[FFmpeg-devel] [PATCH] Add PlayStation Portable PMP format demuxer

Reimar Döffinger Reimar.Doeffinger at gmx.de
Mon Apr 4 20:31:35 CEST 2011


On Fri, Apr 01, 2011 at 08:33:34PM +0200, Michael Niedermayer wrote:
> On Fri, Apr 01, 2011 at 07:38:27PM +0200, Reimar Döffinger wrote:
> > Not yet complete, for demuxing AAC the AAC header must be generated
> > manually.
> > Possibly the decoder could accept the header as extradata to simplify
> > this.
> 
> > It also does not set pts/dts, which FFmpeg cannot handle.
> 
> I thought we had some code that handedl this, but maybe not or it got
> broken
> is there enough information for ffmpeg to figure out packet durations?

No idea. I tried setting pkt->duration explicitly to 1, but that changed
nothing.

> whats the set timebase?

The time base is the frame rate.

> > +    if (pmp->cur_stream == 0) {
> > +        int num_packets;
> > +        pmp->audio_packets = avio_r8(pb);
> > +        num_packets = (pmp->num_streams - 1) * pmp->audio_packets + 1;
> 
> > +        avio_skip(pb, 8);
> 
> what are these 8 bytes?

Some kind of delay between audio and video.
Guessing by other code I saw, difference between
audio start and video start and audio end and video end.
Here's a sample of the first few values:
time: 0 13878
time: 12244 1633
time: 24489 15511
time: 10612 3266
time: 22857 17143
time: 8979 4898
time: 21224 18776
time: 7346 6531
time: 19591 20409
time: 5714 8164
time: 17959 22041


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