[Ffmpeg-devel] h264 decoder/ts-streams

[Derk-Jan Hartman]

On 3-nov-2006, at 18:04, Julian Scheel wrote:
> Hi
> Am Freitag, 3. November 2006 17:57 schrieb Nico Sabbi:
>> no, demuxers doesn't have to do this.
>> Use the stream_type in the pmt to determine the type of the video  
>> stream
>> and let the decoder to the rest (it will search the right syncword)
>
> I thought this is what xine does normally and what does not work  
> with xines
> current implementation.
>
>> as above, this is decoders' job; besides, in h264 0x000003 sequences
>> have to unescaped
>
> hmm, ok. But why does VLC do that?

Because early on, the decoder/parser in libavcodec did NOT do that,  
but crash instead.
As a matter of fact, in case the first nal is not a SPS/PPS pair, it  
still tends to crash regularly atm. (no i don't have samples. this is  
just by experience watching live TS streams).

Also, in VLC not everything by definition goes to a decoder.  
Sometimes the data is just repacked for one or more other  
destinations. Therefore all h264 data will be packed internally to  
the startcode prefixed version, and be later reprocessed to fit best  
it's final destination streams.

>>> and so on.
>>
>> can you post a sample?
>
> You can grab a short samle-file here
> http://www.jusst.de/files/sample.ts
>
> mplayer and ffplay can play it without problems. xine needs the  
> patch I posted
> on xine-list
> (http://sourceforge.net/mailarchive/forum.php? 
> thread_id=30787841&forum_id=7131)
> to make audio work, but video still won't work.

DJ