresponds approximately to 9000...10000 K color temperature.
3726 </entry>
3727                 </row>
3728               </tbody>
3729             </entrytbl>
3730           </row>
3731           <row><entry></entry></row>
3732
3733           <row id="v4l2-wide-dynamic-range">
3734             <entry spanname="id"><constant>V4L2_CID_WIDE_DYNAMIC_RANGE</constant></entry>
3735             <entry>boolean</entry>
3736           </row>
3737           <row>
3738             <entry spanname="descr">Enables or disables the camera's wide dynamic
3739 range feature. This feature allows to obtain clear images in situations where
3740 intensity of the illumination varies significantly throughout the scene, i.e.
3741 there are simultaneously very dark and very bright areas. It is most commonly
3742 realized in cameras by combining two subsequent frames with different exposure
3743 times. <footnote id="ctypeconv"><para> This control may be changed to a menu
3744 control in the future, if more options are required.</para></footnote></entry>
3745           </row>
3746           <row><entry></entry></row>
3747
3748           <row id="v4l2-image-stabilization">
3749             <entry spanname="id"><constant>V4L2_CID_IMAGE_STABILIZATION</constant></entry>
3750             <entry>boolean</entry>
3751           </row>
3752           <row>
3753             <entry spanname="descr">Enables or disables image stabilization.
3754               <footnoteref linkend="ctypeconv"/></entry>
3755           </row>
3756           <row><entry></entry></row>
3757
3758           <row>
3759             <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY</constant>&nbsp;</entry>
3760             <entry>integer menu</entry>
3761           </row><row><entry spanname="descr">Determines ISO equivalent of an
3762 image sensor indicating the sensor's sensitivity to light. The numbers are
3763 expressed in arithmetic scale, as per <xref linkend="iso12232" /> standard,
3764 where doubling the sensor sensitivity is represented by doubling the numerical
3765 ISO value. Applications should interpret the values as standard ISO values
3766 multiplied by 1000, e.g. control value 800 stands for ISO 0.8. Drivers will
3767 usually support only a subset of standard ISO values. The effect of setting
3768 this control while the <constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant>
3769 control is set to a value other than <constant>V4L2_CID_ISO_SENSITIVITY_MANUAL
3770 </constant> is undefined, drivers should ignore such requests.</entry>
3771           </row>
3772           <row><entry></entry></row>
3773
3774           <row id="v4l2-iso-sensitivity-auto-type">
3775             <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant>&nbsp;</entry>
3776             <entry>enum&nbsp;v4l2_iso_sensitivity_type</entry>
3777           </row><row><entry spanname="descr">Enables or disables automatic ISO
3778 sensitivity adjustments.</entry>
3779           </row>
3780           <row>
3781             <entrytbl spanname="descr" cols="2">
3782               <tbody valign="top">
3783                 <row>
3784                   <entry><constant>V4L2_CID_ISO_SENSITIVITY_MANUAL</constant>&nbsp;</entry>
3785                   <entry>Manual ISO sensitivity.</entry>
3786                 </row>
3787                 <row>
3788                   <entry><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant>&nbsp;</entry>
3789                   <entry>Automatic ISO sensitivity adjustments.</entry>
3790                 </row>
3791               </tbody>
3792             </entrytbl>
3793           </row>
3794           <row><entry></entry></row>
3795
3796           <row id="v4l2-scene-mode">
3797             <entry spanname="id"><constant>V4L2_CID_SCENE_MODE</constant>&nbsp;</entry>
3798             <entry>enum&nbsp;v4l2_scene_mode</entry>
3799           </row><row><entry spanname="descr">This control allows to select
3800 scene programs as the camera automatic modes optimized for common shooting
3801 scenes. Within these modes the camera determines best exposure, aperture,
3802 focusing, light metering, white balance and equivalent sensitivity. The
3803 controls of those parameters are influenced by the scene mode control.
3804 An exact behavior in each mode is subject to the camera specification.
3805
3806 <para>When the scene mode feature is not used, this control should be set to
3807 <constant>V4L2_SCENE_MODE_NONE</constant> to make sure the other possibly
3808 related controls are accessible. The following scene programs are defined:
3809 </para>
3810 </entry>
3811           </row>
3812           <row>
3813             <entrytbl spanname="descr" cols="2">
3814               <tbody valign="top">
3815                 <row>
3816                   <entry><constant>V4L2_SCENE_MODE_NONE</constant>&nbsp;</entry>
3817                   <entry>The scene mode feature is disabled.</entry>
3818                 </row>
3819                 <row>
3820                   <entry><constant>V4L2_SCENE_MODE_BACKLIGHT</constant>&nbsp;</entry>
3821                   <entry>Backlight. Compensates for dark shadows when light is
3822                   coming from behind a subject, also by automatically turning
3823                   on the flash.</entry>
3824                 </row>
3825                 <row>
3826                   <entry><constant>V4L2_SCENE_MODE_BEACH_SNOW</constant>&nbsp;</entry>
3827                   <entry>Beach and snow. This mode compensates for all-white or
3828 bright scenes, which tend to look gray and low contrast, when camera's automatic
3829 exposure is based on an average scene brightness. To compensate, this mode
3830 automatically slightly overexposes the frames. The white balance may also be
3831 adjusted to compensate for the fact that reflected snow looks bluish rather
3832 than white.</entry>
3833                 </row>
3834                 <row>
3835                   <entry><constant>V4L2_SCENE_MODE_CANDLELIGHT</constant>&nbsp;</entry>
3836                   <entry>Candle light. The camera generally raises the ISO
3837 sensitivity and lowers the shutter speed. This mode compensates for relatively
3838 close subject in the scene. The flash is disabled in order to preserve the
3839 ambiance of the light.</entry>
3840                 </row>
3841                 <row>
3842                   <entry><constant>V4L2_SCENE_MODE_DAWN_DUSK</constant>&nbsp;</entry>
3843                   <entry>Dawn and dusk. Preserves the colors seen in low
3844 natural light before dusk and after down. The camera may turn off the flash,
3845 and automatically focus at infinity. It will usually boost saturation and
3846 lower the shutter speed.</entry>
3847                 </row>
3848                 <row>
3849                   <entry><constant>V4L2_SCENE_MODE_FALL_COLORS</constant>&nbsp;</entry>
3850                   <entry>Fall colors. Increases saturation and adjusts white
3851 balance for color enhancement. Pictures of autumn leaves get saturated reds
3852 and yellows.</entry>
3853                 </row>
3854                 <row>
3855                   <entry><constant>V4L2_SCENE_MODE_FIREWORKS</constant>&nbsp;</entry>
3856                   <entry>Fireworks. Long exposure times are used to capture
3857 the expanding burst of light from a firework. The camera may invoke image
3858 stabilization.</entry>
3859                 </row>
3860                 <row>
3861                   <entry><constant>V4L2_SCENE_MODE_LANDSCAPE</constant>&nbsp;</entry>
3862                   <entry>Landscape. The camera may choose a small aperture to
3863 provide deep depth of field and long exposure duration to help capture detail
3864 in dim light conditions. The focus is fixed at infinity. Suitable for distant
3865 and wide scenery.</entry>
3866                 </row>
3867                 <row>
3868                   <entry><constant>V4L2_SCENE_MODE_NIGHT</constant>&nbsp;</entry>
3869                   <entry>Night, also known as Night Landscape. Designed for low
3870 light conditions, it preserves detail in the dark areas without blowing out bright
3871 objects. The camera generally sets itself to a medium-to-high ISO sensitivity,
3872 with a relatively long exposure time, and turns flash off. As such, there will be
3873 increased image noise and the possibility of blurred image.</entry>
3874                 </row>
3875                 <row>
3876                   <entry><constant>V4L2_SCENE_MODE_PARTY_INDOOR</constant>&nbsp;</entry>
