From 64d5702229d86deacf42a43bc893a981f72d4908 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sun, 31 May 2015 08:10:32 -0300 Subject: [PATCH] [media] vivid.txt: update the vivid documentation Document the new Transfer Function control (and fix the documentation for the other colorspace controls which were not quite correct). Mention the support for 4:2:0 and more multiplanar formats. Update the TODO list at the end. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/vivid.txt | 30 +++++++++++++++++------------ 1 file changed, 18 insertions(+), 12 deletions(-) diff --git a/Documentation/video4linux/vivid.txt b/Documentation/video4linux/vivid.txt index cd4b5a1ac529..0c1b3a6ba6be 100644 --- a/Documentation/video4linux/vivid.txt +++ b/Documentation/video4linux/vivid.txt @@ -631,26 +631,33 @@ Timestamp Source: selects when the timestamp for each buffer is taken. Colorspace: selects which colorspace should be used when generating the image. This only applies if the CSC Colorbar test pattern is selected, - otherwise the test pattern will go through unconverted (except for - the so-called 'Transfer Function' corrections and the R'G'B' to Y'CbCr - conversion). This behavior is also what you want, since a 75% Colorbar + otherwise the test pattern will go through unconverted. + This behavior is also what you want, since a 75% Colorbar should really have 75% signal intensity and should not be affected by colorspace conversions. Changing the colorspace will result in the V4L2_EVENT_SOURCE_CHANGE to be sent since it emulates a detected colorspace change. +Transfer Function: selects which colorspace transfer function should be used when + generating an image. This only applies if the CSC Colorbar test pattern is + selected, otherwise the test pattern will go through unconverted. + This behavior is also what you want, since a 75% Colorbar + should really have 75% signal intensity and should not be affected + by colorspace conversions. + + Changing the transfer function will result in the V4L2_EVENT_SOURCE_CHANGE + to be sent since it emulates a detected colorspace change. + Y'CbCr Encoding: selects which Y'CbCr encoding should be used when generating - a Y'CbCr image. This only applies if the CSC Colorbar test pattern is - selected, and if the format is set to a Y'CbCr format as opposed to an - RGB format. + a Y'CbCr image. This only applies if the format is set to a Y'CbCr format + as opposed to an RGB format. Changing the Y'CbCr encoding will result in the V4L2_EVENT_SOURCE_CHANGE to be sent since it emulates a detected colorspace change. Quantization: selects which quantization should be used for the RGB or Y'CbCr - encoding when generating the test pattern. This only applies if the CSC - Colorbar test pattern is selected. + encoding when generating the test pattern. Changing the quantization will result in the V4L2_EVENT_SOURCE_CHANGE to be sent since it emulates a detected colorspace change. @@ -985,8 +992,9 @@ to change crop and compose rectangles on the fly. Section 12: Formats ------------------- -The driver supports all the regular packed YUYV formats, 16, 24 and 32 RGB -packed formats and two multiplanar formats (one luma and one chroma plane). +The driver supports all the regular packed and planar 4:4:4, 4:2:2 and 4:2:0 +YUYV formats, 8, 16, 24 and 32 RGB packed formats and various multiplanar +formats. The alpha component can be set through the 'Alpha Component' User control for those formats that support it. If the 'Apply Alpha To Red Only' control @@ -1119,11 +1127,9 @@ Just as a reminder and in no particular order: - Use per-queue locks and/or per-device locks to improve throughput - Add support to loop from a specific output to a specific input across vivid instances -- Add support for VIDIOC_EXPBUF once support for that has been added to vb2 - The SDR radio should use the same 'frequencies' for stations as the normal radio receiver, and give back noise if the frequency doesn't match up with a station frequency -- Improve the sine generation of the SDR radio. - Make a thread for the RDS generation, that would help in particular for the "Controls" RDS Rx I/O Mode as the read-only RDS controls could be updated in real-time. -- 2.39.2