AC3 with internal changing format => mute

Mar 4, 2009 at 6:48 AM
Edited Mar 4, 2009 at 6:50 AM
I wanted to decode an AC3 file with NicAudio (r202) via AviSynth
NicAC3Source outputs only mute from the point where the format changes in the AC3 file

"Project X" (http://sourceforge.net/projects/project-x) logs the following when parsing the file:
-> src_audio: AC-3, CM, 2/0(2.0), dn -23dB, DS, 48000Hz, 384kbps @ 00:00:00.000
-> src_audio: AC-3, CM, 3/2lfe(5.1), dn -27dB, cm -3.0dB, sm -3dB, 48000Hz, 384kbps @ 00:00:02.528
-> src_audio: AC-3, CM, 2/0(2.0), dn -23dB, DS, 48000Hz, 384kbps @ 01:26:01.984

With Project X I could rewrite the packet headers to make all 3/2lfe but the problem remains: mute after 2 seconds.
Project X logs now:
-> src_audio: AC-3, CM, 3/2lfe(5.1), dn -27dB, cm -3.0dB, sm -3dB, 48000Hz, 448kbps @ 00:00:00.000
-> src_audio: AC-3, CM, 3/2lfe(5.1), dn -27dB, cm -3.0dB, sm -3dB, 48000Hz, 384kbps @ 00:00:02.528
-> src_audio: AC-3, CM, 3/2lfe(5.1), dn -27dB, cm -3.0dB, sm -3dB, 48000Hz, 448kbps @ 01:26:01.984

I don't know any program that splits the file exactly at those packet positions.
Coordinator
Jun 25, 2009 at 2:38 PM

AviSynth need a fix number of channels, bitrate and samplerate along the full stream.

Is not enough change the headers. You need split the stream in coherent fragments with DelayCut for instance