3877                   <entry>Party and indoor. Designed to capture indoor scenes
3878 that are lit by indoor background lighting as well as the flash. The camera
3879 usually increases ISO sensitivity, and adjusts exposure for the low light
3880 conditions.</entry>
3881                 </row>
3882                 <row>
3883                   <entry><constant>V4L2_SCENE_MODE_PORTRAIT</constant>&nbsp;</entry>
3884                   <entry>Portrait. The camera adjusts the aperture so that the
3885 depth of field is reduced, which helps to isolate the subject against a smooth
3886 background. Most cameras recognize the presence of faces in the scene and focus
3887 on them. The color hue is adjusted to enhance skin tones. The intensity of the
3888 flash is often reduced.</entry>
3889                 </row>
3890                 <row>
3891                   <entry><constant>V4L2_SCENE_MODE_SPORTS</constant>&nbsp;</entry>
3892                   <entry>Sports. Significantly increases ISO and uses a fast
3893 shutter speed to freeze motion of rapidly-moving subjects. Increased image
3894 noise may be seen in this mode.</entry>
3895                 </row>
3896                 <row>
3897                   <entry><constant>V4L2_SCENE_MODE_SUNSET</constant>&nbsp;</entry>
3898                   <entry>Sunset. Preserves deep hues seen in sunsets and
3899 sunrises. It bumps up the saturation.</entry>
3900                 </row>
3901                 <row>
3902                   <entry><constant>V4L2_SCENE_MODE_TEXT</constant>&nbsp;</entry>
3903                   <entry>Text. It applies extra contrast and sharpness, it is
3904 typically a black-and-white mode optimized for readability. Automatic focus
3905 may be switched to close-up mode and this setting may also involve some
3906 lens-distortion correction.</entry>
3907                 </row>
3908               </tbody>
3909             </entrytbl>
3910           </row>
3911           <row><entry></entry></row>
3912
3913           <row>
3914             <entry spanname="id"><constant>V4L2_CID_3A_LOCK</constant></entry>
3915             <entry>bitmask</entry>
3916           </row>
3917           <row>
3918             <entry spanname="descr">This control locks or unlocks the automatic
3919 focus, exposure and white balance. The automatic adjustments can be paused
3920 independently by setting the corresponding lock bit to 1. The camera then retains
3921 the settings until the lock bit is cleared. The following lock bits are defined:
3922 </entry>
3923           </row>
3924           <row>
3925             <entrytbl spanname="descr" cols="2">
3926               <tbody valign="top">
3927                 <row>
3928                   <entry><constant>V4L2_LOCK_EXPOSURE</constant></entry>
3929                   <entry>Automatic exposure adjustments lock.</entry>
3930                 </row>
3931                 <row>
3932                   <entry><constant>V4L2_LOCK_WHITE_BALANCE</constant></entry>
3933                   <entry>Automatic white balance adjustments lock.</entry>
3934                 </row>
3935                 <row>
3936                   <entry><constant>V4L2_LOCK_FOCUS</constant></entry>
3937                   <entry>Automatic focus lock.</entry>
3938                 </row>
3939               </tbody>
3940             </entrytbl>
3941           </row>
3942           <row><entry spanname="descr">
3943 When a given algorithm is not enabled, drivers should ignore requests
3944 to lock it and should return no error. An example might be an application
3945 setting bit <constant>V4L2_LOCK_WHITE_BALANCE</constant> when the
3946 <constant>V4L2_CID_AUTO_WHITE_BALANCE</constant> control is set to
3947 <constant>FALSE</constant>. The value of this control may be changed
3948 by exposure, white balance or focus controls.</entry>
3949           </row>
3950           <row><entry></entry></row>
3951
3952         </tbody>
3953       </tgroup>
3954     </table>
3955   </section>
3956
3957     <section id="fm-tx-controls">
3958       <title>FM Transmitter Control Reference</title>
3959
3960       <para>The FM Transmitter (FM_TX) class includes controls for common features of
3961 FM transmissions capable devices. Currently this class includes parameters for audio
3962 compression, pilot tone generation, audio deviation limiter, RDS transmission and
3963 tuning power features.</para>
3964
3965       <table pgwide="1" frame="none" id="fm-tx-control-id">
3966       <title>FM_TX Control IDs</title>
3967
3968       <tgroup cols="4">
3969         <colspec colname="c1" colwidth="1*" />
3970         <colspec colname="c2" colwidth="6*" />
3971         <colspec colname="c3" colwidth="2*" />
3972         <colspec colname="c4" colwidth="6*" />
3973         <spanspec namest="c1" nameend="c2" spanname="id" />
3974         <spanspec namest="c2" nameend="c4" spanname="descr" />
3975         <thead>
3976           <row>
3977             <entry spanname="id" align="left">ID</entry>
3978             <entry align="left">Type</entry>
3979           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
3980           </row>
3981         </thead>
3982         <tbody valign="top">
3983           <row><entry></entry></row>
3984           <row>
3985             <entry spanname="id"><constant>V4L2_CID_FM_TX_CLASS</constant>&nbsp;</entry>
3986             <entry>class</entry>
3987           </row><row><entry spanname="descr">The FM_TX class
3988 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
3989 description of this control class.</entry>
3990           </row>
3991           <row>
3992             <entry spanname="id"><constant>V4L2_CID_RDS_TX_DEVIATION</constant>&nbsp;</entry>
3993             <entry>integer</entry>
3994           </row>
3995           <row><entry spanname="descr">Configures RDS signal frequency deviation level in Hz.
3996 The range and step are driver-specific.</entry>
3997           </row>
3998           <row>
3999             <entry spanname="id"><constant>V4L2_CID_RDS_TX_PI</constant>&nbsp;</entry>
4000             <entry>integer</entry>
4001           </row>
4002           <row><entry spanname="descr">Sets the RDS Programme Identification field
4003 for transmission.</entry>
4004           </row>
4005           <row>
4006             <entry spanname="id"><constant>V4L2_CID_RDS_TX_PTY</constant>&nbsp;</entry>
4007             <entry>integer</entry>
4008           </row>
4009           <row><entry spanname="descr">Sets the RDS Programme Type field for transmission.
4010 This encodes up to 31 pre-defined programme types.</entry>
4011           </row>
4012           <row>
4013             <entry spanname="id"><constant>V4L2_CID_RDS_TX_PS_NAME</constant>&nbsp;</entry>
4014             <entry>string</entry>
4015           </row>
4016           <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission.
4017 It is intended for static display on a receiver. It is the primary aid to listeners in programme service
4018 identification and selection.  In Annex E of <xref linkend="iec62106" />, the RDS specification,
4019 there is a full description of the correct character encoding for Programme Service name strings.
4020 Also from RDS specification, PS is usually a single eight character text. However, it is also possible
4021 to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured
4022 with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry>
4023           </row>
4024           <row>
4025             <entry spanname="id"><constant>V4L2_CID_RDS_TX_RADIO_TEXT</constant>&nbsp;</entry>
4026             <entry>string</entry>
4027           </row>
4028           <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of
4029 what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names,
4030 programme-related information or any other text. In these cases, RadioText should be used in addition to
4031 <constant>V4L2_CID_RDS_TX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described
4032 in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being
4033 used to transmit it, either 32 (2A block) or 64 (2B block).  However, it is also possible
4034 to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured
4035 with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry>
4036           </row>
4037           <row>
4038             <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant>&nbsp;</entry>
4039             <entry>boolean</entry>
4040           </row>
4041           <row><entry spanname="descr">Enables or disables the audio deviation limiter feature.
