Audio offset

[robbiehales]

i have an AVI file but the audio is out, i hear it before i see it. i looked at the tutorial on this site but it didnt help, dont know why it didnt help but i followed it exactley but it made no fifference i even tryed offsetting the audio at stupid amounts like 4500 but when i saved and played back the AVI it was the same as before. any help or ideas to how i can sort the problem out?

[setarip]

Load the file into VirtualDub or NanDub
Set BOTH "Video" and "Audio" to "Direct Stream Copy"
Save with a new filename
Close VirtualDub (or NanDub)


Restart VirtualDub (or NanDub)
Load the NEW file into VirtualDub or NanDub.
Set BOTH "Video" and "Audio" to "Direct Stream Copy".
From the "Audio" dropdown menu, select "Interleaving"
Under "Audio skew correction", set an appropriate number of milleseconds (positive or negative) in the box labelled "Delay audio track by"
Save with a new filename

Let us know of your success ;>}

[robbiehales]

hmmmmmmm followed what you describe but had absolutly no effect on the movie at all the sound was still in the same place even after setting delay dont know why but it hadnt moved the audio track, its about 5 seconds ahead of the video, i looked at the tutorial on this site and that didnt work either lol its driving me nuts !!! cheers for the help

[setarip]

Hard to believe that adjusting the audio skew had absolutely no effect on the synching but, be that as it may, do the following:

1) Load the .AVI file into VirtualDub

2) From the "File" dropdown menu, select "File Information"

3) Post (here) EVERYTHING you see (both video and audio information), or post a screen capture .jpg of the information box

[SvB4EvA]

Thanks very much, I had that same problem with offset audio, and i had no idea on how to fix it. I used VirtualDub and set it perfectly now that movie is watchable! Thank you.

P.S.- You also mentioned another program to open the file with, is it better in virtualdub? VirtualDub worked well, but i had to constantly stop the video and then set a timing then play it agian over and over.

[setarip]

To SvB4EvA

My pleasure ;>}

The other program, NanDub, is a hack of VirtualDub. NanDub comes in handy when you have to deal with videos that contain a VBR (Variable Bitrate) .MP3 audiostream, rather than a CBR (Constant Bitrate) .MP3 audiostream - because VirtualDubcannot properly handle many aspects of VBRs...

[SvB4EvA]

I see, well thanks agian, I appreciate it.

[setarip]

Any time ;>}

[robbiehales]

is there a way of working out how many ms you need to move the audio or is it just a case if trying it bit by bit ??

[setarip]

"is there a way of working out how many ms you need to move the audio or is it just a case if trying it bit by bit ??"

Are you now saying you CAN see/hear an observable difference when adjusting the audio skew? ;>}


It's pretty much experimentation. In theory, if the audio is off by 5 seconds, the audio skew correction should be 5000ms (milleseconds). However, in the past, I've noted that I sometimes have to adjust by as much as three times the apparent lag. Remember, the figure you enter can be negative or positive, depending on whether the audio precedes or follows the video...