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authorHans Verkuil <hans.verkuil@cisco.com>2015-05-31 14:10:32 +0300
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-06-05 17:52:12 +0300
commit64d5702229d86deacf42a43bc893a981f72d4908 (patch)
tree4485295fdcc45bbb8a325141dacb67ce4965bad4 /Documentation/video4linux
parente1dedcfff1bbaa6b56a40116ee402b6d222e20c9 (diff)
downloadlinux-64d5702229d86deacf42a43bc893a981f72d4908.tar.xz
[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 <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'Documentation/video4linux')
-rw-r--r--Documentation/video4linux/vivid.txt30
1 files 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.