Joining two AVI files with AC3 audio

[aLuZINK]

Hi, first of all i'd apologize if i post this one at the wrong place or if someone has already asked the similar question..

i have this film compressed into 2 avi files, which are coded by XviD and the audio format is AC3. i want to join these 2 files into one with VirtualDub. the problem with the joined AVI file is at the point the content of the second file begins, the audio suddenly dropped to almost silence. if i drag the progress bar to any later part of the movie, the audio are again fine. i guess it could be the header problem or something, but i just have no clue how to deal with it... it would be GREAT if i could get some help here, i thank you in advance!

[Paulcat]

You can turn both avi files into matroska files, and join them no problem with MKVToolnix. And then extract to create a single avi after. Works pretty fast too

[aLuZINK]

eh.. i've never experienced mkv format before.. guess i'll have to learn first. but i'd ask, won't this method damage the quality of the video? or mkv is a no-damage codec... anyways off i learn, and thanks for the tip!

[stephanV]

no need for matroska...

perhaps joining with AVImux GUI or VirtualDubMod is a better idea. Vanilla VirtualDub does not really support ac3.

[vav]

Hi, first of all i'd apologize if i post this one at the wrong place or if someone has already asked the similar question..

i have this film compressed into 2 avi files, which are coded by XviD and the audio format is AC3. i want to join these 2 files into one with VirtualDub. the problem with the joined AVI file is at the point the content of the second file begins, the audio suddenly dropped to almost silence. if i drag the progress bar to any later part of the movie, the audio are again fine. i guess it could be the header problem or something, but i just have no clue how to deal with it... it would be GREAT if i could get some help here, i thank you in advance!

maybe demux the (joined) ac3 file, run it thru ac3fix (search for that util) and then remux with vdubmod. That should 'clean' the wrong header caused by the joint procedure.

[Paulcat]

eh.. i've never experienced mkv format before.. guess i'll have to learn first. but i'd ask, won't this method damage the quality of the video? or mkv is a no-damage codec... anyways off i learn, and thanks for the tip!

AVI and MATROSKA are both "containers", the actual mpeg4 video and ac3 audio would be unchanged, just moved to a new container. Matroska can also contain subtitles, chapters and other stuff that Avi cannot. I have found it handy to join files, try it if your other methods do not work. Look for MKVToolnix and MKV Extract GUI. Actually, if you are interested, you can try it anyways, just to learn a bit more...

[yaz]

@aluzink
if the parts are ok, avimuxgui will perfectly join them. check that 1st. while loading the parts into avimuxgui, it checks them so u will see whether they are ok ;) if not, pls, report the problem.
the bests
y

[aLuZINK]

you guys are great!! thanks a lot!

actually before posted my question i had tried Nandub and aviMUX but they didn't work.

this ac3fix is the exact right thing for me! it deleted the false header and now i have joined the two parts with no more problem!

[vav]

this ac3fix is the exact right thing for me! it deleted the false header and now i have joined the two parts with no more problem!

glad to be of help ;)

[El Enmascarado]

AVI and MATROSKA are both "containers", the actual mpeg4 video and ac3 audio would be unchanged, just moved to a new container. Matroska can also contain subtitles, chapters and other stuff that Avi cannot. I have found it handy to join files, try it if your other methods do not work. Look for MKVToolnix and MKV Extract GUI. Actually, if you are interested, you can try it anyways, just to learn a bit more...
Do u mean to tell me that you can move the video and frame it into another extension? if so how is it done? don't u still have to recompress it in mkv codec?

[stephanV]

Matroska is not a codec, neither is AVI. They are bot encapsulation methods for holding encoded (or uncompressed) streams, like mpeg4, ac3, mp3, etc.

If you change the container by remuxing, the encoded streams stay unchanged.

[Paulcat]

And Matroska has the benefit of being able to do it and use up slightly less space on your HD than an AVI. Having subtitles included is also a nice touch.