[Ffmpeg-devel] mpeg transport streams

Måns Rullgård mru
Fri Jun 3 14:59:43 CEST 2005

"Marcus Hunger" <marcus.hunger at mugler.de> writes:

>> > Frames do not get interleaved which should be no problem at high
>> > bitrates.
>> The problems caused by not interleaving frames do not depend on the
>> bitrate.  The thing is, a large video frame can easily take 100 ms to
>> transmit, which means that the decoder would have to buffer that
>> amount of audio data.  Many (hardware) decoder have much smaller
>> buffers than this.
> I don't get your point. The decoder is forced to buffer data anyway
> until the pcr reaches the pts. Since they might differ of about
> 50000 (> 100ms) I don't see any improvement in interleaving.

I'm sure of the exact mechanics of it, but I've seen things break
without proper interleaving.  No real decoder is anything remotely
resembling the STD.

>> > I introduced setting a discontinuity indicator for the first pcr so
>> > concatenating ts-files should be possible. Doing this still causes
>> > cc-discontinuity-errors and I have no easy idea how to avoid them.
>> If you set the discontinuity indicator properly the demuxer should
>> ignore a discontinuity in the continuity counter.  I wouldn't be
>> surprised if many demuxers ignored the entire continuity issue.
> I wonder, if I implemented the standard right. My analizer says I
> didn't. But I have no clue what's wrong.

What analyzer are you using?  Just curious.

> Our settop-box in fact does not care about it.

As I said, most decoders will simply do the best they can with
whatever you throw at them.  The continuity counter is of very little
significance to the decoding process.

M?ns Rullg?rd
mru at inprovide.com

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