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| author | Stanimir Varbanov <stanimir.varbanov@linaro.org> | 2021-06-22 13:39:57 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2021-08-04 14:43:52 +0200 |
| commit | 9d5adeecc409365e45cd89657f0392d0dd5c217f (patch) | |
| tree | 44ea50bac165972df216dcf0674463bb97cb6727 /Documentation/userspace-api | |
| parent | ea9f91199ca99dd9b3fba004b7614eed233ba1ac (diff) | |
| download | lwn-9d5adeecc409365e45cd89657f0392d0dd5c217f.tar.gz lwn-9d5adeecc409365e45cd89657f0392d0dd5c217f.zip | |
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.rst | 17 |
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 |