audio problem with avi file in virtual dub!!!!!

[colburn112]

ok ive got an avi file and when i open it in virtual dub i get a message saying "virtual dub has detected an improper VBR audio encoding in the source AVI file and will rewrite the audio header with standard CBR values during the process for better compatabillity. This may introduce up to 8890 ms of skew from the video stream. If this is unacceptable, decompress the *entire* audio stream to an uncompressed WAV file and recompress with a constant bitrate encoder. (bitrate:131.1=9.5kbps)"



ok heres the problem, i cut the avi file in half and extracted the audio to a wav file to get ready to encode with tmpgenc, i encoded the first half with no problems, but the audio and video is out of synch in the 2nd part, im guess thats what the error message i got when i first opened the file was talkin about. so i am in the process of extracting the complete wav file and encoding it back to mp3 with a bitrate of 128kbps, but im new with audio encoding and do not know if this is the right way to do it or not. IM goin to go ahead and try and see what happens and will post any progress but please any advice would be greatly appreaciated. Also do not know of a prog to join the encdode mp3 and the avi file so i can split it again and get it ready to encode with tmpgenc. thanks alot in advance.


here is the file info if it helps any i put in on here just in case

Video Stream
frame size, fps 576x304, 23.976 fps (41708)
# of frames (time) 133447 (1:32:45)
Decompressor DivX mpeg4 low motion
# of key frames 1621
min avg max, etc 862/12818/45489(20292k)
min avg max, etc 0/4636/50309(596920k)



audio stream
sampling rate 48000Hz
Channels 2(stereo)
sample precision 0-bit
Compression fraunhofer IIs mpeg layer 3 codec
preload skew 384 samples (0.01s)
# of frames 231908
min avg max total frame size 384/393/480(89098k)

[setarip]

"Also do not know of a prog to join the encdode mp3 and the avi file so i can split it again and get it ready to encode with tmpgenc."

You don't have to "join" the audio with the video. Just load both of them into TMPGEnc...

[Ozymandias]

Hello,

I had exactly the same problem and here's what worked for me :

I saved the audio into a WAV file with VirtualDub (so it was VBR MP3 at ~ 130.8 kbps in a WAV file) and recompressed it to a CBR MP3 file at 128.0 kbps using SoundForge (u can find a cracked version on Kazaa).
Then, I opened the original AVI file in NanDub, and used this new audio file as audio input (Audio > (VBR)MP3...). I set Direct Stream Copy for both Video and Audio and saved the new AVI file.
Unfortunately, it seems NanDub assumes the MP3 input to be VBR, so in this new AVI file, the audio data is CBR MP3, but the audio headers are still VBR MP3. This was confirmed in VirtualDub : when I opened the new AVi file, I still had the warning message (incorrect VBR headers), and that the headers would be rewritten as for CBR data, but this time it said the skew would be up to 0ms and the bitrate was 128.0 +- 0.0
Finally, I resaved the new AVI file with Direct Stream Copy for both Audio and Video, and this last AVI file worked fine.

Ozymandias

[colburn112]

thanks both for your help i will try that as soon as i get time and let u know of any success thanks alot

[Ozymandias]

Hello,

I just noticed that, because VirtualDub immediately detects and corrects the corrupted audio header, u can't get the complete audio track with the File > Save WAV... command. (the end is missing)
I used AVI2WAV to get the audio, and it works fine.

Ozymandias

[ronslinks]

HERE IS MY FIX FOR THE AUDIO VBR PROBLEM WHEN
CONVERTING AND OR SPLITTING AN .AVI IN VIRTUALDUB OR TEMPEG

EXPERTS:
LOAD AVI INTO VIRTUALDUB
UNDER FILE: SAVE .WAV
UNDER AUDIO: CLICK ON NO AUDIO
UNDER VIDEO: CLICK ON DIRECT STREAM COPY
UNDER FILE: SAVE AS .AVI

WE NOW HAVE XXX.AVI WITH NO AUDIO
AND XXX.WAV THAT IS AN INACURRATE CBR
THE XXX.WAV IS ALSO A .MP3 VBR ACCURATE

RENAME THE XXX.WAV TO XXX.MP3

ENCODE THE XXX.MP3 BACK INTO A .WAV USING WINAMP

WE NOW HAVE A .WAV CBR THAT IS ACCURATE

LOAD THE XXX.AVI INTO VIRTUALDUB
UNDER VIDEO: CLICK ON DIRECT STREAM COPY
UNDER AUDIO: WAV AUDIO - LOAD THE XXX.WAV

PLAY THE MOVIE AND CHECK FOR AUDIO SYNC.
IF THE AUDIO IS OUT OF SINK THEN...
UNDER AUDIO: CLICK ON INTERLEAVING AND HERE YOU
CAN MOVE THE SOUND FOREWARD TO SYNC WITH THE VIDEO.
AND WHEN ALL LOOKS GOOD SAVE IT.
UNDER FILE: SAVE AS .AVI

