[FFmpeg-devel] [PATCH] stop av_find_stream_info per packet dts

[Michael Niedermayer]

On Sat, Mar 14, 2009 at 11:39:26PM -0700, Baptiste Coudurier wrote:
> Michael Niedermayer wrote:
> > On Sat, Mar 14, 2009 at 08:50:25PM -0700, Baptiste Coudurier wrote:
> >> Michael Niedermayer wrote:
> >>> On Sat, Mar 14, 2009 at 08:25:25PM -0700, Baptiste Coudurier wrote:
> >>>> Hi
> >>>>
> >>>> It seems stopping av_find_stream_info by packet duration causes a
> >>>> problem when a packet with long duration (still image, sub) is very long.
> >>>>
> >>>> Scenario:
> >>>> 1 video stream containing a single image with very long duration
> >>>> 1 video stream cfr.
> >>>>
> >>>> Demuxing will happen in this order since dts are in this order.
> >>>>
> >>>> av_find_stream_info will stop after the single image, while the next
> >>>> packet dts will still be < max analyze duration.
> >>>>
> >>>> I'd like your opinion on this I don't know if this might have side effects.
> >>> i think the idea is good but dts might not start at 0 (cut mpeg-ps/ts being
> >>> an example)
> >>> also before you write a patch that sums dts differences, this can break
> >>> with timestamp discontinuities.
> >>> maybe something like using the previous sum of durations for each stream
> >>> instead of the latest?
> >>>
> >> Like this ?
> >>
> >
> > [...]
> > 
> > no i meant to move the codec_info_duration check before the change that is
> > 
> > if(codec_info_nb_frames[st->index]>1){
> >     if (st->time_base.den > 0 && av_rescale_q(codec_info_duration[st->index], st->time_base, AV_TIME_BASE_Q) >= ic->max_analyze_duration)
> >         break;
> >     codec_info_duration[st->index] += pkt->duration;
> > }
> > 
> > a possible problem with your suggestion is that it might never reach
> > the break if some stream simply doesnt contain any (more) packets
> > 
> 
> Right, I understand now.
> 
> Patch attached.

looks ok

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I do not agree with what you have to say, but I'll defend to the death your
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