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eukls
Horizontal Lines
on Jun 8, 2006 at 4:38:37 pm

I'm shooting with a Sony VX2100, capturing via firewire with Premire Pro 1.0,
outputting to an .avi file. When I play the avi file some of my videos have horizontal lines around edges of subjects in the video. For instance a commercial for a tanning salon, the models arms have the lines along the outline. This happens on the desktop monitor and 36" lcd tv with RGB input. There are several projects like this. The tanning footage was provided by another company, so I don't think it is the camera.
Any ideas, Thanks in advance


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John Applegate
Interlacing issue?
on Jun 8, 2006 at 6:39:16 pm

Hello eukls,


Are the horizontal lines always present around the subjects or only when they are moving?


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eukls
Horizontal Lines
on Jun 9, 2006 at 3:40:05 pm

The lines are when a subject is moving.


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John Q
Re: Horizontal Lines
on Jun 9, 2006 at 8:25:12 pm

That's a field order problem. Standard video is interlaced, separating the odd and even lines in different fields combining into a single frame. Your camcorder also has a progressive mode, capturing all lines to a single frame. If you mix up the field order, you get the venetian blind effect.


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John Applegate
Things to try
on Jun 9, 2006 at 9:25:42 pm

Sounds like interlacing. I'm not familiar with Premier pro, but if it does not provide access to framing order (aka John Q's suggestion) AND does not provide a deinterlace capability, AND you are really attached to the footage that you took, then you may wish to preprocess the footage before dragging it back into APP. There are a number of websites out there describing how to do this. I found the article at:

http://www.100fps.com

particularly useful. The VirtualDub tool (free) described there is good and can be downloaded at http://www.virtualdub.org. I have used VirtualDub with some success to deinterlace fast moving sports videos shot by others. It does introduce some minor fuzziness, but if the interlacing is really bad, you may decide to live with it... Also for what it is worth, I have had better luck with the Alparysoft filter (http://www.files32.com/info36289.htm) than the Gunnar Thalin Deinterlace-Smooth filter that is described in the 100fps page.

You will have to experiment a little bit with filter configurations, but you can often do a reasonable job cleaning up some of these framing artifacts.

If your camera does have a bonified progressive capture mode (e.g. 24P, etc.), as John Q suggests it does, then you may wish to consider using that mode in the future to capture.

Good luck and let us know how you come out!


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Troy III
Re: Horizontal Lines
on Jun 17, 2006 at 1:01:41 am

It's definitely an "interlacing" problem.
If this happens especialy with footage you didn't capture. The problem is caused by wrong/different field order settings. Treat your project as "progressive" it might make them go away, because if you set a different field order (from "upper first" to "lower first" or vice versa), you might cause the second footage to show as interlaced while correcting the first...


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