Re: lost synchronization and CRC check failed

On May 9, 2004, at 7:15 PM, chikku belli wrote:
> I am new to audio and video decoder, hence would appreciate some help 
> in the beginning.
> I have an mpg file which has both and audio and video stream encoded. 
> I use libmpeg2 to decode the video and display it on the monitor. I 
> also use libmad to play the audio.
> when i decode the mpg file i store audio part of the mpg file in a 
> separate file (for ex: audio.ma2). After mpg file decoding is over, i 
> run madplay with the following options.
>  
> madplay -v /root/audio.ma2
>  
> I see the following error message on the screen.
>  
> MPEG Audio Decoder 0.15.2 (beta) - Copyright © 2000-2004 Robert Leslie 
> et al.
> error: frame 0: lost synchronization
>  00:00:00 Layer II, 224 kbps, 44100 Hz, stereo, CRC
> error: frame 3: lost synchronization
>  00:00:00 Layer II, 224 kbps, 44100 Hz, stereo, CRC
> error: frame 6: lost synchronization
>  00:00:00 Layer II, 224 kbps, 44100 Hz, stereo, CRC
> error: frame 9: lost synchronization
>  00:00:00 Layer II, 224 kbps, 44100 Hz, stereo, CRC
> error: frame 12: CRC check failed
[...]
> could anybody please tell me what could be the problem?

It would seem the MPEG audio has not been properly demultiplexed from 
the combined audio/video stream. I would check for errors in the 
demultiplexing process.

Hope this helps.

-- 
Rob Leslie
[email protected]