Lines in render

DaveF wrote on 5/12/2003, 11:58 AM
I've seen various posts discussing this problem, or very similar problems.

I'm seeing picture lag on pans and shots with lots of vertical motion. It looks kind of like someone is projecting my footage on venetian blinds, then moving the blinds. Imagine you did that, then moved every other band of the venetian blinds about an inch apart. That's what the picture looks like.

I don't see the problem when editing in preview, only when rendering, either to AVI or MPEG2.

This is a 6 minute video with a lot of motion tracking envelopes, dissolves and speed changes.

If I randomly grab a few media clips that look bad in the project, then put them on a new timeline and print to tape, they look fine.

Some of the footage is from miniDV, some from VHS through a DAC-2 encoder.

All footage captured "lower field first" and project set to "lower field first."

Any gurus have any suggestions?

Comments

Former user wrote on 5/12/2003, 12:31 PM
You are probably watching this on your computer right?

This is interlacing, normal in a TV signal. A computer is progressive so when you watch a full rez video on your computer you see the interlacing.

Interlacing is caused by the fact that each video frame is actually made up of two fields which are spatially 1/60th of a second apart. If you watch this on a normal TV, you will not see this. If you are only going to watch this on your computer, search for information on deinterlacing your video.

Dave T2
DaveF wrote on 5/12/2003, 1:04 PM
Sorry, I guess I left out an important piece of information.

The banding/combing/flickering is visible on an external screen, after doing "Print to tape" or burning a DVD. I don't think this is an interlacing issue.

If I watch the rendered AVI or MPEG file on my computer, I DO see the problem. The only way I DON'T see the problem is while previewing, ie playing from the timeline. And, of course, if I take several files and print them to tape outside of this particular project, their is no problem.

Thanks

SonyDennis wrote on 5/13/2003, 3:12 PM
Try setting the Video Preview to "Good" or "Best" -- now do you see the problem during preview? I suspect you turned off "Deinterlace method" in project properties.
///d@
BillyBoy wrote on 5/13/2003, 4:30 PM
Dennis, if you got a minute... which do you feel is superior and why (blend or interpolate) as far overall deinterlacing effectiveness?

How much does it really matter? I read somewhere and it says the same thing in Vegas online help that the blend method is better suited for video that doesn't have a lot of motion and is in fact better for bringing out detail while interpolate is generally better for videos with lots of fast action.

And a couple $64 qustions regarding interlacing itself.

Am I correct that you should select 'none' if the video is only going to be played off a computer?

And if you burn a DV that will be played off a set top DVD player, and the data stream obviously comes from the DV player and isn't broadcast, how does interlacing come into play or does it? I've seen so-called 'experts' on various web sites jump all over the map on this.

Your thoughts?
DaveF wrote on 5/15/2003, 8:18 AM
Video preview was set to "Auto." Deinterlace was set to "Blend Fields."

Not seeing the image flaws in preview is a minor part of the problem. Any suggestion on how to get rid of the image flaws?

Thanks,
Dave
Dezine wrote on 5/15/2003, 11:25 AM
Have you tried using supersamling or educe interlace flicker?

Dezine
bf wrote on 5/15/2003, 8:23 PM
I'm having the same problems in both 3.0 and 4.0. Yes, I've tried reduce interlace flicker and resampling. I too, would love to know how to solve this problem. It occurs almost everytime I use track motion or modify the zoom on a video clip.

Any help would be appreciated!

Thanks,

Bill
DaveF wrote on 5/16/2003, 1:18 PM
> I'm having the same problems in both 3.0 and 4.0. Yes, I've tried reduce interlace
> flicker and resampling. I too, would love to know how to solve this problem. It occurs > almost everytime I use track motion or modify the zoom on a video clip.

Now isn't that interesting? I had th problem when I tracked motion and zoomed. Not on the portion that had the lines in it, but the video was on the same track, although towards the beginning of the timeline.