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Diffstat (limited to 'Documentation/video4linux/vivid.txt')
| -rw-r--r-- | Documentation/video4linux/vivid.txt | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/Documentation/video4linux/vivid.txt b/Documentation/video4linux/vivid.txt index cd4b5a1ac529..e35d376b7f64 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. @@ -888,7 +895,7 @@ Section 10.1: Video and Sliced VBI looping The way to enable video/VBI looping is currently fairly crude. A 'Loop Video' control is available in the "Vivid" control class of the video -output and VBI output devices. When checked the video looping will be enabled. +capture and VBI capture devices. When checked the video looping will be enabled. Once enabled any video S-Video or HDMI input will show a static test pattern until the video output has started. At that time the video output will be looped to the video input provided that: @@ -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. |