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DeFlicker filter problem

Posted: Mon Nov 29, 2010 9:29 am
by vidjim
Can anyone help me figure out what I am missing in trying to use the DeFlicker filter for VirtualDub. I followed instructions in attempting to remove flicker from an old 8mm video transfer. After saving/processing the file I find no difference in the pre-process vs. processed files. They look the same with no decrease in flicker.

Re: DeFlicker filter problem

Posted: Mon Nov 29, 2010 9:37 am
by admin
Post a link to an unprocessed source sample.

Re: DeFlicker filter problem

Posted: Mon Nov 29, 2010 3:17 pm
by vidjim
Never done that before.

Re: DeFlicker filter problem

Posted: Mon Nov 29, 2010 4:32 pm
by admin
Sorry to hear that.

Re: DeFlicker filter problem

Posted: Mon Nov 29, 2010 8:47 pm
by vidjim
I am attempting to deflicker 8mm film shot at 24fps and video taped at the standard 30 fps. I followed Jake Ludington's instructions (www.jakeludington.com/virtualdub/2007203_how to deflicker 8mm_movies.html) and also the "Filter How-To" at your site. The saved video still flickers the same as if the filter had zero effect.

Re: DeFlicker filter problem

Posted: Tue Nov 30, 2010 8:09 am
by admin
Please post a link to an unprocessed source sample.

There are various reasons that may cause the problem. One is that you are goofing up. Another is that the material may not be amenable to the filter because it does not have full frame flicker but rather "rolling shutter" flicker. So to help you properly, we need to see an unprocessed source sample. You can upload it to mediafire.com and post the link here.

Re: DeFlicker filter problem

Posted: Fri Dec 03, 2010 1:08 pm
by vidjim
Sorry for the delay. Here is the link to the video: http://www.mediafire.com/file/ye86qms8j ... %20Int.avi

Re: DeFlicker filter problem

Posted: Sat Dec 04, 2010 10:11 am
by Didée
Oh my. Samples usually shouldnt't be 1 GigaByte in size. One or two hundred frames would've been plenty enough ...

The flicker does have some of the mentioned "rolling shutter" characteristics. Maybe that's why VD deflick doesn't work very well.

I'm not used anymore to use VirtualDub filters, since Avisynth filtering offers so much more possibilities and control. The following was quickly thrown together:

http://www.mediafire.com/?1a8vwlh3kcfc6w0 (~31 MB, Avisynth script --and-- before-after video comparison)

It's sort of a compromise. Working frame-globally without localisation, the filter effect will be poor in this case. Working with strict localisation (per-pixel temporal processing), the flicker can be eliminated completely, but it gets very difficult to avoid severe artifacting in areas with motion. I've settled for a compromise that removes a major part of the flicker, and does rather little harm to moving parts.

Re: DeFlicker filter problem

Posted: Tue Dec 07, 2010 11:53 am
by vidjim
Thanks. It looks a lot better. I will try Avisynth for the rest of my old projects which run into many hours. Thanks again.