AVI sync issue! OK gurus, explain this…

[Almost Human]

Why do AVI captures gradually drift out of a/v sync?

After capturing AVI from any source, say 1.5 to 2 hours worth, the audio is approximately 3/10 second different than the video. Now I know that doesn’t sound like much, but it does detract from a really good mystery ending.

I have captured (VCR and TV) with Pinnacle VideoStudio 7.15 with Firewire, VirtualDub 1.5.7 using ATI MMC 8.7, Sony DCR-TRV240 pass-through using Firewire and DVIO on three different computers. I used Media Player, and ATI MMC8.7 for playback. All of these with the same results, in sync at beginning, then 3/10-second difference at the end. I used my eyes to verify that the sync error was gradual, and VirtualDub reports the same difference in clip properties.

I have been correcting this, after capture, by VirtualDub “full stream processing” and changing the video frame rate so as to match the audio. This works very well, but it is another time consuming step.

I would like a reasonable explanation of this phenomenon. Anyone care to give it a go?

[cinemakatherine]

Hello! Your the first person I've ever found on the internet that has the same exact problem as me! I've been looking day and night for a solution myself. The Pinnacle Support people have been emailing me back and forth for about a month now, and still no luck. I can't tell if they're really trying to help me or just trying to put me off! Anyway, I've been going in to my other video editing program (Video Explosion) and moving the audio back the three spaces. I absolutely hate having to do that! ..and sometimes that doesn't even work! Sometimes I find that the audio is only 3/10 out of sync for the first hour or so, then the rest is closer to being in sync. It's an awful problem! I have no idea what to do! It seems like we're the only two people having this problem. I look forward to seeing if anyone can help on this forum. Good luck! Hope someone can help us both!

- Pinnacle support recommended Scenalyzer once, but it doesn't work. Every once and awhile I'd get these awful squeaking noises, and the people at Scenalyzer said it was a problem that couldn't be fixed. (something having to do with Pinnacle cards and Scenalyzer together) I just thought I'd let you know that it didn't work either! Bye!

- Katherine

(I've attached a picture showing how I move the audio manually. Does it look like the same problem you're having?) The picture is at http://www.sysopt.com/forum/attachment.php?s=&postid=1011621

[proxyx99]

If it wasn't an issue why would Canpous advertise thir ADVC-100 as "locked-audio" device. Conversely there ARE devices that have problems with keeping up with video stream. Your is probably one of them. Firewire doesn't mean "fireproof". Btw. any compamy suggests that for optimum results capture should be as small as possible or split accordingly. This issue can be easily corrected in NLE like Vegas.

[Almost Human]

Knock, knock.

[Smells_Like_Feet]

Well, I once suffered from the very same problem (I think). The solution that worked for me was to capture in Type 1 DV. (Pinnacle software will only capture in Type 2 DV and this is apparently incompatible with sony digital cameras.) I now use the WinDV capture progam (freeware ) which allows the user to specify which dv type to capture in. It has worked everytime without flaw for me. If you want to do some editing in Pinnacle or any other software package that will handle only Type 2 DV then you will have to convert the footage (there is freeware available to do this also, but the extra step is kind of a pain). I know that Ulead videostudio accepts both types and has been useful for my editing needs.

Give it a try and let us know how it works. Good Luck.

- Smells_Like_Feet

[Gazorgan]

The problem is 2 hours in VDUB. VDUB wasn't writtent to capture, but it captures. The problems arise in trying to maintain a perfect 29.97 fps rate. It can gradually slip since it's capuring the audio and video seperately and muxing on the fly. Other issues can arise from dropped frames. That is the video drops a frame but the aduio doesn't, have you dropped any frames?

Try IUVCR. I've done 3 hour captures with no sync loss (use Video as master and force sync the Audio).

[Almost Human]

I was using Ulead Video Studio 6, but the titles and transitions stunk.

I have been using DVIO to transfer from my Sony camcorder, but the program defaults at DV type2. If I used WinDV, could I set it to transfer at type1?

Will VirtualDub accept type1 for cutting out commercials?

Thanks

[Gazorgan]

I don't think VDUB likes type1. I don't think anything likes type1.

If you are doing camcorder footage, then it's easy. Capture in chunks. Say 20-40 minutes, find a good break point and stop. Then backup the tape and capture again. You can then trim and join the segments with no noticeable effects.

[Smells_Like_Feet]

Yes WinDV will allow you to specify the DV type you capture. As far as editing, I have been unable to get VirtualDub to accept any of my DV footage. That could be because I capture and work with only Type 1 DV. For editing (simple cutting out of commercials like you request) I have only used Ulead Videostudio. As far as adding effects and transitions, I haven't tried much of that yet and don't know what software to recommend.

Give WinDV a try and let us know if the different DV types make a difference with AV synch on your system too. Good luck.

- Smells_Like_Feet

[racerxnet]

From some of the sticky's I've read, the problem can stem from the stability of the audio card installed on the system. I think that Direct X diagnostics checks the stability of your sound card. You might also check for a utility which can do this for you. It may not be the answer you are looking for, but just a suggestion. Other things are to tweak the system for maximum performance.
MAK

[Almost Human]

Smells_Like_Feet you hit the nail on the head, WinDV works great. Thanks!

I can now backup all my commercial video tapes to DVD with no Macrovision (alternating light-dark) intrusion.

VCR - Sony DV8 passthrough - WinDV - TMPGEnc - TMPGEnc DVD Author - HP 200i. Can't tell the difference between the two.

Thanks all!

[Smells_Like_Feet]

Great to hear it worked for you. It still does not make sense, but I know what works for me (and now you).

-Smells_Like_Feet