I'm having a problem with delay of audio in my MPEG-2 file.
I have a 700mb AVI file and want to extract the WAV file.When i open the file up with virtual dub it says:
AVI: Variable bitrate (VBR) audio detected. VBR audio in AVI is non-standard and you may encounter sync errors up to 17783ms when attempting to extract WAV files or processing the audio in Direct Stream Copy mode. Full Processing mode is recommended to decompress or recompress the audio. [bitrate: 125.4 +- 17.7 kbps]
Now after I have extracted it using the Full Processing mode. Then I use TMPGnc to make my MPEG-2 file but it still has a audio delay of about 3 seconds.
I have wasted hours trying to fix it. Can someone help me please.
Try AviMux_GUI: http://www.alexander-noe.com/video/amg/ Drag and drop your file in the top window and leftclick it. Then, select "generate data source". In the window below, leftclick audio and the delay in ms will appear to the right. Select "start" saving and naming the file where and what you want. You'll have a new file to use in a minute or so. Never tried an MPEG but should work.
I tried what you said to do. When I save it as a new AVI file. The new file has a little delay. When my orginal file didn't have a delay. My orginal AVI file has no delay but when i change it to MPEG-2 it has a delay.
Well, I guess it doesn"t work with MPEG. Even though the origonal AVI plays fine, run it through AviMux_GUI and you'll see the delay. You'll have to start over with the new file, as far as I know.
You extract the WAV because the encoder doesn't understand the MP3 VBR compression, which you remove by decompressing the audio stream from MP3 to WAV.
If you encode the AVI 'as it is' you'll have that the movie becomes gradually more and more A/V unsync.
You can do directly AVI --> DVD (or AVI --> MPEG in general [MPEG-1 or MPEG-2]) only if the sound is compressed CBR : either MP3 CBR or AC3.
MP£ VBR has better quality (typical use in music), and it is good when you make an AVI to be read on a Player which can direcly read DivX fils, since:
- a MP3 VBR 128 means that the averagebitrate is 128 kbps, but depending on the point of the movie, the bitrate used can lower or rise (imagine a range 64 kbps - 192 kbps , which is usually decided by the sound encoder).
- a MP3 CBR 128 means that the bitrate of the sound file is 128 kbps everywhere.
Alas, the AVI encoders cannor underatand the MP3 VBR compression, so create a gradually un-sync MPEG file. Decompressing it to WAV is the only trick to cancel this issue.
For instance, if I have an AVI with MP3 VBR 128 kbps compression, I do:
1) extract AVI --> WAV
2) compress WAV --> AC3 160 kbps (since VBR 128 is better than CBR 128)
3) convert AVI --> M2V
4) author M2V + AC3 160 kbps --> DVD
I confess, I use TMPGEnc checking the box 'create the output as elementary streams' . I never create a MPG I create a M2V and an audio stream (MP2 or AC3).
Then, I author the DVD.
Therefore I made the stick 'elemantary streams' (which no one uses).
I prefer to keep separated the necessry steps, to make a DVD:
a) CONVERTING - AVI --> Video + audio
b) AUTHORING - M2V + AC3/MP3 --> IFO, BUP, VOBs
c) BURNING (placing those stuff in the video_ts folder of a DVD)
Quote:Alas, the AVI encoders cannor underatand the MP3 VBR compression, so create a gradually un-sync MPEG file. Decompressing it to WAV is the only trick to cancel this issue.
Although Nero seems to have sync issues with VBR audio, but sometimes choosing LPCM audio instead of DD will work, ConvertXtoDVD handles VBR audio Xvid's quite nicely without the need for any other steps. Very rarely does it have a problem and when it does there are usually other issues with the XviD.
