VirtualDub can't find an audio compressor while GSpot can for my avi. Help!

[yosarian]

I am trying to extract audio from an avi file in VirtualDub. When I open the avi it in either VD or VDM, I get a large "WARNING: NOTHING TO OUTPUT BFRAME DECODER LAG". When I check on the file info, it says for audio:
Rate: 48000Hz
Channels: 2
Precision: N/A
Compression: Unknown (tag 0055)

I looked up this avi in Gspot and it reads:
Codecs:
0x0055(MP3) ID'd as MPEG-1 Layer 3
4 compatible codecs installed

When I render the avi, DirectShowRender in Gspot informs me that:
AudioSrc: MPEGLAYER3 (MP3) (0x0055)
and that it could decode the audio with ffdshow Audio Decoder,
use MatrixMixer as the Audio Post-processor.

When I try and extract a wav file from my avi in either VD or VDM, it tells me "No audio decompressor could be found to decompress the source audio format." Even demuxing the audio in VDM to an mp3 doesn't work.

What can I do to fix this problem? I would like the final audio version something I can drop into TMPGEnc so I can encode this avi.

[guns1inger]

I think you have two seperate problems. B-Frame decoder lag is video related and, I believe, something to do with the bitstream structure. I know that using FFDShow and opening the file via avisynth with DirectShowSource() gets rid of the message.

Have you tried outputing an uncompressed wav file for the audio from Vdub ?

Also, perhaps the audio has been mis-identified. Try installing the AC3 ACM Decompressor and see what happens.

[celtic_druid]

VirtualDub uses ACM decompressors, you can have all the dshow decoders you want installed and it won't make any difference. That said windows comes with an ACM mp3 decoder. Perhaps yours is corrupt/missing?

"WARNING: NOTHING TO OUTPUT BFRAME DECODER LAG" means that it was encoded with bframes, but not packed bitstream.

There are numerous other ways to decode audio from an avi. mplayer, goldwave, etc.

[guns1inger]

Try LAME MP3 if nothing else works

[yosarian]

I was initally trying to get a wav file from VDub when I first experienced the problem.

As for the AC3 ACM decompressor's, I have them installed and they work fine. Earlier in the day I ran thru some audio that was in AC3 and had no problems decompressing it.

I will try a different tool (mplayer or goldwave) and see what happens.

[FulciLives]

If a DivX/XviD AVI has MP3 audio I always "demux" it using GOLDWAVE.

Just load the AVI into GOLDWAVE then save as a PCM WAV file.

For some reason GOLDWAVE seems to excel at this proceedure.

- John "FulciLives" Coleman

[celtic_druid]

AC3 requires an AC3 decompressor, mp3 and mp3 decompressor, so decoding AC3 means nothing.

I still don't think lame ACM includes a working decoder.

[Robert Simandl]

I get that message with xvid avi files quite often. When I do, I shut down Vdub and load the file into AviDemux. Then I separate out the mp3 audio and work with the video and audio separately from that point.

[profmuggs]

I figured out a workaround for the 0055 audio problem using virtual dub in direct stream copy mode to save the wav, then renaming the file extension to MP3, and using winamp's disk writer feature to convert it to a PCM WAV.
I wrote it up here...
http://www.modhotspot.com/0055_audio_error.php

[Sawyier]

profmuggs, I'd like to thank you for your solution! Although it didn't work fully for me..
When I convert the mp3 file to wav using Winamp (I've also tried mp3-2wav tool and the
result was exactly the same), but the output wav file was actually smaller (up to 2:10 minutes of difference)
than the mp3 input one, which is a considerable part of the sound.

So I was wondering if you also went through this last problem and, in case you did, how did it work for you? Could you find your way out?

[FulciLives]

It's easier to just use GoldWave ... one step and very simple.

- John "FulciLives" Coleman

[DarrellS]

I remember this error before but I think I just ignored the message and was able to work with the file with no problems.

Can you open and save other AVI files with MP3 audio? If not, you need LameACM-3.97, if so, you might try moving the slider to the second frame, choose the codec that the file was compressed with (XviD I assume), choose Smart Render for Video and Direct Stream Copy for audio and try saving to a new file.

I just ignored the error myself and edited and saved the file if I remember correctly.

[Placio74]

profmuggs, I'd like to thank you for your solution! ...

There is no need to use the option Save WAV... with Direct stream copy for MP3 audio in VirtualDub.

Probably no need decompress or recompress MP3 audio - rather enough re-mux A/V or fix MP3 stream and add again.

Try just extract audio (Export > Raw audio...) and...
- add as external (Audio > Audio from other file...)
- or try 'repair', example used Rebuild MP3 Stream in foobar2000 or some similar.

[Sawyier]

FulciLives wrote

It's easier to just use GoldWave ... one step and very simple.

I ended up concluding and doing that Thx a lot btw!

DarrellS, I ignored it once n the audio ended up desynchronized with the video.
But yeah, it varies a lot, even because the audio 0055 problem not always shows up for every file.

Placio74, I'll try your suggestion, thx!