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authorStanimir Varbanov <stanimir.varbanov@linaro.org>2021-06-22 14:39:57 +0300
committerMauro Carvalho Chehab <mchehab+huawei@kernel.org>2021-08-04 15:43:52 +0300
commit9d5adeecc409365e45cd89657f0392d0dd5c217f (patch)
tree44ea50bac165972df216dcf0674463bb97cb6727 /Documentation/userspace-api
parentea9f91199ca99dd9b3fba004b7614eed233ba1ac (diff)
downloadlinux-9d5adeecc409365e45cd89657f0392d0dd5c217f.tar.xz
media: v4l2-ctrls: Add intra-refresh period control
Add a control to set intra-refresh period. Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Diffstat (limited to 'Documentation/userspace-api')
-rw-r--r--Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst17
1 files changed, 16 insertions, 1 deletions
diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
index 999b2360cef8..976d34445a24 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
@@ -1175,9 +1175,24 @@ enum v4l2_mpeg_video_h264_entropy_mode -
macroblocks refreshed every frame. Each frame a successive set of
macroblocks is refreshed until the cycle completes and starts from
the top of the frame. Setting this control to zero means that
- macroblocks will not be refreshed.
+ macroblocks will not be refreshed. Note that this control will not
+ take effect when ``V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD`` control
+ is set to non zero value.
Applicable to H264, H263 and MPEG4 encoder.
+``V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD (integer)``
+ Intra macroblock refresh period. This sets the period to refresh
+ the whole frame. In other words, this defines the number of frames
+ for which the whole frame will be intra-refreshed. An example:
+ setting period to 1 means that the whole frame will be refreshed,
+ setting period to 2 means that the half of macroblocks will be
+ intra-refreshed on frameX and the other half of macroblocks
+ will be refreshed in frameX + 1 and so on. Setting the period to
+ zero means no period is specified.
+ Note that if the client sets this control to non zero value the
+ ``V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB`` control shall be
+ ignored. Applicable to H264 and HEVC encoders.
+
``V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE (boolean)``
Frame level rate control enable. If this control is disabled then
the quantization parameter for each frame type is constant and set