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    SubjectRe: [PATCH v1 02/24] media: doc: Document dual use of H.264 pic_num/frame_num
    On 28.03.2022 15:59, Nicolas Dufresne wrote:
    >These two fields needs documentation as they have dual meaning. It is also

    s/needs/need/

    >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

    s/developpers/developers/
    (seems to be a common typo among native French speakers ;))

    >would suggest to remove pic_num entirely.

    I think that suggestion should be placed as a FIXME/TODO comment into the
    source code as it is way easier to find for future developers creating a V2.

    >
    >Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
    Reviewed-by: Sebastian Fricke <sebastian.fricke@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

    Minor suggestion, for short term you use singular (reference) and for
    long term you use plural (references), I would stick to one of both.
    (Below you only use plural so maybe stick to plural here as well)

    >+ 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.

    s/describes/described/

    Greetings,
    Sebastian

    > * - __u8
    > - ``fields``
    > - Specifies how the DPB entry is referenced. See :ref:`Reference Fields <h264_ref_fields>`
    >--
    >2.34.1
    >

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