These two fields needs documentation as they have dual meaning. It is also confusing since pic_num is a derived value from frame_num, so this should help application developpers. If we ever need to make a V2 of this API, I would suggest to remove pic_num entirely. Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx> --- .../media/v4l/ext-ctrls-codec-stateless.rst | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst index 6541e4c32b26..f634f20bcfbe 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst @@ -649,10 +649,16 @@ Stateless Codec Control ID :c:type:`timeval` in struct :c:type:`v4l2_buffer` to a __u64. * - __u32 - ``pic_num`` - - + - For short term reference, this should match the derived value PicNum + (8-28) and for long term references it should match the derived value + LongTermPicNum (8-29). Note that pic_num is the same as FrameNumWrap + for frame decoding. * - __u16 - ``frame_num`` - - + - For short term references, this should match the frame_num value from + the slice header syntax (the driver will wrap the value if neeeded). For + long term references, this should be set to the value of + long_term_frame_idx describes in the dec_ref_pic_marking() syntax. * - __u8 - ``fields`` - Specifies how the DPB entry is referenced. See :ref:`Reference Fields <h264_ref_fields>` -- 2.34.1