Is there a "definitive" solution for WDM audio synching?

[Mikele]

I've tried almost everything (software, drivers, settings) except throwing my TV tuner to the garbage. Audio goes progressively off-synch and it becomes very noticeable at about 30 minutes of capturing. I'm aware this is a known problem, but maybe someone has found out how to solve it.
I'm using a Leadtek Winfast TV2000 with iuLab's BT8x8 drivers. It's not a CPU issue, usually I capture @ 640x576 (PAL) with MJPEG 19 4:1:1 and my Tbird 1.1 uses only 30~40 of its capacity.

Am I expecting a miracle?

BTW, if I try AVI_IO in VFW compatibility mode (288 lines max) the audio is perfectly synched.

[808state]

Are you using the Audio in on the capture card? I had the same problems before connecting my source to an ATI All In Wonder. I disconnected the audio input to the capture card and ran my audio source straight into my soundcard input…problem solved

[Mikele]

My TV card doesn't have audio input, so I always go through my SB Live.
Well, I guess I'll have to buy an ATI (I've seen lots of entire movies and short videos captured with these cards and the results are always impressive -and in synch-) or wait for Pinnacle to code a stable XP driver for my DC10+.

[Scuba]

Try to capture 720X576 and not 640X576. 640 is not PAL compatible as far as I know.

What sound card are you using ? do you capture uncompressd audio or try to compress the audio to Mpg1 Layer 2 (for example) in real time ?

Defrag your hard drives.

Try to capture from a source other then VHS. Get some one with a DV camera and try to capture from it on the analoge capture. first 3 are technical normalities. the DV Vs. VHS is a known probelm. If the DV is in sync but VHS loose sync then it's the original signal coming from the tuner/VHS. Not much to do about it but using a TBC - Time Base corrector to fix the signal when it come into the capture card.

[unit01]

Hi Mikele,

I was not aware until recently you can get new drivers I think that's what they are that let you cap with avi_io at full res finally thankfully mercifully ;)




checkout the stuff at

http://btwincap.sourceforge.net/download.html




Good Luck

[Mikele]

@unit01:
Amazing! I was never able to capture both fields with a VFW application, not even with iuLab's optimized drivers. My first attempts with AVI_IO and Virtualdub weren't good at all (guess what? asynch sound!) but there are a lot of new things to try. I've noted that iuVCR doesn't work with these drivers. Not that I care, it has a lot of known synch issues.

@scuba:
Thanks for your tips, I had already tried all of them but to no avail :( It has to be a WDM problem, because with AVI_IO produces perfectly synched audio on my box.