.Mpg "Flickering" Problem

[thisguyknows]

I'm using Sony Vegas 12 64bit. I have a video of a dance concert that I've edited. The footage in the timeline looks fine but every time I try to render it as an mpg, the lighting in the video flickers, suddenly becoming brighter, darker, flashing, etc.

I've tried various mpg settings to no avail. I tried rendering as an AVI, and that seemed to work better, but once I put it into Encore (CS4) and compressed it, I had the same problem.

I've been doing this kind of project for years and I've never seen this before. I am at a total loss. Any ideas?

[poisondeathray]

Try disabling GPU acceleration - it's know to cause many rendering problems with vegas (and it hasn't been available in vegas "for years", it's relatively new - maybe that's why you haven't seen this before)

[thisguyknows]

Thanks for your reply. I have already disabled GPU acceleration, and that fixed the problem of frames blacking out and text disappearing, but this little anomaly remains.

I seem to have reduced the issue by switching the render from interlaced to progressive, but the light flickers are still there every once in a while. Anyone have any other suggestions for mpg settings?

I'll try to get a clip of what I'm talking about uploaded, but I'm on my way out the door right now.

Thanks again

[jagabo]

Yes, before and after clips would be useful.

[thisguyknows]

Ok, you're gonna call me crazy, but once I posted it to youtube, the flashes didn't show up.

Am I losing my mind? Is it just a playback problem on my PC?

You may be able to see a subtle little one in this clip, but the major ones which are readily apparent on my PC do not show up here.

It should be noted that any other timeline I render under these settings does NOT produce this effect. I suspect it has something to do with the compression's attempt to deal with the generally low lighting in the piece. But I don't really know. I'm starting to think it's ghosts.

http://www.youtube.com/watch?v=TksCTmkIxas

[jagabo]

Youtube reencodes everything so we can't tell what your video really looks like from that. You should upload a sample directly to this forum. The forum accepts up to 100 MB files. Look at the Quick Reply box below this post. Use the Upload Files / Manage Attachments button below the edit box when you post a message.