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Dr-
10 Mar 2002, 09:12 PM
hiya,
i often get sync audio problem when i encode realtime in divx (4.12) with a tv tuner card capturing software (iuVCR). But it's never the same amount of offsync.
Ex. in a 1 hour movie, the first 10 minutes can be perfect, then for the next 15 mins, the audio will be 1 seconds ahead, then it can get perfect for another 10 mins, then the video would be ahead 1-2 secondes.
This gets very complicated to use virtual dub or such to ajust framerate.
Anyone has a clue ?
Thanx alot

i use :
Duron 800
256 RAM
ATI radeon 64 DDR vivo
sound blaster live!

(includes of course that i give full priority to the capturing with no other apps open meanwhile).

Dr-
11 Mar 2002, 04:11 PM
i guess nobody has a clue about this one ... :(

Enchanter
11 Mar 2002, 04:56 PM
How is the audio interleaved?

Ndb
13 Mar 2002, 08:09 AM
Use the 1-Pass Quality setting in the DivX 4.12 codec, as this is supposed to be quicker as it uses a fixed bitrate (no jiggery pokery needed for VBR).

The file will be a bit bigger, but you can re-encode it later.

Also if hdd space permits use a quicker audio codec (i.e. less compression).

I'm not really up on realtime encoding, but what little I have done this helped out a lot.

maybe caprturing Video and Audio seperately may also help, but I doubt it much.

In fact I think I'm clutching at straws :smashead:

setarip
13 Mar 2002, 11:41 AM
It is my experience that you should always capture in either uncompressed or lossless format (NOT DivX-compressed) for video and Uncompressed PCM for the audio portion. Do your compressing of both video and audio under VirtualDub and you'll always be a synchronized happy camper ;>}

Dr-
15 Mar 2002, 08:40 PM
thanx alot for the tips guys, i really appreciate !

For the interleave, it's completly disabled...

And realtime capturing with no compression is a good idea, but it sure sucks alot of HD...
that's the only reason why i try to avoid it.

But i guess it's just that my comp ain't good enough to manage what i ask him...time to upgrade!
:smashead:

thanx again & keep on the good rips !:)

Ndb
16 Mar 2002, 05:58 AM
Here's a little snippet from the DivX codec's own help file regarding realtime capture.

The ‹Performance/quality› switch lets you decide whether you want the encoder to be done fast or to crunch everything to the smallest possible size. “Fastest” mode is optimized for real-time video capture. This choice is recommended for use with “1-pass quality-based” bitrate mode. ”Slowest” mode with “2-pass variable bitrate mode” is good for making video archives. The default value is “slowest”.


It may be of use.