4042 The limiter is useful when trying to maximize the audio volume, minimize receiver-generated
4043 distortion and prevent overmodulation.
4044 </entry>
4045           </row>
4046           <row>
4047             <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant>&nbsp;</entry>
4048             <entry>integer</entry>
4049           </row>
4050           <row><entry spanname="descr">Sets the audio deviation limiter feature release time.
4051 Unit is in useconds. Step and range are driver-specific.</entry>
4052           </row>
4053           <row>
4054             <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant>&nbsp;</entry>
4055             <entry>integer</entry>
4056           </row>
4057           <row><entry spanname="descr">Configures audio frequency deviation level in Hz.
4058 The range and step are driver-specific.</entry>
4059           </row>
4060           <row>
4061             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant>&nbsp;</entry>
4062             <entry>boolean</entry>
4063           </row>
4064           <row><entry spanname="descr">Enables or disables the audio compression feature.
4065 This feature amplifies signals below the threshold by a fixed gain and compresses audio
4066 signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry>
4067           </row>
4068           <row>
4069             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant>&nbsp;</entry>
4070             <entry>integer</entry>
4071           </row>
4072           <row><entry spanname="descr">Sets the gain for audio compression feature. It is
4073 a dB value. The range and step are driver-specific.</entry>
4074           </row>
4075           <row>
4076             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant>&nbsp;</entry>
4077             <entry>integer</entry>
4078           </row>
4079           <row><entry spanname="descr">Sets the threshold level for audio compression freature.
4080 It is a dB value. The range and step are driver-specific.</entry>
4081           </row>
4082           <row>
4083             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant>&nbsp;</entry>
4084             <entry>integer</entry>
4085           </row>
4086           <row><entry spanname="descr">Sets the attack time for audio compression feature.
4087 It is a useconds value. The range and step are driver-specific.</entry>
4088           </row>
4089           <row>
4090             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant>&nbsp;</entry>
4091             <entry>integer</entry>
4092           </row>
4093           <row><entry spanname="descr">Sets the release time for audio compression feature.
4094 It is a useconds value. The range and step are driver-specific.</entry>
4095           </row>
4096           <row>
4097             <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant>&nbsp;</entry>
4098             <entry>boolean</entry>
4099           </row>
4100           <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry>
4101           </row>
4102           <row>
4103             <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant>&nbsp;</entry>
4104             <entry>integer</entry>
4105           </row>
4106           <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is
4107 in Hz. The range and step are driver-specific.</entry>
4108           </row>
4109           <row>
4110             <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant>&nbsp;</entry>
4111             <entry>integer</entry>
4112           </row>
4113           <row><entry spanname="descr">Configures pilot tone frequency value. Unit is
4114 in Hz. The range and step are driver-specific.</entry>
4115           </row>
4116           <row>
4117             <entry spanname="id"><constant>V4L2_CID_TUNE_PREEMPHASIS</constant>&nbsp;</entry>
4118             <entry>enum v4l2_preemphasis</entry>
4119           </row>
4120           <row id="v4l2-preemphasis"><entry spanname="descr">Configures the pre-emphasis value for broadcasting.
4121 A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies.
4122 Depending on the region, a time constant of either 50 or 75 useconds is used. The enum&nbsp;v4l2_preemphasis
4123 defines possible values for pre-emphasis. Here they are:</entry>
4124         </row><row>
4125         <entrytbl spanname="descr" cols="2">
4126                   <tbody valign="top">
4127                     <row>
4128                       <entry><constant>V4L2_PREEMPHASIS_DISABLED</constant>&nbsp;</entry>
4129                       <entry>No pre-emphasis is applied.</entry>
4130                     </row>
4131                     <row>
4132                       <entry><constant>V4L2_PREEMPHASIS_50_uS</constant>&nbsp;</entry>
4133                       <entry>A pre-emphasis of 50 uS is used.</entry>
4134                     </row>
4135                     <row>
4136                       <entry><constant>V4L2_PREEMPHASIS_75_uS</constant>&nbsp;</entry>
4137                       <entry>A pre-emphasis of 75 uS is used.</entry>
4138                     </row>
4139                   </tbody>
4140                 </entrytbl>
4141
4142           </row>
4143           <row>
4144             <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant>&nbsp;</entry>
4145             <entry>integer</entry>
4146           </row>
4147           <row><entry spanname="descr">Sets the output power level for signal transmission.
4148 Unit is in dBuV. Range and step are driver-specific.</entry>
4149           </row>
4150           <row>
4151             <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant>&nbsp;</entry>
4152             <entry>integer</entry>
4153           </row>
4154           <row><entry spanname="descr">This selects the value of antenna tuning capacitor
4155 manually or automatically if set to zero. Unit, range and step are driver-specific.</entry>
4156           </row>
4157           <row><entry></entry></row>
4158         </tbody>
4159       </tgroup>
4160       </table>
4161
4162 <para>For more details about RDS specification, refer to
4163 <xref linkend="iec62106" /> document, from CENELEC.</para>
4164     </section>
4165
4166     <section id="flash-controls">
4167       <title>Flash Control Reference</title>
4168
4169       <note>
4170         <title>Experimental</title>
4171
4172         <para>This is an <link linkend="experimental">experimental</link>
4173 interface and may change in the future.</para>
4174       </note>
4175
4176       <para>
4177         The V4L2 flash controls are intended to provide generic access
4178         to flash controller devices. Flash controller devices are
4179         typically used in digital cameras.
4180       </para>
4181
4182       <para>
4183         The interface can support both LED and xenon flash devices. As
4184         of writing this, there is no xenon flash driver using this
4185         interface.
4186       </para>
4187
4188       <section id="flash-controls-use-cases">
4189         <title>Supported use cases</title>
4190
4191         <section>
4192           <title>Unsynchronised LED flash (software strobe)</title>
4193
4194           <para>
4195             Unsynchronised LED flash is controlled directly by the
4196             host as the sensor. The flash must be enabled by the host
4197             before the exposure of the image starts and disabled once
4198             it ends. The host is fully responsible for the timing of
4199             the flash.
4200           </para>
4201
4202           <para>Example of such device: Nokia N900.</para>
4203         </section>
4204
4205         <section>
4206           <title>Synchronised LED flash (hardware strobe)</title>
4207
4208           <para>
4209             The synchronised LED flash is pre-programmed by the host
4210             (power and timeout) but controlled by the sensor through a
4211             strobe signal from the sensor to the flash.
4212           </para>
4213
4214           <para>
4215             The sensor controls the flash duration and timing. This
4216             information typically must be made available to the
4217             sensor.
4218           </para>
4219
4220         </section>
4221
4222         <section>
4223           <title>LED flash as torch</title>
4224
4225           <para>
4226             LED flash may be used as torch in conjunction with another
4227             use case involving camera or individually.
4228           </para>
4229
4230
4231           <table pgwide="1" frame="none" id="flash-control-id">
4232           <title>Flash Control IDs</title>
4233
4234           <tgroup cols="4">
4235         <colspec colname="c1" colwidth="1*" />
4236         <colspec colname="c2" colwidth="6*" />
4237         <colspec colname="c3" colwidth="2*" />
4238         <colspec colname="c4" colwidth="6*" />
4239         <spanspec namest="c1" nameend="c2" spanname="id" />
4240         <spanspec namest="c2" nameend="c4" spanname="descr" />
4241         <thead>
4242           <row>
4243             <entry spanname="id" align="left">ID</entry>
4244             <entry align="left">Type</entry>
4245           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4246           </row>
4247         </thead>
4248         <tbody valign="top">
4249           <row><entry></entry></row>
4250           <row>
4251             <entry spanname="id"><constant>V4L2_CID_FLASH_CLASS</constant></entry>
4252             <entry>class</entry>
4253           </row>
4254           <row>
4255             <entry spanname="descr">The FLASH class descriptor.</entry>
4256           </row>
4257           <row>
4258             <entry spanname="id"><constant>V4L2_CID_FLASH_LED_MODE</constant></entry>
4259             <entry>menu</entry>
4260           </row>
4261           <row id="v4l2-flash-led-mode">
4262             <entry spanname="descr">Defines the mode of the flash LED,
4263             the high-power white LED attached to the flash controller.
