[FFmpeg-devel] [PATCH 30/39] avcodec/internal: Remove outdated documentation of ff_alloc_packet2()

[James Almer]

On 5/21/2021 6:17 AM, Andreas Rheinhardt wrote:
> Its documentation described the way user-supplied buffers worked
> before 93016f5d1d280f9cb7856883af287fa66affc04c.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>   libavcodec/internal.h | 16 ++++++----------
>   1 file changed, 6 insertions(+), 10 deletions(-)
> 
> diff --git a/libavcodec/internal.h b/libavcodec/internal.h
> index 60f65d3f2c..19c4e9e3f4 100644
> --- a/libavcodec/internal.h
> +++ b/libavcodec/internal.h
> @@ -229,20 +229,16 @@ void ff_color_frame(AVFrame *frame, const int color[4]);
>   #define FF_MAX_EXTRADATA_SIZE ((1 << 28) - AV_INPUT_BUFFER_PADDING_SIZE)
>   
>   /**
> - * Check AVPacket size and/or allocate data.
> + * Check AVPacket size and allocate data.
>    *
>    * Encoders supporting AVCodec.encode2() can use this as a convenience to
> - * ensure the output packet data is large enough, whether provided by the user
> - * or allocated in this function.
> + * obtain a big enough buffer for the encoded bitstream.
>    *
>    * @param avctx   the AVCodecContext of the encoder
> - * @param avpkt   the AVPacket
> - *                If avpkt->data is already set, avpkt->size is checked
> - *                to ensure it is large enough.
> - *                If avpkt->data is NULL, a new buffer is allocated.
> - *                avpkt->size is set to the specified size.
> - *                All other AVPacket fields will be reset with av_init_packet().
> - * @param size    the minimum required packet size
> + * @param avpkt   The AVPacket: on success, avpkt->data will point to a buffer
> + *                of size at least `size`; avpkt->buf may be `NULL`.

May? You're no longer calling av_new_packet() in any scenario. IMO 
better be explicit that the resulting packet will not be refcounted.

> + *                This packet must be initially blank.
> + * @param size    an upper bound of the size of the packet to encode
>    * @param min_size This is a hint to the allocation algorithm, which indicates
>    *                to what minimal size the caller might later shrink the packet
>    *                to. Encoders often allocate packets which are larger than the

LGTM otherwise.