[Libav-user] Transcoding Decoding_Encoding to MP4/h264 - asynchron tracks

[Silver]

Can i somehow prevent this video/audio sync drift? 
I'm going back to Zero... is there a way to narrow it down?

Im done with Trial and Error... if such oldschool mail list can't help me...
is there some other place where i can look? It seems People are rar with
some insight and KnowHow?
I started to read different things.. and somehow i feel that this whole
time_base,pts/dts, keyframes has something to do with it. 
Is there no Bulding-Plan? Step A, Step B, Step C? 

http://www.ttcdas.com/products/daus_encoders/pdf/_tech_papers/tp_2010_time_stamp_video_system.pdf
<http://www.ttcdas.com/products/daus_encoders/pdf/_tech_papers/tp_2010_time_stamp_video_system.pdf>  
http://en.wikipedia.org/wiki/MPEG_transport_stream
<http://en.wikipedia.org/wiki/MPEG_transport_stream>  

I use the avcodec libs which comes from ffmpeg 1.2.4.  What is the different
between 1.2 and 2.1 ffmpeg? Because it makes such a huge jump 1.2 -> 2.0,
instead 1.3,1.4,....   is it somewhere explained? Maybe i found it already
and forgot it...
Should i try the new avcodec libs from 2.1 ?


Im a Newbie i totally have no clue..  
-----

totally agree:
[offtopic]
http://ffmpeg.org/pipermail/libav-user/2013-April/004304.html
[/offtopic]


Silver wrote
> Hello,
> 
> i dont have a solution now, why my video files gets out of sync after
> 2-4mins.
> If you use the scrubbing tool or play and pause, it gets back to sync.
> 
> I heard something that you have to set a sync point for a certain i-frame,
> for the encoder. 
> Isn't this the pts? I mean Video 1-Frame doesnt mean it has the same
> length like 1 Audioframe, but if the pts/dts aren't correct should it be
> asynchron the entire clip? The weird thing is that it is sync for at least
> 1-3 min and so more you play, so more it gets asynchron.
> 
> But still ... im confused why play/pause, scrubbing brings it back to
> sync.
> ---
> 
> If im searching for sync points here... there are some attributes.
> ffmpeg source
> <https://gitorious.org/ffmpeg/ffmpeg/source/28240a60c1b5ce276e947ba013271ec009adc078:libavcodec/avcodec.h>  
> 
> But i have no clue at all... what i can do. 
> Any help possible?





--
View this message in context: http://libav-users.943685.n4.nabble.com/Transcoding-Decoding-Encoding-to-MP4-h264-asynchron-tracks-tp4659230p4659448.html
Sent from the libav-users mailing list archive at Nabble.com.