4264             Setting this control may not be possible in presence of
4265             some faults. See V4L2_CID_FLASH_FAULT.</entry>
4266           </row>
4267           <row>
4268             <entrytbl spanname="descr" cols="2">
4269               <tbody valign="top">
4270                 <row>
4271                   <entry><constant>V4L2_FLASH_LED_MODE_NONE</constant></entry>
4272                   <entry>Off.</entry>
4273                 </row>
4274                 <row>
4275                   <entry><constant>V4L2_FLASH_LED_MODE_FLASH</constant></entry>
4276                   <entry>Flash mode.</entry>
4277                 </row>
4278                 <row>
4279                   <entry><constant>V4L2_FLASH_LED_MODE_TORCH</constant></entry>
4280                   <entry>Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY.</entry>
4281                 </row>
4282               </tbody>
4283             </entrytbl>
4284           </row>
4285           <row>
4286             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_SOURCE</constant></entry>
4287             <entry>menu</entry>
4288           </row>
4289           <row id="v4l2-flash-strobe-source"><entry
4290           spanname="descr">Defines the source of the flash LED
4291           strobe.</entry>
4292           </row>
4293           <row>
4294             <entrytbl spanname="descr" cols="2">
4295               <tbody valign="top">
4296                 <row>
4297                   <entry><constant>V4L2_FLASH_STROBE_SOURCE_SOFTWARE</constant></entry>
4298                   <entry>The flash strobe is triggered by using
4299                   the V4L2_CID_FLASH_STROBE control.</entry>
4300                 </row>
4301                 <row>
4302                   <entry><constant>V4L2_FLASH_STROBE_SOURCE_EXTERNAL</constant></entry>
4303                   <entry>The flash strobe is triggered by an
4304                   external source. Typically this is a sensor,
4305                   which makes it possible to synchronises the
4306                   flash strobe start to exposure start.</entry>
4307                 </row>
4308               </tbody>
4309             </entrytbl>
4310           </row>
4311           <row>
4312             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE</constant></entry>
4313             <entry>button</entry>
4314           </row>
4315           <row>
4316             <entry spanname="descr">Strobe flash. Valid when
4317             V4L2_CID_FLASH_LED_MODE is set to
4318             V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE
4319             is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this
4320             control may not be possible in presence of some faults.
4321             See V4L2_CID_FLASH_FAULT.</entry>
4322           </row>
4323           <row>
4324             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STOP</constant></entry>
4325             <entry>button</entry>
4326           </row>
4327           <row><entry spanname="descr">Stop flash strobe immediately.</entry>
4328           </row>
4329           <row>
4330             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STATUS</constant></entry>
4331             <entry>boolean</entry>
4332           </row>
4333           <row>
4334             <entry spanname="descr">Strobe status: whether the flash
4335             is strobing at the moment or not. This is a read-only
4336             control.</entry>
4337           </row>
4338           <row>
4339             <entry spanname="id"><constant>V4L2_CID_FLASH_TIMEOUT</constant></entry>
4340             <entry>integer</entry>
4341           </row>
4342           <row>
4343             <entry spanname="descr">Hardware timeout for flash. The
4344             flash strobe is stopped after this period of time has
4345             passed from the start of the strobe.</entry>
4346           </row>
4347           <row>
4348             <entry spanname="id"><constant>V4L2_CID_FLASH_INTENSITY</constant></entry>
4349             <entry>integer</entry>
4350           </row>
4351           <row>
4352             <entry spanname="descr">Intensity of the flash strobe when
4353             the flash LED is in flash mode
4354             (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps
4355             (mA) if possible.</entry>
4356           </row>
4357           <row>
4358             <entry spanname="id"><constant>V4L2_CID_FLASH_TORCH_INTENSITY</constant></entry>
4359             <entry>integer</entry>
4360           </row>
4361           <row>
4362             <entry spanname="descr">Intensity of the flash LED in
4363             torch mode (V4L2_FLASH_LED_MODE_TORCH). The unit should be
4364             milliamps (mA) if possible. Setting this control may not
4365             be possible in presence of some faults. See
4366             V4L2_CID_FLASH_FAULT.</entry>
4367           </row>
4368           <row>
4369             <entry spanname="id"><constant>V4L2_CID_FLASH_INDICATOR_INTENSITY</constant></entry>
4370             <entry>integer</entry>
4371           </row>
4372           <row>
4373             <entry spanname="descr">Intensity of the indicator LED.
4374             The indicator LED may be fully independent of the flash
4375             LED. The unit should be microamps (uA) if possible.</entry>
4376           </row>
4377           <row>
4378             <entry spanname="id"><constant>V4L2_CID_FLASH_FAULT</constant></entry>
4379             <entry>bitmask</entry>
4380           </row>
4381           <row>
4382             <entry spanname="descr">Faults related to the flash. The
4383             faults tell about specific problems in the flash chip
4384             itself or the LEDs attached to it. Faults may prevent
4385             further use of some of the flash controls. In particular,
4386             V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE
4387             if the fault affects the flash LED. Exactly which faults
4388             have such an effect is chip dependent. Reading the faults
4389             resets the control and returns the chip to a usable state
4390             if possible.</entry>
4391           </row>
4392           <row>
4393             <entrytbl spanname="descr" cols="2">
4394               <tbody valign="top">
4395                 <row>
4396                   <entry><constant>V4L2_FLASH_FAULT_OVER_VOLTAGE</constant></entry>
4397                   <entry>Flash controller voltage to the flash LED
4398                   has exceeded the limit specific to the flash
4399                   controller.</entry>
4400                 </row>
4401                 <row>
4402                   <entry><constant>V4L2_FLASH_FAULT_TIMEOUT</constant></entry>
4403                   <entry>The flash strobe was still on when
4404                   the timeout set by the user ---
4405                   V4L2_CID_FLASH_TIMEOUT control --- has expired.
4406                   Not all flash controllers may set this in all
4407                   such conditions.</entry>
4408                 </row>
4409                 <row>
4410                   <entry><constant>V4L2_FLASH_FAULT_OVER_TEMPERATURE</constant></entry>
4411                   <entry>The flash controller has overheated.</entry>
4412                 </row>
4413                 <row>
4414                   <entry><constant>V4L2_FLASH_FAULT_SHORT_CIRCUIT</constant></entry>
4415                   <entry>The short circuit protection of the flash
4416                   controller has been triggered.</entry>
4417                 </row>
4418                 <row>
4419                   <entry><constant>V4L2_FLASH_FAULT_OVER_CURRENT</constant></entry>
4420                   <entry>Current in the LED power supply has exceeded the limit
4421                   specific to the flash controller.</entry>
4422                 </row>
4423                 <row>
4424                   <entry><constant>V4L2_FLASH_FAULT_INDICATOR</constant></entry>
4425                   <entry>The flash controller has detected a short or open
4426                   circuit condition on the indicator LED.</entry>
4427                 </row>
4428                 <row>
4429                   <entry><constant>V4L2_FLASH_FAULT_UNDER_VOLTAGE</constant></entry>
4430                   <entry>Flash controller voltage to the flash LED
4431                   has been below the minimum limit specific to the flash
4432                   controller.</entry>
4433                 </row>
4434                 <row>
4435                   <entry><constant>V4L2_FLASH_FAULT_INPUT_VOLTAGE</constant></entry>
4436                   <entry>The input voltage of the flash controller is below
4437                   the limit under which strobing the flash at full current
4438                   will not be possible.The condition persists until this flag
4439                   is no longer set.</entry>
4440                 </row>
4441                 <row>
4442                   <entry><constant>V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE</constant></entry>
4443                   <entry>The temperature of the LED has exceeded its
4444                   allowed upper limit.</entry>
4445                 </row>
4446               </tbody>
4447             </entrytbl>
4448           </row>
4449           <row>
4450             <entry spanname="id"><constant>V4L2_CID_FLASH_CHARGE</constant></entry>
4451             <entry>boolean</entry>
4452           </row>
4453           <row><entry spanname="descr">Enable or disable charging of the xenon
4454           flash capacitor.</entry>
4455           </row>
4456           <row>
4457             <entry spanname="id"><constant>V4L2_CID_FLASH_READY</constant></entry>
4458             <entry>boolean</entry>
4459           </row>
4460           <row>
4461             <entry spanname="descr">Is the flash ready to strobe?
