capturing avi sync problems

[jebero]

I've tried windv and now dvio and still get the same result using my passthrough camcorder with firewire. No matter how I capture by the end of the segment the audio and video are way out of sync. Still haven't gotten a viable answer...anybody? BTW virtualdub simply doesn't work with my camcorder with passthrough because of the firewire according to their site; something about no video for windows drivers. I'm really at a loss. What software will work with my setup? Thanks, this has been a great resource to a newbie like me. Jeff

[Tommyknocker]

What player did you use, and does it work with any players you own?

[jebero]

When I want to look at a file they open and play in windows media player. Nothing else works unless I transcode the file, then I have dvd players that will work but the sync problem remains.????

[FulciLives]

Well I have heard of other users of digital cams saying that they also sometimes have A/V sync problems when using analog pass through.

Although I admit this doesn't make a whole lot of sense on paper the reality is that most of these users have found that if they transfer to the computer using ScenalyzerLive as this program somehow manages to keep A/V sync.

- John "FulciLives" Coleman

[MpegEncoder]

I have noticed this problem also. It's not very noticable on short clips, but on full movies it's quite bad.

Here's my solution:

1) Capture with WinDV
2) Frameserve with VirtualDub (BUT, go to Frame Rate Control/Frame Rate Selection and select Change video frame rate to match audio)
This is a fractional change that will NOT affect encoding via your MPG encoder of choice.
3) Encode to MPG
4) Blah, blah, blah

This fixes the problem pretty well. Note that I usually frameserve with VirtualDub anyway to trim the part out that I don't want.

Hope that helps.

[jebero]

I also downloaded and tried scenalyzerlive with no success there either! For some reason it won't work with my setup--firewire card. It'll only capture still pictures. Sounds like I'll have to find out what frameserving is and how to go about it. EZ way for dummies? Thanks again

[MpegEncoder]

I also downloaded and tried scenalyzerlive with no success there either! For some reason it won't work with my setup--firewire card. It'll only capture still pictures. Sounds like I'll have to find out what frameserving is and how to go about it. EZ way for dummies? Thanks again

It is really easy,

Wherever you unpacked VirtualDub, there's a program called auxsetup.exe. Run that to allow VirtualDub to be a frameserver.

Then, run VirtualDub. Load the AVI that you want to serve. In the file menu, select "Start Frame Server". Pick whatever filename you want and go. From that point the filename that you selected is your source file for you mpeg encoder.

That's it.

[heyjjjaded]

I am in exactly the same boat as jebero. I still don't quite understand what frameserving is or exactly how to do it. I'm very new ... could we get some more help on this possible solution? Thank You!

[MpegEncoder]

I am in exactly the same boat as jebero. I still don't quite understand what frameserving is or exactly how to do it. I'm very new ... could we get some more help on this possible solution? Thank You!

What part don't you understand?

1) Install VirtualDub
2) Run auxsetup.exe (allows VirtualDub to act as frameserver)
3) Run VirtualDub
4) Load AVI file that you want to convert
5) Under file menu, click "Start Frame Server"
6) Pick a filename (any will do)
7) Start you mpegencoder (whatever you use) and open the filename that you just created for the frameserver (in step 6)
8) Start encoding

That's it.

The frameserver acts like a file.

[heyjjjaded]

I just haven't been doing this long enough to understand many of the basic terms yet. Is frameserving another term for editing video? Like trimming, splitting, or combining clips? Sorry ... thanks!

[MpegEncoder]

I just haven't been doing this long enough to understand many of the basic terms yet. Is frameserving another term for editing video? Like trimming, splitting, or combining clips? Sorry ... thanks!

No, frame serving is serving frames. In this case, VirtualDub acts as the frame server. When the mpegencoder needs a frame to work on, it asks the frame server for a frame (from the virtual file that's created). It processes that frame and then asks for another, until there are no more.

[sacajaweeda]

Frameserving gives your encoder a more stable/controlled feed of data and eliminates the need to re-save your processed (edited) clips to a new file on your hard disk.