Mp3 audio codec in Virtualdub

[myck]

Hello. I need help with a problem. I have a movie that gspot shows this on audio: "Codec: 0x0055 MPEG-1 Layer 3; Info: 48000Hz 128 kb/s tot , Joint Stereo LAME3.96r; Stat: Codec installed". At first I got the "No audio decompressor could be found to decompress the source audio format". Then I installed lame_acm 3.97 version but when i loaded the movie in virtualdub it says: "Error initializing audio stream decompression: No installed audio codec could be found..... Make sure you have the required codec".
What should I do? As Gspot says the codec is installed. Why virtualdub doesn't reconize this codec? I'm using vd v1.6.17.

[DarkZell666]

did you actually close and re-open vdub ? vdub detects codecs on startup, not when opening the codec list :)

I believe you did the right thing though, I can't help you any further I'm afraid :/

[myck]

I got this error for weeks now. And it keeps saying this all the time. I posted this because my dvd-player does not read this movie and I want to re-encode, but VirtualDub doesn't let me. Maybe it's something in the registry, I don't know. Or maybe there is another way to re-encode this movie. Thank you.
PS: Audio is mp3 vbr.

[DarkZell666]

The other way is to use avisynth, using directshowsource() instead of avisource(). But you're just as likely to run into codec problems (unless you have ffdshow installed of course ;)).

In the end, if all goes well, you'll be able to load your avs script into vdub and encode from there.

[myck]

OK. I installed VirtualDub 1.7(experimental) and this works. When the movie is loaded gives this message: "AVI: A non-zero wBitsPerSample value was detected in the MP3 audio format structure. This has been corrected in-memory to zero for better compatibility with commonly installed MP3 audio codecs." Thank you DarkZell for your time.

[DarkZell666]

You're welcome :)

This error message sounds wierd btw ... A non-zero wBitsPerSample value was detectedwBitsPerSample should be 16, not 0, so I don't see why vdub isn't happy about it being different from 0 ... :/ You can't do much about that anyway ^^

Thx for sharing your solution though, if others run into this problem, they'll have an easy solution :)

[squid_80]

This error message sounds wierd btw ... wBitsPerSample should be 16, not 0, so I don't see why vdub isn't happy about it being different from 0 ... :/ You can't do much about that anyway ^^
First off, LAME is a compression only codec, it doesn't have decompression capabilities (unless you have a hacked build).

For compressed formats wBitsPerSample should be whatever value is defined for that format. For most it is defined to be 0. The default mp3 acm codec that comes with windows (Fraunhofer, has a few variations: l3codeca.acm, l3codecp.acm etc.) refuses to decompress anything that doesn't have wBitsPerSample = 0 (the directshow version seems to be more forgiving). We figured this out on the virtualdub forum and patches have since been added to virtualdub and avisynth to handle it.

I'd still like to know what program is writing these bad audio format headers to file a bug, but no-one seems to know where they come from.

[DarkZell666]

Ahhhh so the lame acm thing is only for encoding ? oO Wierd, what uses acm for audio encoding anyway, appart from sndrec32.exe ? XD (ok just kidding, I've had quite a bunch of wav-editing apps that only used ACM ;))

Thx squid for clearing these silly ideas out of my mind anyway ;)

So basically, myck, you were unlucky to encouter a malformed file ^^

[setarip_old]

@myck

Hi!

"Squid_80" stated:I'd still like to know what program is writing these bad audio format headers to file a bug, but no-one seems to know where they come from.

Would you be good enough to tell us what program(s) you used to create this .AVI?

[alan_erickson@hotmail.com]

Sorry to bump an older thread, but I'm having the same problem with virtualdub and the program that is creating the "bad" files is Snapstream Beyond TV. I've tried a ton of different things to get things working without any luck. Also have tried Virtualdub Mod along with the latest 1.73 without any successs. If anyone is interested I can send them a small little sample. PM me.

[alan_erickson@hotmail.com]

FYI. Squid_80 looked at a file of mine and sent me a PM that "fixed" the problem for me. Below is the PM he sent me:

" It's got a bad audio header, different to the wBitsPerSample problem but I have seen it before. So at the moment unfortunately the only way to get the files to load into virtualdub is to hexedit them first. Virtualdubmod on the other hand can process them without any hex-editing if you go to options->preferences, on the VDubMod tab scroll down to audio and put a tick in the Priss Rocks! box, and save changes. "

I've also sent a support request to Snapstream BeyondTV , but we'll have to see if they feel the need to do anything. It would be nice to be able to get it to work in the basic VirtualDub since it has more audio options available.

Edit: I figured out how to get the additional audio encoding options available for VDubMod. Snapstream doesn't seem very interested in fixing their header.

[Stabmaster-Arson]

Hi, I have the exact same issue, to work around my problem i merely used avisynth> avisource reader. It did NOT require directshow........

Very odd.

When I load the video into vdub mob the error I get is
"AVI: Truncated or invalid MP3 audio format detected (18 bytes, should be 30).
Attempting to fix.
Then everything loks ok except the acm will not decompress.

Avisynth>avisouce() worked fine tough so I am good to go.

Also, I am not sure either which program wrote this mp3 bitstream.

Aother interesting piece of information, I truncated the video with direct stream copy, and the resutling stream does not produce an error when loaded into vdubmod, however it is still unable to decompress via acm when I try to reencode the audio.

(The bitrate was 320 and to fit on one DVD r I needed to reencode 6 of the files into 160 kbps.

I tested the unmodified files on my LG dvd player and they all work, before and after modifying, but I guess I should reencode all the audio to ensure future compatibility.

[setarip_old]

@Stabmaster-Arson

Hi!

Also, I am not sure either which program wrote this mp3 bitstream.1) What software and procedures did you use to create the .AVI?

2) Please load the .AVI into GSpot and post a screen capture back here...

[Stabmaster-Arson]

1: This avi was not authored by me.

I did trim a section of video out of the bad file using vdubmob 1.5.10.2 using direct stream copy and resultant file did not give the error when loaded into Vdubmod, however, when trying to recompress the audio of the truncated video it is still not possible directly; avisynth works around the issue perfectly with the original file and the truncated file I made form the original.

2) I've never posted a screenshot before but here goes....

If any develop is interested in getting a piece of this for analysis, let me know.

[setarip_old]

This avi was not authored by me.Sorry, but I can't provide any further assistance...

[Foofaraw]

It would be cool if someone wrote small utility to simply set wBitsPerSample to 0 - it screws up hardware playback in some players when its not 0 - oh well.

[DarkZell666]

Have you tried hex-editing the file ?
Edit : reading further back, VirtualDub 1.7.X can apparently fix the issue. VirtualDubMod doesn't do that, and I believe you should stop using it (unless you have a very specific reason to do so ?)