audio video sync problem

ngurah wrote on 2/15/2005, 1:27 AM

Hello,

I captured AVI form HI8 using analog card for 15 minutes. I use Huffy codec to compress A/V during capture.and set YUY2 color space format. The program I used to capture is MSP Pro 70. on Win XP pro SP 2

When I Imported the video into MSP 70 and Adobe premiere 70, I found no problem with audio and video. All video will have the same length with audio on both Video editing program .I rendered the video then " Very well Done " No problem at all

But when imported into Vegas 5, i found syc problem with audio and video. It seem the audio has 12 frame longer than video. I did not Cut the frame, but change the plybact rate instead. I try to make change on playbackj rate to the audio and make shorter 12 frame to sync A/V. It works, But when I captured into 10 minutes, it should be shorter about 14 frames to make it sync
Confusing huh !

But I am tired to make shorter every clips . why it can be happened ? Any suggestion

Thank you for the answer

Ngurah Agung
www.artinicottage.com

Pent III 1 Ghz
Win XP Pro SP2
HD 120 G

Comments

jbrawn wrote on 2/15/2005, 10:17 AM

I'm not sure why it is working correctly with MSP 70 and Adobe premier 70. It may be that those programs automatically force the audio to fill the same time as the attached video.

The two bullet-proof ways to get HI8 into Vegas are: 1) Get a Digital-8 camcorder and play the HI8 tape into the PC using firewire. 2) Get a Mini-DV camcorder with passthrough, or an analog to DV converter box like a Canopus ADVC-110 and capture to the PC via firewire.

Good Luck,

John.

johnmeyer wrote on 2/15/2005, 10:53 AM

I just spent several hours yesterday working on this same issue. I will take a guess that your capture card is ATI and that you are using the Multimedia Center (MMC) to do the capture. That software works great when capturing using the ATI codec (for their "TiVo" capture) or when doing MPEG-2 capture using their codec. However, it is completely useless and bug ridden when used with external codecs. The Huffyuv site even says you can't use the Huffyuv codec with the ATI software.

The solution -- if you want to still capture using the analog card rather than use a DV passthrough as jbrawn suggests -- is to use different capture software. The Virtualdub capture works great. I use the latest version of VirtualDub (1.5.10) for most things, but I keep a separate, slightly older, slightly hacked version that has specific capture enhancements, including a timer to start/stop capture at preset times.

The Huffyuv settings that work well with Vegas are:

YUY2 compression method: Predict left (fastest)
RGB compression method: Predict left/no decorr. (fastest)
Field Threshold: 480 lines
Enable full size output: checked
All other items: unchecked

In VirtualDub, I set capture format to:

Format: 720x480

(I live in NTSC-land)

I tried some of the higher quality settings, but Vegas couldn't play the files in real time, and the file sizes got larger (the files are 2x the size of DV files to begin with).

As to why your existing capture works in Premiere and not in Vegas, I would assume that there is some sort of behind the scenes fixup going on. I'd sure look long and hard at the results to make sure the audio is in sync.

So, bottom line: If you capture with VirtualDub, you won't have the audio "shrinkage" problem; if you capture with ATI software, you will.