Synch problem with MMC, but not VDub

jlietz · #1 12-01-2004, 01:51 PM

I posted similar to videohelp.com, but you seem to be the ATI authority...
I captured about 15 tapes today with my new Radeon AIW 9600 and MMC 9.02. In the past I always used Vdub with an AIW 128 Pro and had no problems. However, these new caps are horribly out of synch. WMP and ATI's File Player play the file correctly, but Vdub doesn't, which is important because I use VDub to edit. The edited clips are also out of synch. So I did some tests...
When I capture with ATI MMC 9.02 the audio and video lengths (from Vdub's file information page) differ anywhere from .46 to .48 seconds. The audio time is shorter so I hear the sound before the mouth moves. This happens whether I play the tape (VHS-C) on the orignal camcorder, or on my JVC HR-S9911U, or on my HR-S9911U in conjunction with the TBC-1000.
When I capture with VDUB using the HR-S9911U the difference is down to .04 seconds (not noticeable in the video) except now the video length is shorter. When I turn on the TBC-1000 the difference is .01 seconds.
So, it looks like for some reason ATI MMC 9.02 (I tested with 9.03 too) is not synching the audio and video, even though the signal should be in perect synch when it arrives at the capture card due to the TBC-1000. Any thoughts on what's going on or whether this can be rectified? I know that I can just use Vdub to capture and I'll be ok, but I paid good money for the ATI card and I expected to be able to take advantage of the software.
Thanks.

admin · #2 12-01-2004, 02:45 PM

I need to know all your capture settings in ATI MMC.

jlietz · #3 12-01-2004, 10:13 PM

I followed your guide except that I'm using PicVideo's MJPEG codec at quality level 19. So I'm capturing at 640x480 29.97 fps NTSC, and 48 Khz 16 bit stereo PCM.

jlietz · #4 12-01-2004, 11:41 PM

One minor change (typo) - I'm using a 9800 Radeon AIW not a 9600.

admin · #5 12-02-2004, 04:50 AM

Not all codecs, as I've learned, work on all systems. More of that lovely "practive vs theory" issue.

What happens when you use HuffYUV or entirely uncompressed AVI? And I'm assuming MPEG-1 and MPEG-2 captures are still fine, right?

strangepork · #6 12-04-2004, 04:34 AM

Hi,

I was having this problem originally with my MMC 8.5. Do you notice any dropped frames?? This was originally my problem with audio and video syncs. I upgraded to 8.7 and now its great. I too am using the TBC1000 with no probs ever since the upgrade. I used the MPEG-DVD capture settings, on LS's faq.

admin · #7 12-04-2004, 06:56 AM

Thanks, strangepork. Problems like this have so many possibilities.

Another new "problem" is ATI MMC 9.02 may be doing oddball things to video captures. Most notably MPEG-2 captures and GOP structure. This came to my attention a few days ago. It's still being looked into.

jlietz · #8 03-02-2005, 02:30 AM

To update, I finally (after 5 weeks!) received my warranty replacement card and have no apparent synch issues. Currently I'm using MMC 8.5 which was on the installation cd. - jlietz

admin · #9 03-02-2005, 03:20 AM

That's good to hear. As long as 8.5 is working, keep it. If anything seems screwy, move to 8.7 or 9.02.