4462             Xenon flashes require their capacitors charged before
4463             strobing. LED flashes often require a cooldown period
4464             after strobe during which another strobe will not be
4465             possible. This is a read-only control.</entry>
4466           </row>
4467           <row><entry></entry></row>
4468         </tbody>
4469           </tgroup>
4470           </table>
4471         </section>
4472       </section>
4473     </section>
4474
4475     <section id="jpeg-controls">
4476       <title>JPEG Control Reference</title>
4477       <para>The JPEG class includes controls for common features of JPEG
4478       encoders and decoders. Currently it includes features for codecs
4479       implementing progressive baseline DCT compression process with
4480       Huffman entrophy coding.</para>
4481       <table pgwide="1" frame="none" id="jpeg-control-id">
4482       <title>JPEG Control IDs</title>
4483
4484       <tgroup cols="4">
4485         <colspec colname="c1" colwidth="1*" />
4486         <colspec colname="c2" colwidth="6*" />
4487         <colspec colname="c3" colwidth="2*" />
4488         <colspec colname="c4" colwidth="6*" />
4489         <spanspec namest="c1" nameend="c2" spanname="id" />
4490         <spanspec namest="c2" nameend="c4" spanname="descr" />
4491         <thead>
4492           <row>
4493             <entry spanname="id" align="left">ID</entry>
4494             <entry align="left">Type</entry>
4495           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4496           </row>
4497         </thead>
4498         <tbody valign="top">
4499           <row><entry></entry></row>
4500           <row>
4501             <entry spanname="id"><constant>V4L2_CID_JPEG_CLASS</constant>&nbsp;</entry>
4502             <entry>class</entry>
4503           </row><row><entry spanname="descr">The JPEG class descriptor. Calling
4504           &VIDIOC-QUERYCTRL; for this control will return a description of this
4505           control class.
4506
4507         </entry>
4508           </row>
4509           <row>
4510             <entry spanname="id"><constant>V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant></entry>
4511             <entry>menu</entry>
4512           </row>
4513           <row id="v4l2-jpeg-chroma-subsampling">
4514             <entry spanname="descr">The chroma subsampling factors describe how
4515             each component of an input image is sampled, in respect to maximum
4516             sample rate in each spatial dimension. See <xref linkend="itu-t81"/>,
4517             clause A.1.1. for more details. The <constant>
4518             V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant> control determines how
4519             Cb and Cr components are downsampled after coverting an input image
4520             from RGB to Y'CbCr color space.
4521             </entry>
4522           </row>
4523           <row>
4524             <entrytbl spanname="descr" cols="2">
4525               <tbody valign="top">
4526                 <row>
4527                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_444</constant>
4528                   </entry><entry>No chroma subsampling, each pixel has
4529                   Y, Cr and Cb values.</entry>
4530                 </row>
4531                 <row>
4532                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_422</constant>
4533                   </entry><entry>Horizontally subsample Cr, Cb components
4534                   by a factor of 2.</entry>
4535                 </row>
4536                 <row>
4537                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_420</constant>
4538                   </entry><entry>Subsample Cr, Cb components horizontally
4539                   and vertically by 2.</entry>
4540                 </row>
4541                 <row>
4542                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_411</constant>
4543                   </entry><entry>Horizontally subsample Cr, Cb components
4544                   by a factor of 4.</entry>
4545                 </row>
4546                 <row>
4547                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_410</constant>
4548                   </entry><entry>Subsample Cr, Cb components horizontally
4549                   by 4 and vertically by 2.</entry>
4550                 </row>
4551                 <row>
4552                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY</constant>
4553                   </entry><entry>Use only luminance component.</entry>
4554                 </row>
4555               </tbody>
4556             </entrytbl>
4557           </row>
4558           <row>
4559             <entry spanname="id"><constant>V4L2_CID_JPEG_RESTART_INTERVAL</constant>
4560             </entry><entry>integer</entry>
4561           </row>
4562           <row><entry spanname="descr">
4563               The restart interval determines an interval of inserting RSTm
4564               markers (m = 0..7). The purpose of these markers is to additionally
4565               reinitialize the encoder process, in order to process blocks of
4566               an image independently.
4567               For the lossy compression processes the restart interval unit is
4568               MCU (Minimum Coded Unit) and its value is contained in DRI
4569               (Define Restart Interval) marker. If <constant>
4570               V4L2_CID_JPEG_RESTART_INTERVAL</constant> control is set to 0,
4571               DRI and RSTm markers will not be inserted.
4572             </entry>
4573           </row>
4574           <row id="jpeg-quality-control">
4575             <entry spanname="id"><constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant></entry>
4576             <entry>integer</entry>
4577           </row>
4578           <row>
4579             <entry spanname="descr">
4580               <constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control
4581               determines trade-off between image quality and size.
4582               It provides simpler method for applications to control image quality,
4583               without a need for direct reconfiguration of luminance and chrominance
4584               quantization tables.
4585
4586               In cases where a driver uses quantization tables configured directly
4587               by an application, using interfaces defined elsewhere, <constant>
4588               V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control should be set
4589               by driver to 0.
4590
4591               <para>The value range of this control is driver-specific. Only
4592               positive, non-zero values are meaningful. The recommended range
4593               is 1 - 100, where larger values correspond to better image quality.
4594               </para>
4595             </entry>
4596             </row>
4597           <row id="jpeg-active-marker-control">
4598             <entry spanname="id"><constant>V4L2_CID_JPEG_ACTIVE_MARKER</constant></entry>
4599             <entry>bitmask</entry>
4600           </row>
4601           <row>
4602             <entry spanname="descr">Specify which JPEG markers are included
4603             in compressed stream. This control is valid only for encoders.
4604             </entry>
4605           </row>
4606           <row>
4607             <entrytbl spanname="descr" cols="2">
4608               <tbody valign="top">
4609                 <row>
4610                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP0</constant></entry>
4611                   <entry>Application data segment APP<subscript>0</subscript>.</entry>
4612                 </row><row>
4613                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP1</constant></entry>
4614                   <entry>Application data segment APP<subscript>1</subscript>.</entry>
4615                 </row><row>
4616                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_COM</constant></entry>
4617                   <entry>Comment segment.</entry>
4618                 </row><row>
4619                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DQT</constant></entry>
4620                   <entry>Quantization tables segment.</entry>
4621                 </row><row>
4622                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DHT</constant></entry>
4623                   <entry>Huffman tables segment.</entry>
4624                 </row>
4625               </tbody>
4626             </entrytbl>
4627           </row>
4628           <row><entry></entry></row>
4629         </tbody>
4630       </tgroup>
4631       </table>
4632       <para>For more details about JPEG specification, refer
4633       to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>,
4634       <xref linkend="w3c-jpeg-jfif"/>.</para>
4635     </section>
4636
4637     <section id="image-source-controls">
4638       <title>Image Source Control Reference</title>
4639
4640       <note>
4641         <title>Experimental</title>
4642
4643         <para>This is an <link
4644         linkend="experimental">experimental</link> interface and may
4645         change in the future.</para>
4646       </note>
4647
4648       <para>
4649         The Image Source control class is intended for low-level
4650         control of image source devices such as image sensors. The
4651         devices feature an analogue to digital converter and a bus
4652         transmitter to transmit the image data out of the device.
