[FFmpeg-devel] [PATCH] make analyze_duration work for streams with incomplete timestamps (mp3)

[Baptiste Coudurier]

Hi,

On 09/13/2009 03:41 AM, Reimar D?ffinger wrote:
> Hello,
> currently max_analyze_duration does not work for e.g.
> http://208.80.52.108:80/KDLDFM because the mpeg audio parser is very
> thorough in making a mess of timestamps.
> Basically, only every 4th packet has a timestamp and thus none at all
> have any duration.
> Attached patch handles this case by using the difference between the
> minimum and current dts for comparing against max_analyze_duration when
> we have no other duration info.
>
>
> ------------------------------------------------------------------------
>
> Index: libavformat/utils.c
> ===================================================================
> --- libavformat/utils.c	(revision 19824)
> +++ libavformat/utils.c	(working copy)
> @@ -2015,6 +2015,7 @@
>       AVStream *st;
>       AVPacket pkt1, *pkt;
>       int64_t last_dts[MAX_STREAMS];
> +    int64_t min_dts[MAX_STREAMS];
>       int64_t duration_gcd[MAX_STREAMS]={0};
>       int duration_count[MAX_STREAMS]={0};
>       double (*duration_error)[MAX_STD_TIMEBASES];
> @@ -2043,12 +2044,14 @@
>       }
>
>       for(i=0;i<MAX_STREAMS;i++){
> +        min_dts[i] =
>           last_dts[i]= AV_NOPTS_VALUE;
>       }
>
>       count = 0;
>       read_size = 0;
>       for(;;) {
> +        int64_t analyze_duration = AV_NOPTS_VALUE;
>           if(url_interrupt_cb()){
>               ret= AVERROR(EINTR);
>               av_log(ic, AV_LOG_DEBUG, "interrupted\n");
> @@ -2117,12 +2120,20 @@
>           read_size += pkt->size;
>
>           st = ic->streams[pkt->stream_index];
> +
> +        if (min_dts[st->index] == AV_NOPTS_VALUE || (pkt->dts != AV_NOPTS_VALUE&&  pkt->dts<  min_dts[st->index]))
> +            min_dts[st->index] = pkt->dts;

Can st->first_dts be used ?

-- 
Baptiste COUDURIER
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