Joining 2 AC3 5.1 files

[Sandra24]

I've got 2 AC3 5.1 files @ 384kbps and simply want to join them.

Any helpful suggestions here?

Couldn't find useful instructions through the search function.

Any help is much appreciated, thanks!

[b66pak]

copy/b audio1.ac3 + audio2.ac3 final.ac3
_

[Sandra24]

Sorry, but I can't follow you.

Would you please be so nice and explain it to me?

[Keiyakusha]

Use this from command line.
audio1.ac3 and audio2.ac3 is the names of files you want to join. final.ac3 - name of resulting file.

Or you can create text file in the same folder where you have your AC3 tracks, put there this command from b66pak's post, save, rename it to somefilename.bat then dubleclick on it.

[Sandra24]

the created file doesn't work, it's faulty.

Thanks though.

Any other suggestions?

[rica]

Haven't given it a go but i supposse it's gonna work:

eac3to audio_01.ac3+audio_02.ac3 finalaudio.ac3

[tebasuna51]

If audio1.ac3 and audio2.ac3 are correct and have the same parameters: channels, samplerate, bitrate, ...
the final.ac3 obtained with:

copy /b audio1.ac3 + audio2.ac3 final.ac3

must be correct also.
If it's faulty you must fix before the two ac3 parts with DelayCut. Put the delaycut log's if you have problems.

[kypec]

If audio1.ac3 and audio2.ac3 are correct and have the same parameters: channels, samplerate, bitrate, ...
the final.ac3 obtained with:

copy /b audio1.ac3 + audio2.ac3 final.ac3

must be correct also.

Just out of curiosity, does it mean that .ac3 file format has no special header at the beginning of the file (whereas many other file formats have)? Is it so that AC3 consists of distinct "chunks" where each of these has its own individual header repeating throughout the entire file (stream)?:stupid:
And why it isn't allowed then to merge files with different specs if they're gonna be decoded/played on-the-fly on per-chunk basis?

[tebasuna51]

Just out of curiosity, does it mean that .ac3 file format has no special header at the beginning of the file (whereas many other file formats have)? Is it so that AC3 consists of distinct "chunks" where each of these has its own individual header repeating throughout the entire file (stream)?
Exact.
There are only a remaining audio info from precedent frame ("chunk") just to preserve the continuity without initialize the decoder
And why it isn't allowed then to merge files with different specs if they're gonna be decoded/played on-the-fly on per-chunk basis?

Players can do this. TV can play 5.1 from a movie and continue with a 2.0 advertisement.

But authoring programs and some transcoders can reject this 'mixed' Ac3.
To make a DVD you need an Ac3 without changes.
If you use AviSynth you can't change the parameters in the middle of a decode.
If you decode to wav you can't start with stereo and continue with 5.1 ...
Many formats with a initial header can't support this

[Sandra24]

oh cool, thanks to you all, the command line worked now the second time I've tried it.

-Sandra