[FFmpeg-devel] [PATCH v2] avformat/mov: adjust 0 values in stts

[Anton Khirnov]

Quoting Gyan Doshi (2021-12-28 17:43:47)
> As per ISO 14496-12, sample duration of 0 is invalid except for
> the last entry. However, some files may use it to stall dts
> progress in order to recover from a desync.
> 
> In addition, catch and fix 0 value for sample count.
> ---
> v2:
> 
> adjust dts if 0 duration is encountered
> 
>  libavformat/mov.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 351ecde770..7e90e24bd5 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -2970,16 +2970,22 @@ static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>          av_log(c->fc, AV_LOG_TRACE, "sample_count=%u, sample_duration=%u\n",
>                  sample_count, sample_duration);
>  
> +        if (!sample_count) {
> +        av_log(c->fc, AV_LOG_WARNING, "invalid sample count of 0 in stts for st %d at entry %u; changing to 1.\n",
> +               c->fc->nb_streams-1, i);
> +        sc->stts_data[i].count = sample_count = 1;

broken indentation

Also would be very nice to have a test for this.

-- 
Anton Khirnov