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4lex
19th December 2001, 11:25
I've made an AVI with AC3 audio stream using Flask to compress the video and extract the audio, and Nandub to mux the audio in. Try as I might I can't seem to get the audio synced, it seems to be going in and out of sync as the movie plays, the offset not remaining constant.

I tried interleaving the audio at default settings, and every 64/96ms as doom9 suggests in his guide, but still no dice. Can anyone suggest what I might have done wrong?

Many thanks,
Alex
4lex
20th December 2001, 12:59
any suggestions?
ChristianHJW
20th December 2001, 14:11
... download PowerDivX 3.11 from Doom9 and set AC3 output device to 'default WAV out device' and report what happens ...
4lex
20th December 2001, 14:56
OK, will do, thx. I'm out on the p155 til saturday though, so I'll post back then.
4lex
24th December 2001, 01:15
Originally posted by ChristianHJW
... download PowerDivX 3.11 from Doom9 and set AC3 output device to 'default WAV out device' and report what happens ...

Hmm - not much. In fact nothing at all - I'm getting AC3 output on my SB Live device from BSPlayer, but no sound at all from PowerDivX :(

-edit-
Duh, what an idiot. I had the volume at zero...... sometimes overlook the simplest things. Still having the sync problem though :(
-edit-
MaTTeR
24th December 2001, 02:40
Did you try the default interleave settings by chance? 500/1 works me.
4lex
24th December 2001, 10:48
Yeah, tried that, and plenty others. Seems 40/40ms works best, with a delay offset of 150ms, however it seems the audio track is ever so slightly 'stretched' if that's possible, and the sync delay is very slowly growing throughout the playing time until it's about 600ms delayed by the end of the movie.
pdontthink
19th January 2002, 12:22
4lex, did you reslove your problem?
was it cuz you were using Flask (said
to have synch issues)?? i have what
i think might be the same 'growing
synch' problem, so i'd be curious to
hear what you did.
ChristianHJW
19th January 2002, 14:37
@4lex :

In PowerDivX try to set your AC3 audio to 'Default Wave Out' instead of using DirectShow sound and report whats happening ...
4lex
21st January 2002, 22:48
Thanks for the replies, it seems the issue is indeed PowerDivX related, as the sync issue isn't evident in wmp, but I can't figure out how to get ac3 audio from wmp.

Sadly my main rig is down at the moment as I'm missing a graphics card which I RMA'd over a month ago, so I haven't tried anything else recently, this c533 rig is pitifully slow :(
MaTTeR
21st January 2002, 23:17
Hmmm...the new 3.12 PowerDivX doesn't give me sync issues anymore.

Did you try ZoomPlayer?
pdontthink
21st January 2002, 23:39
Strange, you should be able to get ac3 sound in
WMP easily, just make sure the audio filters from
doom9's software page are installed. I can get
perfect sound in WMP, that is until I make an avi
with two audio tracks, then it, ZoomPlayer, and
PowerDivX start crashing like mad...

also, some good manual synch ideas are at:
http://www.doom9.org/virtualdub_procedures.htm#mansynch