4653       </para>
4654
4655       <table pgwide="1" frame="none" id="image-source-control-id">
4656       <title>Image Source Control IDs</title>
4657
4658       <tgroup cols="4">
4659         <colspec colname="c1" colwidth="1*" />
4660         <colspec colname="c2" colwidth="6*" />
4661         <colspec colname="c3" colwidth="2*" />
4662         <colspec colname="c4" colwidth="6*" />
4663         <spanspec namest="c1" nameend="c2" spanname="id" />
4664         <spanspec namest="c2" nameend="c4" spanname="descr" />
4665         <thead>
4666           <row>
4667             <entry spanname="id" align="left">ID</entry>
4668             <entry align="left">Type</entry>
4669           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4670           </row>
4671         </thead>
4672         <tbody valign="top">
4673           <row><entry></entry></row>
4674           <row>
4675             <entry spanname="id"><constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant></entry>
4676             <entry>class</entry>
4677           </row>
4678           <row>
4679             <entry spanname="descr">The IMAGE_SOURCE class descriptor.</entry>
4680           </row>
4681           <row>
4682             <entry spanname="id"><constant>V4L2_CID_VBLANK</constant></entry>
4683             <entry>integer</entry>
4684           </row>
4685           <row>
4686             <entry spanname="descr">Vertical blanking. The idle period
4687             after every frame during which no image data is produced.
4688             The unit of vertical blanking is a line. Every line has
4689             length of the image width plus horizontal blanking at the
4690             pixel rate defined by
4691             <constant>V4L2_CID_PIXEL_RATE</constant> control in the
4692             same sub-device.</entry>
4693           </row>
4694           <row>
4695             <entry spanname="id"><constant>V4L2_CID_HBLANK</constant></entry>
4696             <entry>integer</entry>
4697           </row>
4698           <row>
4699             <entry spanname="descr">Horizontal blanking. The idle
4700             period after every line of image data during which no
4701             image data is produced. The unit of horizontal blanking is
4702             pixels.</entry>
4703           </row>
4704           <row>
4705             <entry spanname="id"><constant>V4L2_CID_ANALOGUE_GAIN</constant></entry>
4706             <entry>integer</entry>
4707           </row>
4708           <row>
4709             <entry spanname="descr">Analogue gain is gain affecting
4710             all colour components in the pixel matrix. The gain
4711             operation is performed in the analogue domain before A/D
4712             conversion.
4713             </entry>
4714           </row>
4715           <row><entry></entry></row>
4716         </tbody>
4717       </tgroup>
4718       </table>
4719
4720     </section>
4721
4722     <section id="image-process-controls">
4723       <title>Image Process Control Reference</title>
4724
4725       <note>
4726         <title>Experimental</title>
4727
4728         <para>This is an <link
4729         linkend="experimental">experimental</link> interface and may
4730         change in the future.</para>
4731       </note>
4732
4733       <para>
4734         The Image Source control class is intended for low-level control of
4735         image processing functions. Unlike
4736         <constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant>, the controls in
4737         this class affect processing the image, and do not control capturing
4738         of it.
4739       </para>
4740
4741       <table pgwide="1" frame="none" id="image-process-control-id">
4742       <title>Image Source Control IDs</title>
4743
4744       <tgroup cols="4">
4745         <colspec colname="c1" colwidth="1*" />
4746         <colspec colname="c2" colwidth="6*" />
4747         <colspec colname="c3" colwidth="2*" />
4748         <colspec colname="c4" colwidth="6*" />
4749         <spanspec namest="c1" nameend="c2" spanname="id" />
4750         <spanspec namest="c2" nameend="c4" spanname="descr" />
4751         <thead>
4752           <row>
4753             <entry spanname="id" align="left">ID</entry>
4754             <entry align="left">Type</entry>
4755           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4756           </row>
4757         </thead>
4758         <tbody valign="top">
4759           <row><entry></entry></row>
4760           <row>
4761             <entry spanname="id"><constant>V4L2_CID_IMAGE_PROC_CLASS</constant></entry>
4762             <entry>class</entry>
4763           </row>
4764           <row>
4765             <entry spanname="descr">The IMAGE_PROC class descriptor.</entry>
4766           </row>
4767           <row>
4768             <entry spanname="id"><constant>V4L2_CID_LINK_FREQ</constant></entry>
4769             <entry>integer menu</entry>
4770           </row>
4771           <row>
4772             <entry spanname="descr">Data bus frequency. Together with the
4773             media bus pixel code, bus type (clock cycles per sample), the
4774             data bus frequency defines the pixel rate
4775             (<constant>V4L2_CID_PIXEL_RATE</constant>) in the
4776             pixel array (or possibly elsewhere, if the device is not an
4777             image sensor). The frame rate can be calculated from the pixel
4778             clock, image width and height and horizontal and vertical
4779             blanking. While the pixel rate control may be defined elsewhere
4780             than in the subdev containing the pixel array, the frame rate
4781             cannot be obtained from that information. This is because only
4782             on the pixel array it can be assumed that the vertical and
4783             horizontal blanking information is exact: no other blanking is
4784             allowed in the pixel array. The selection of frame rate is
4785             performed by selecting the desired horizontal and vertical
4786             blanking. The unit of this control is Hz. </entry>
4787           </row>
4788           <row>
4789             <entry spanname="id"><constant>V4L2_CID_PIXEL_RATE</constant></entry>
4790             <entry>64-bit integer</entry>
4791           </row>
4792           <row>
4793             <entry spanname="descr">Pixel rate in the source pads of
4794             the subdev. This control is read-only and its unit is
4795             pixels / second.
4796             </entry>
4797           </row>
4798           <row>
4799             <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN</constant></entry>
4800             <entry>menu</entry>
4801           </row>
4802           <row id="v4l2-test-pattern">
4803             <entry spanname="descr"> Some capture/display/sensor devices have
4804             the capability to generate test pattern images. These hardware
4805             specific test patterns can be used to test if a device is working
4806             properly.</entry>
4807           </row>
4808           <row><entry></entry></row>
4809         </tbody>
4810       </tgroup>
4811       </table>
4812
4813     </section>
4814
4815     <section id="dv-controls">
4816       <title>Digital Video Control Reference</title>
4817
4818       <note>
4819         <title>Experimental</title>
4820
4821         <para>This is an <link
4822         linkend="experimental">experimental</link> interface and may
4823         change in the future.</para>
4824       </note>
4825
4826       <para>
4827         The Digital Video control class is intended to control receivers
4828         and transmitters for <ulink url="http://en.wikipedia.org/wiki/Vga">VGA</ulink>,
4829         <ulink url="http://en.wikipedia.org/wiki/Digital_Visual_Interface">DVI</ulink>
4830         (Digital Visual Interface), HDMI (<xref linkend="hdmi" />) and DisplayPort (<xref linkend="dp" />).
4831         These controls are generally expected to be private to the receiver or transmitter
4832         subdevice that implements them, so they are only exposed on the
4833         <filename>/dev/v4l-subdev*</filename> device node.
