[FFmpeg-devel] [PATCH] avformat/hlsenc: add reference stream index for split segment

[Jeyapal, Karthick]

On 2/27/18 11:09 AM, Steven Liu wrote:
> fix ticket: #7044
> Get the first video stream to reference for split segment
> when there have more than one video stream
>
> Signed-off-by: Steven Liu <lq at chinaffmpeg.org>
> ---
>  libavformat/hlsenc.c | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
> index ff064732a1..8567227885 100644
> --- a/libavformat/hlsenc.c
> +++ b/libavformat/hlsenc.c
> @@ -129,6 +129,7 @@ typedef struct VariantStream {
>      int nb_entries;
>      int discontinuity_set;
>      int discontinuity;
> +    int reference_stream_index;
>  
>      HLSSegment *segments;
>      HLSSegment *last_segment;
> @@ -2155,8 +2156,10 @@ static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
>                                         * st->time_base.num / st->time_base.den;
>              vs->dpp = (double)(pkt->duration) * st->time_base.num / st->time_base.den;
>          } else {
> -            if (pkt->duration) {
> -                vs->duration += (double)(pkt->duration) * st->time_base.num / st->time_base.den;
> +           if (pkt->duration) {
> +                if (pkt->stream_index == vs->reference_stream_index) {
> +                    vs->duration += (double)(pkt->duration) * st->time_base.num / st->time_base.den;
> +                }
Still the duration variable in other places is being set for all video streams. 
Maybe it is better to restrict the “is_ref_pkt” to 1, only for vs->reference_stream_index.
>              } else {
>                  av_log(s, AV_LOG_WARNING, "pkt->duration = 0, maybe the hls segment duration will not precise\n");
>                  vs->duration = (double)(pkt->pts - vs->end_pts) * st->time_base.num / st->time_base.den;
> @@ -2497,6 +2500,11 @@ static int hls_init(AVFormatContext *s)
>  
>          for (j = 0; j < vs->nb_streams; j++) {
>              vs->has_video += vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO;
> +            /* Get one video stream to reference for split segments
> +             * so use the first video stream index. */
> +            if (vs->has_video == 1) {
> +                vs->reference_stream_index = j;
> +            }
This doesn’t look correct. Potentially vs->reference_stream_index could get overwritten by audio and/or subtitle stream index.
>              vs->has_subtitle += vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE;
>          }
>