Help me with my VirtualFlub? Can't process AVI's with MP3 audio tracks

August 23, 2006 6:44 PM

How do I convince VirtualDub to work on AVI's with MP3 audio? Alas, not too much

I've googled around a lot, I've got LAME 3.96.1's encoder DLL and .ACM file in WINNT/system32 on my Windows 2000 box, and I've got VirtualDub (1.6.15) in full reprocess mode on the audio side, and yet, I still get the "No audio descompressor could be found to decompress the source audio format. (source format tag: 0055)" error as soon as I try to play or save out the clip I want. (The typo in that error message brought to you by Microsoft, who won't let me copy and paste it...)

I can navigate the file by frame or keyframe just fine, as long as I don't try to play audio. I've checked the few pertinent previously's, and like those people and a bunch on some web fora, I can play these clips with, say, mplayer...

I'm sort of out of good ideas.

I'm clipping video for a fan vid, and I have something like 38 x 42 minutes of MPEG2 to go through; I'd *really, a lot* like to avoid solutions that involve stripping the audio out, recompressing it, and relaying it; this *has* to be possible, right?

posted by baylink to media & arts (15 comments total)

You want virtualdubmod-mp3freeze.
posted by sun-el at 6:56 PM on August 23, 2006

I tried plain old virtualdubmod, but didn't know about the other one. I'll look into it, but, given most people's luck, keep those cards and letters coming, folks.
posted by baylink at 7:02 PM on August 23, 2006

LAME is only an encoder. The error is telling you that it cannot find a decoder, e.g. for preview.

Install FFDSHOW. It includes a VFW audio decoder.
posted by Rhomboid at 7:07 PM on August 23, 2006

And by the way, you can usually press Ctrl-C to copy the text of an error message box.
posted by Rhomboid at 7:09 PM on August 23, 2006

Oh, and another thing, if you plan to do VBR mp3 audio output you should use Vdubmod or Nandub, not stock Vdub, which chokes on the AVI VBR audio header (or something like that.)
posted by Rhomboid at 7:10 PM on August 23, 2006

As sun-el says, you want VirtualDub-MP3-freeze. The problem is with MP3's that are variable-bitrate.
posted by Civil_Disobedient at 7:10 PM on August 23, 2006

Hey, Rhomboid: should I get the 2004 alpha? Or is the 2002 release version good enough?
posted by baylink at 7:13 PM on August 23, 2006

As Rhomboid says, this is because the LAME ACM is an encoder only, not a decoder. On top of this, most other .mp3 decoders are not Video for Windows compatible (which vdub* requires). Install ffdshow or Radium .mp3 to get VfW compatible codecs.

And please don't plan to do VBR mp3 audio output, especially if you're creating .avi files - the AVI spec just doesn't handle variable bit rate anything, audio or video. Yes, there are hacks to make it work; yes, people do it; yes, it works sometimes; no, it's not a good idea. It's one of the Big 3 reasons people experience A/V sync problems. Besides, if the bit rate is 160kbps or better, the quality gain is hardly worth it in most video audio cases.
posted by Pinback at 7:24 PM on August 23, 2006

I'm reencoding to PCM; my target is a Premiere 6.0 timeline. I'm also reencoding to Cinepak video, though perhaps that's a mistake.
posted by baylink at 7:27 PM on August 23, 2006

Don't use any of the ffdshow binaries on sourceforge, they are older than dirt. They stopped posting binary releases there, I think because of patent issues. The binaries on afterdawn are recent and are free of crapware.
posted by Rhomboid at 7:34 PM on August 23, 2006

They did such a good job of making that download link pretty that I couldn't see it at all. Got it now.
posted by baylink at 7:38 PM on August 23, 2006

So, a combo followup: given that I have FFDSHOW, do I also need to be using the mp3freeze version?

And is that one as old as the other vdubmod?
posted by baylink at 7:39 PM on August 23, 2006

wait, isn't nandub an acceptable solution? its virtualdub + mp3 audio...?
posted by xospecialk at 1:49 PM on August 24, 2006

Well, I haven't looked at nandub yet, acutally (a big Real Work project is drawing most of my attention), but my goal is to reencode selected clips from AVI's with MP3 VBR audio grabbed from BitTorrent into something I can edit in Premiere, which currently is Cinepak with PCM audio.

The problem -- which may be fixed now; I've grabbed FFDSHOW but haven't had time to install it -- was *reading* the MP3 audio; I don't plan to write any.

I should have time to install the other versions and test tonight; there are some best answers in here -- I'm just waiting to see which one's bestest. :-)
posted by baylink at 3:10 PM on August 24, 2006

even with FFDSHOW installed, -mp3freeze was the only one that would play the clip, but the audio cut up shortly after I hit play, though the video continued moving.

If I stopped it and then hit play again, same thing.

I guess I'm going to have to do this the hard way, though I'll try out nandub as well....
posted by baylink at 10:03 PM on August 24, 2006