4834       </para>
4835
4836       <para>Note that these devices can have multiple input or output pads which are
4837       hooked up to e.g. HDMI connectors. Even though the subdevice will receive or
4838       transmit video from/to only one of those pads, the other pads can still be
4839       active when it comes to EDID (Extended Display Identification Data,
4840       <xref linkend="vesaedid" />) and HDCP (High-bandwidth Digital Content
4841       Protection System, <xref linkend="hdcp" />) processing, allowing the device
4842       to do the fairly slow EDID/HDCP handling in advance. This allows for quick
4843       switching between connectors.</para>
4844
4845       <para>These pads appear in several of the controls in this section as
4846       bitmasks, one bit for each pad. Bit 0 corresponds to pad 0, bit 1 to pad 1,
4847       etc. The maximum value of the control is the set of valid pads.</para>
4848
4849       <table pgwide="1" frame="none" id="dv-control-id">
4850       <title>Digital Video Control IDs</title>
4851
4852       <tgroup cols="4">
4853         <colspec colname="c1" colwidth="1*" />
4854         <colspec colname="c2" colwidth="6*" />
4855         <colspec colname="c3" colwidth="2*" />
4856         <colspec colname="c4" colwidth="6*" />
4857         <spanspec namest="c1" nameend="c2" spanname="id" />
4858         <spanspec namest="c2" nameend="c4" spanname="descr" />
4859         <thead>
4860           <row>
4861             <entry spanname="id" align="left">ID</entry>
4862             <entry align="left">Type</entry>
4863           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4864           </row>
4865         </thead>
4866         <tbody valign="top">
4867           <row><entry></entry></row>
4868           <row>
4869             <entry spanname="id"><constant>V4L2_CID_DV_CLASS</constant></entry>
4870             <entry>class</entry>
4871           </row>
4872           <row>
4873             <entry spanname="descr">The Digital Video class descriptor.</entry>
4874           </row>
4875           <row>
4876             <entry spanname="id"><constant>V4L2_CID_DV_TX_HOTPLUG</constant></entry>
4877             <entry>bitmask</entry>
4878           </row>
4879           <row>
4880             <entry spanname="descr">Many connectors have a hotplug pin which is high
4881             if EDID information is available from the source. This control shows the
4882             state of the hotplug pin as seen by the transmitter.
4883             Each bit corresponds to an output pad on the transmitter. If an output pad
4884             does not have an associated hotplug pin, then the bit for that pad will be 0.
4885             This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors.
4886             </entry>
4887           </row>
4888           <row>
4889             <entry spanname="id"><constant>V4L2_CID_DV_TX_RXSENSE</constant></entry>
4890             <entry>bitmask</entry>
4891           </row>
4892           <row>
4893             <entry spanname="descr">Rx Sense is the detection of pull-ups on the TMDS
4894             clock lines. This normally means that the sink has left/entered standby (i.e.
4895             the transmitter can sense that the receiver is ready to receive video).
4896             Each bit corresponds to an output pad on the transmitter. If an output pad
4897             does not have an associated Rx Sense, then the bit for that pad will be 0.
4898             This read-only control is applicable to DVI-D and HDMI devices.
4899             </entry>
4900           </row>
4901           <row>
4902             <entry spanname="id"><constant>V4L2_CID_DV_TX_EDID_PRESENT</constant></entry>
4903             <entry>bitmask</entry>
4904           </row>
4905           <row>
4906             <entry spanname="descr">When the transmitter sees the hotplug signal from the
4907             receiver it will attempt to read the EDID. If set, then the transmitter has read
4908             at least the first block (= 128 bytes).
4909             Each bit corresponds to an output pad on the transmitter. If an output pad
4910             does not support EDIDs, then the bit for that pad will be 0.
4911             This read-only control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors.
4912             </entry>
4913           </row>
4914           <row>
4915             <entry spanname="id"><constant>V4L2_CID_DV_TX_MODE</constant></entry>
4916             <entry id="v4l2-dv-tx-mode">enum v4l2_dv_tx_mode</entry>
4917           </row>
4918           <row>
4919             <entry spanname="descr">HDMI transmitters can transmit in DVI-D mode (just video)
4920             or in HDMI mode (video + audio + auxiliary data). This control selects which mode
4921             to use: V4L2_DV_TX_MODE_DVI_D or V4L2_DV_TX_MODE_HDMI.
4922             This control is applicable to HDMI connectors.
4923             </entry>
4924           </row>
4925           <row>
4926             <entry spanname="id"><constant>V4L2_CID_DV_TX_RGB_RANGE</constant></entry>
4927             <entry id="v4l2-dv-rgb-range">enum v4l2_dv_rgb_range</entry>
4928           </row>
4929           <row>
4930             <entry spanname="descr">Select the quantization range for RGB output. V4L2_DV_RANGE_AUTO
4931             follows the RGB quantization range specified in the standard for the video interface
4932             (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard
4933             to be compatible with sinks that have not implemented the standard correctly
4934             (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be
4935             used whereas limited range sets the range to (16 &lt;&lt; (N-8)) - (235 &lt;&lt; (N-8))
4936             where N is the number of bits per component.
4937             This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors.
4938             </entry>
4939           </row>
4940           <row>
4941             <entry spanname="id"><constant>V4L2_CID_DV_RX_POWER_PRESENT</constant></entry>
4942             <entry>bitmask</entry>
4943           </row>
4944           <row>
4945             <entry spanname="descr">Detects whether the receiver receives power from the source
4946             (e.g. HDMI carries 5V on one of the pins). This is often used to power an eeprom
4947             which contains EDID information, such that the source can read the EDID even if
4948             the sink is in standby/power off.
4949             Each bit corresponds to an input pad on the transmitter. If an input pad
4950             cannot detect whether power is present, then the bit for that pad will be 0.
4951             This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors.
4952             </entry>
4953           </row>
4954           <row>
4955             <entry spanname="id"><constant>V4L2_CID_DV_RX_RGB_RANGE</constant></entry>
4956             <entry>enum v4l2_dv_rgb_range</entry>
4957           </row>
4958           <row>
4959             <entry spanname="descr">Select the quantization range for RGB input. V4L2_DV_RANGE_AUTO
4960             follows the RGB quantization range specified in the standard for the video interface
4961             (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard
4962             to be compatible with sources that have not implemented the standard correctly
4963             (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be
4964             used whereas limited range sets the range to (16 &lt;&lt; (N-8)) - (235 &lt;&lt; (N-8))
4965             where N is the number of bits per component.
4966             This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors.
4967             </entry>
4968           </row>
4969           <row><entry></entry></row>
4970         </tbody>
4971       </tgroup>
4972       </table>
4973
4974     </section>
4975
4976     <section id="fm-rx-controls">
4977       <title>FM Receiver Control Reference</title>
4978
4979       <para>The FM Receiver (FM_RX) class includes controls for common features of
4980       FM Reception capable devices.</para>
4981
4982       <table pgwide="1" frame="none" id="fm-rx-control-id">
4983       <title>FM_RX Control IDs</title>
4984
4985       <tgroup cols="4">
4986         <colspec colname="c1" colwidth="1*" />
4987         <colspec colname="c2" colwidth="6*" />
4988         <colspec colname="c3" colwidth="2*" />
4989         <colspec colname="c4" colwidth="6*" />
4990         <spanspec namest="c1" nameend="c2" spanname="id" />
4991         <spanspec namest="c2" nameend="c4" spanname="descr" />
4992         <thead>
4993           <row>
4994             <entry spanname="id" align="left">ID</entry>
4995             <entry align="left">Type</entry>
4996           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4997           </row>
4998         </thead>
4999         <tbody valign="top">
5000           <row><entry></entry></row>
5001           <row>
5002             <entry spanname="id"><constant>V4L2_CID_FM_RX_CLASS</constant>&nbsp;</entry>
5003             <entry>class</entry>
5004           </row><row><entry spanname="descr">The FM_RX class
5005 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
5006 description of this control class.</entry>
5007           </row>
5008           <row>
5009             <entry spanname="id"><constant>V4L2_CID_RDS_RECEPTION</constant>&nbsp;</entry>
5010             <entry>boolean</entry>
5011           </row><row><entry spanname="descr">Enables/disables RDS
5012           reception by the radio tuner</entry>
5013           </row>
5014           <row>
5015             <entry spanname="id"><constant>V4L2_CID_TUNE_DEEMPHASIS</constant>&nbsp;</entry>
5016             <entry>enum v4l2_deemphasis</entry>
5017           </row>
5018           <row id="v4l2-deemphasis"><entry spanname="descr">Configures the de-emphasis value for reception.
