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    Subject[PATCH v1 02/24] media: doc: Document dual use of H.264 pic_num/frame_num
    Date
    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@collabora.com>
    ---
    .../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
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