Whats the best way to sync AC3 files that have audio dely.....

[The Incredible Bulk]

Can anyone help me, what's the best way to make sure an AC3 file is in synch when it has an audio delay of for example -127ms.

Any help with this problem using maestro would be very much appreciated.

Thank

The Incredible Bulk

[Bart]

not sure if this will work or not as i dont know whether the ac3 files i used had audio delay or not and the movie i was authoring was in 2 parts. But all you do is right click the audio track in the movie timeline window and select create sync audio track. works for me with multiple files might work for you on a single file.

[Doom9]

the ac3 corrector: http://home.t-online.de/home/520072193568-0001/ may just be what you're looking for. Will be on my page starting tomorrow

[DSPguru]

sorry guys..
the delay corrector does NOT do what it claims it does.
i've tested it, and found out that it can only add full-frames delay. (multiply of 32milliseconds).
test it for yourself, take an ac3 stream, "correct" it by adding a 2ms delay for instance, than compare the two files, you'll see there's no difference at all.

Dg.

[mikeathome]

Ok, here's the howto:

1) Audio is delayed by x ms, means Audio is behind video
- all you have to do is delay video, how...
- at the beginning of the video track you add a blank (black) still picture (put a .bmp in front of the video in the timeline)
- this blank has to be same resolution as the video (say 720x480 for NTSC, 720x576 for PAL e.g.)
- the still will be expanded to the length of a GOP (by default Maestro stretches it to 15 frames lenght)
- now, go zoom the timeline down to 1 (one) frame display (the minimum possible)
- place video (if you don't have done that already ;-)
- place audio
- do the following math:
* my audio is behind by 127ms
* video is 1 GOP = 15 frames + 1 frame equals 40ms (PAL 1/25fps)
* still frame at the beginning expands video by 15 x 40ms = 600ms
* audio delay = 600ms - 127ms = 473ms ~> 12 frames
- grab audio with the mouse and shift it to the right to get a delay from the beginning by approx. 12 frames

2) Video is behind audio
- easy, zoom down timeline and shift your audio to the right (delay it), how much, ok, use some calculation from above

Believe me you'll find it in absolute synch.

mike