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| author | Dikshita Agarwal <dikshita@codeaurora.org> | 2021-03-24 10:54:31 +0100 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2021-04-06 14:49:02 +0200 |
| commit | f15c54cf3f684cd1a65f6ebc55ee9ada533ec6ef (patch) | |
| tree | 3a7ad41341926b9c5d42a7c3ba3bb1ad52f6ece9 /Documentation/userspace-api | |
| parent | media: venus: core: Drop second v4l2 device unregister (diff) | |
| download | linux-f15c54cf3f684cd1a65f6ebc55ee9ada533ec6ef.tar.xz linux-f15c54cf3f684cd1a65f6ebc55ee9ada533ec6ef.zip | |
media: v4l2-ctrl: add controls for long term reference.
Long Term Reference (LTR) frames are the frames that are encoded
sometime in the past and stored in the DPB buffer list to be used
as reference to encode future frames.
This change adds controls to enable this feature.
Signed-off-by: Dikshita Agarwal <dikshita@codeaurora.org>
Reviewed-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 | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst index 188aef8e40d0..6af3774fbb75 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst @@ -3427,3 +3427,21 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - so this has to come from client. This is applicable to H264 and valid Range is from 0 to 63. Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1. + +``V4L2_CID_MPEG_VIDEO_LTR_COUNT (integer)`` + Specifies the maximum number of Long Term Reference (LTR) frames at any + given time that the encoder can keep. + This is applicable to the H264 and HEVC encoders. + +``V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX (integer)`` + After setting this control the frame that will be queued next + will be marked as a Long Term Reference (LTR) frame + and given this LTR index which ranges from 0 to LTR_COUNT-1. + This is applicable to the H264 and HEVC encoders. + Source Rec. ITU-T H.264 (06/2019); Table 7.9 + +``V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES (bitmask)`` + Specifies the Long Term Reference (LTR) frame(s) to be used for + encoding the next frame queued after setting this control. + This provides a bitmask which consists of bits [0, LTR_COUNT-1]. + This is applicable to the H264 and HEVC encoders. |