5019 A de-emphasis filter is applied to the broadcast to accentuate the high audio frequencies.
5020 Depending on the region, a time constant of either 50 or 75 useconds is used. The enum&nbsp;v4l2_deemphasis
5021 defines possible values for de-emphasis. Here they are:</entry>
5022         </row><row>
5023         <entrytbl spanname="descr" cols="2">
5024                   <tbody valign="top">
5025                     <row>
5026                       <entry><constant>V4L2_DEEMPHASIS_DISABLED</constant>&nbsp;</entry>
5027                       <entry>No de-emphasis is applied.</entry>
5028                     </row>
5029                     <row>
5030                       <entry><constant>V4L2_DEEMPHASIS_50_uS</constant>&nbsp;</entry>
5031                       <entry>A de-emphasis of 50 uS is used.</entry>
5032                     </row>
5033                     <row>
5034                       <entry><constant>V4L2_DEEMPHASIS_75_uS</constant>&nbsp;</entry>
5035                       <entry>A de-emphasis of 75 uS is used.</entry>
5036                     </row>
5037                   </tbody>
5038                 </entrytbl>
5039
5040           </row>
5041           <row><entry></entry></row>
5042         </tbody>
5043       </tgroup>
5044       </table>
5045
5046       </section>
5047
5048     <section id="rf-tuner-controls">
5049       <title>RF Tuner Control Reference</title>
5050
5051       <para>
5052 The RF Tuner (RF_TUNER) class includes controls for common features of devices
5053 having RF tuner.
5054       </para>
5055       <para>
5056 In this context, RF tuner is radio receiver circuit between antenna and
5057 demodulator. It receives radio frequency (RF) from the antenna and converts that
5058 received signal to lower intermediate frequency (IF) or baseband frequency (BB).
5059 Tuners that could do baseband output are often called Zero-IF tuners. Older
5060 tuners were typically simple PLL tuners inside a metal box, whilst newer ones
5061 are highly integrated chips without a metal box "silicon tuners". These controls
5062 are mostly applicable for new feature rich silicon tuners, just because older
5063 tuners does not have much adjustable features.
5064       </para>
5065       <para>
5066 For more information about RF tuners see
5067 <ulink url="http://en.wikipedia.org/wiki/Tuner_%28radio%29">Tuner (radio)</ulink>
5068 and
5069 <ulink url="http://en.wikipedia.org/wiki/RF_front_end">RF front end</ulink>
5070 from Wikipedia.
5071       </para>
5072
5073       <table pgwide="1" frame="none" id="rf-tuner-control-id">
5074         <title>RF_TUNER Control IDs</title>
5075
5076         <tgroup cols="4">
5077           <colspec colname="c1" colwidth="1*" />
5078           <colspec colname="c2" colwidth="6*" />
5079           <colspec colname="c3" colwidth="2*" />
5080           <colspec colname="c4" colwidth="6*" />
5081           <spanspec namest="c1" nameend="c2" spanname="id" />
5082           <spanspec namest="c2" nameend="c4" spanname="descr" />
5083           <thead>
5084             <row>
5085               <entry spanname="id" align="left">ID</entry>
5086               <entry align="left">Type</entry>
5087             </row>
5088             <row rowsep="1">
5089               <entry spanname="descr" align="left">Description</entry>
5090             </row>
5091           </thead>
5092           <tbody valign="top">
5093             <row><entry></entry></row>
5094             <row>
5095               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_CLASS</constant>&nbsp;</entry>
5096               <entry>class</entry>
5097             </row><row><entry spanname="descr">The RF_TUNER class
5098 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
5099 description of this control class.</entry>
5100             </row>
5101             <row>
5102               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH_AUTO</constant>&nbsp;</entry>
5103               <entry>boolean</entry>
5104             </row>
5105             <row>
5106               <entry spanname="descr">Enables/disables tuner radio channel
5107 bandwidth configuration. In automatic mode bandwidth configuration is performed
5108 by the driver.</entry>
5109             </row>
5110             <row>
5111               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH</constant>&nbsp;</entry>
5112               <entry>integer</entry>
5113             </row>
5114             <row>
5115               <entry spanname="descr">Filter(s) on tuner signal path are used to
5116 filter signal according to receiving party needs. Driver configures filters to
5117 fulfill desired bandwidth requirement. Used when V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not
5118 set. Unit is in Hz. The range and step are driver-specific.</entry>
5119             </row>
5120             <row>
5121               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant>&nbsp;</entry>
5122               <entry>boolean</entry>
5123             </row>
5124             <row>
5125               <entry spanname="descr">Enables/disables LNA automatic gain control (AGC)</entry>
5126             </row>
5127             <row>
5128               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant>&nbsp;</entry>
5129               <entry>boolean</entry>
5130             </row>
5131             <row>
5132               <entry spanname="descr">Enables/disables mixer automatic gain control (AGC)</entry>
5133             </row>
5134             <row>
5135               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant>&nbsp;</entry>
5136               <entry>boolean</entry>
5137             </row>
5138             <row>
5139               <entry spanname="descr">Enables/disables IF automatic gain control (AGC)</entry>
5140             </row>
5141             <row>
5142               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN</constant>&nbsp;</entry>
5143               <entry>integer</entry>
5144             </row>
5145             <row>
5146               <entry spanname="descr">LNA (low noise amplifier) gain is first
5147 gain stage on the RF tuner signal path. It is located very close to tuner
5148 antenna input. Used when <constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> is not set.
5149 The range and step are driver-specific.</entry>
5150             </row>
5151             <row>
5152               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN</constant>&nbsp;</entry>
5153               <entry>integer</entry>
5154             </row>
5155             <row>
5156               <entry spanname="descr">Mixer gain is second gain stage on the RF
5157 tuner signal path. It is located inside mixer block, where RF signal is
5158 down-converted by the mixer. Used when <constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant>
5159 is not set. The range and step are driver-specific.</entry>
5160             </row>
5161             <row>
5162               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN</constant>&nbsp;</entry>
5163               <entry>integer</entry>
5164             </row>
5165             <row>
5166               <entry spanname="descr">IF gain is last gain stage on the RF tuner
5167 signal path. It is located on output of RF tuner. It controls signal level of
5168 intermediate frequency output or baseband output. Used when
5169 <constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> is not set. The range and step are
5170 driver-specific.</entry>
5171             </row>
5172             <row>
5173               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_PLL_LOCK</constant>&nbsp;</entry>
5174               <entry>boolean</entry>
5175             </row>
5176             <row>
5177               <entry spanname="descr">Is synthesizer PLL locked? RF tuner is
5178 receiving given frequency when that control is set. This is a read-only control.
5179 </entry>
5180             </row>
5181           </tbody>
5182         </tgroup>
5183       </table>
5184     </section>
5185 </section>