NOW IT WILL SPLIT PROPERLY IN VIRTUALDUB AND IT WILL
ENCODE PROPERLY IN TEMPEG
----------------------------------------------------------


NOVICES:


HERE IS MY FIX FOR THE AUDIO VBR PROBLEM WHEN
CONVERTING AND OR SPLITTING AN .AVI IN VIRTUALDUB OR TEMPEG





VIRTUALDUB.....



LOAD YOUR AVI INTO VIRTUALDUB

Rip from VIRTUALdub

audioFROM THE MENU BAR) FILE/SAVE .WAV

videoFROM THE MENU BAR)VIDEO/ DIRECT STREAM COPY
(FROM THE MENU BAR)AUDIO/ CHECK NO AUDIO
(FROM THE MENU BAR) FILE/SAVE AS AVI

OK NOW YOU HAVE AN .AVI WITH NO AUDIO AND A .WAV FILE.

THE .WAV FILE IS A CBR (CONSTANT BIT RATE) BUT IT IS NOT ACCURATE.
THE .WAV FILE ALSO RUNS AS A .MP3 VBR (VARIABLE BIT RATE) ACCURATE BUT
WE NEED A .WAV CBR THAT IS ACCURATE.

RENAME THE EXTENTION FROM .WAV TO .MP3
EXAMPLE "MEN_IN_BLACK2-.WAV" -TO- "MEN_IN_BLACK2-.MP3"

NOW THE .MP3 IS READY TO BE CONVERTED BACK INTO A .WAV CBR THAT
IS ACCURATE USING WINAMP.
---------------------------------------


WINAMP......


WINAMP WORKS PERFECT FOR ME. I AM SURE OTHER SOFTWARE WILL WORK BUT
I WILL STICK WITH THIS FOR NOW.

WINAMPFROM THE WINAMP MENU)
OPTIONS/ PREFERENCES/ OUTPUT/ DOUBLE CLICK NULLSOFT DISK WRITER PLUGIN .

HERE YOU CAN SET THE PCM FORMAT TO 44100 STEREO OR 48000 STEREO AND
THE BIT RATE, REMEMBER THE HIGHER THE NUMBER THE BIGGER THE FILE AND
THE BETTER THE QUALITY.

CHECK ONLY THE SINGLE FILE MODE BOX.

NAME THE FILE AND SAVE LOCATION CLICK "OK OR SAVE"

CLICK OK TO CLOSE THE PLUGIN WINDOW

CLICK CLOSE ON THE PREFERENCES WINDOW

LOAD THE .MP3 INTO THE WINAMP QUE AND HIT PLAY: THERE WILL BE
NO SOUND BECAUSE YOU ARE ENCODING..

WHEN DONE YOU CAN CHANGE THE "OUTPUT" OF WINAMP BACK TO
WINAMP WAVOUT PLUGIN SO YOU CAN HEAR AUDIO INSTEAD OF ENCODING.

NOW YOU HAVE A .WAV CBR THAT IS ACCURATE.
----------------------------------------------------



VIRTUALDUB.....


VIDEO: OPEN VIRTUALDUB AND LOAD THE .AVI THAT YOU SAVED THAT HAS NO AUDIO.

AUDIOFROM THE MENU BAR)
AUDIO/ WAVE AUDIO/ AND LOAD THE .WAV FILE THAT YOU MADE IN WINAMP

(FROM THE MENU BAR) VIDEO/ DIRECT STREAM COPY

PLAY THE MOVIE AND CHECK FOR AUDIO SYNC.
IF THE AUDIO IS OUT OF SYNC THEN...
UNDER AUDIO: CLICK ON INTERLEAVING AND HERE YOU CAN MOVE THE
SOUND FOREWARD TO SYNC WITH THE VIDEO.
AND WHEN ALL LOOKS GOOD SAVE IT.

(FROM THE MENU BAR) FILE/ SAVE AS AVI

NAME YOUR FILE AND HIT SAVE!


NOW IT WILL SPLIT PROPERLY IN VIRTUALDUB AND IT WILL
ENCODE PROPERLY IN TEMPEG
-------------------------------------------------------------

ronslinks@hotmail.com