[FFmpeg-devel] [PATCH v2] avformat/vpcc: fix VP9 metadata in FLV and RTMP

[James Almer]

On 9/3/2023 1:00 PM, Alessandro Ros wrote:
> I integrated James A. comment and fixed patch format.

I think you forgot to git add.

> 
> In order to send VP9 tracks with FLV or RTMP, the enhanced RTMP
> specification tells that VPCodecConfigurationRecord, a.k.a. vpcC
> ISO-BMFF box, must be inserted into a metadata message. However, the
> function responsible for generating vpcCs currently returns invalid
> boxes, that are lacking the Version and Flag fields, inherited from
> FullBox. For some reason, both flags were being added manually in
> movenc. This patch fixes the issue.
> 
> Signed-off-by: Alessandro Ros <aler9.dev at gmail.com>
> ---
>   libavformat/movenc.c | 3 ---
>   libavformat/vpcc.c   | 2 ++
>   2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/libavformat/movenc.c b/libavformat/movenc.c
> index 7ef6cef46a..696ae5a6c9 100644
> --- a/libavformat/movenc.c
> +++ b/libavformat/movenc.c
> @@ -1441,10 +1441,7 @@ static int mov_write_vpcc_tag(AVFormatContext *s, AVIOContext *pb, MOVTrack *tra
>   
>       avio_wb32(pb, 0);
>       ffio_wfourcc(pb, "vpcC");
> -    avio_w8(pb, 1); /* version */
> -    avio_wb24(pb, 0); /* flags */
>       ff_isom_write_vpcc(s, pb, track->vos_data, track->vos_len, track->par);
> -
>       return update_size(pb, pos);
>   }
>   
> diff --git a/libavformat/vpcc.c b/libavformat/vpcc.c
> index ea66959abf..256407dd6d 100644
> --- a/libavformat/vpcc.c
> +++ b/libavformat/vpcc.c
> @@ -208,6 +208,8 @@ int ff_isom_write_vpcc(AVFormatContext *s, AVIOContext *pb,
>       if (ret < 0)
>           return ret;
>   
> +    avio_w8(pb, 1); /* version */
> +    avio_wb24(pb, 0); /* flags */
>       avio_w8(pb, vpcc.profile);
>       avio_w8(pb, vpcc.level);
>       avio_w8(pb, (vpcc.bitdepth << 4) | (vpcc.chroma_subsampling << 1) | vpcc.full_range_flag);