Reducing Staircasing/Zipper Effect from Deinterlaced Video at DVinfo.net

Kin Kwan · July 12th, 2004, 11:02 PM

Hi, I know there are some expensive applications out there that can achieve this effect, but I was wondering if there are free plugins/softwares/filters that can reduce/eliminate the staircasing effect from deinterlaced videos. Maybe something for Virtual Dub or After Effects?

I would buy those expensive programs...but I'm kind of broke since I got a copy of Premiere Pro. :/

Frank Ladner · July 13th, 2004, 08:03 AM

Kin: Hi! If you're not shooting deinterlaced (ie. frame mode, or one of the digital effects like in Sony cams), then here is a well-known trick you can try(requires no plugins):

(This is for After Effects, but Premiere Pro may be able to do it.)

#1: Import two copies of your footage.
#2: Place them on two separate layers, one on
top of the other.
#3: Set one clip to Lower Fields and the other to
Upper Fields.
#4: Set the opacity of the top layer to 50%.

#5: Render out with the Deinterlace (no fields) option.

This will give you more resolution per frame than just deinterlacing by doubling the fields. (I think 25% more resolution.) ... and since it's not field-doubled, then you should have less stair-stepping in your footage.

Hope this helps!

Kin Kwan · July 17th, 2004, 10:49 PM

Hey Frank, thanks for the reply!

I've tried many deinterlacing methods, including the one you mentioned above, and I would like to share some of the results:

The original image:
http://eternalabyss.com/images/KinsF...t/Original.jpg

Area Based Deinterlacer (Virtual Dub filter):
http://eternalabyss.com/images/KinsF...Deint/Area.jpg

MAP Deinterlacer (Virtual Dub filter):
http://eternalabyss.com/images/KinsFolder/Deint/MAP.jpg

Smart Deinterlacer (Virtual Dub filter):
http://eternalabyss.com/images/KinsF...eint/Smart.jpg

Discarding a field and then resizing back to 720 x 576:
http://eternalabyss.com/images/KinsF...nt/Discard.jpg

Blending the fields:
http://eternalabyss.com/images/KinsF...eint/Blend.jpg

After Effects Method:
http://eternalabyss.com/images/KinsF...nt/AfterFX.jpg

I prefer interpolating because it produces a full frame and there aren't any motion blur, but most of them produce a lot of jaggies. The After Effects method produces a "ghosting" effect, similar to the blending method, but it's less noticeable.

It'd be nice to find a filter that can do anti-aliasing on those jaggies. Hit me up if ya'll know of any!

David Warrilow · July 20th, 2004, 05:21 PM

Hi,

have you tried the 'TomsMoComp' filter for AVISynth? Once you have the filter and have made a (very) simple script for avisynth, you can open it in Virtualdub and run it from there. You can even add sharpening filters/color correction/smoothing from there too and see the results right there before rendering.

I've compared the results from this deinterlacing filter to things like MagicBullet/Fields kit/DVFilm and the 'instant sex' method (if that's the chic name for it) described for AFX above and in my opinion it's better than all of them. And it's about 20 times faster. Best yet, it's free - you can't lose giving it a try.

I've not enlarged the deinterlaced DV footage to see how it holds up at higher rez but for SD sizes I think it's awesome.

Others of course will have their own results and experience - but avisynth/VDub and the related filters seem to be very underused resources for this sort of work.

Best,

DW.

Cosmin Rotaru · July 21st, 2004, 03:41 AM

Kim, this I like best:

"MAP Deinterlacer (Virtual Dub filter):
http://eternalabyss.com/images/KinsFolder/Deint/MAP.jpg" :)

July 12th, 2004, 11:02 PM	#1
Kin Kwan Regular Crew Join Date: Jul 2004 Location: Plano, TX Posts: 120	Reducing Staircasing/Zipper Effect from Deinterlaced Video Hi, I know there are some expensive applications out there that can achieve this effect, but I was wondering if there are free plugins/softwares/filters that can reduce/eliminate the staircasing effect from deinterlaced videos. Maybe something for Virtual Dub or After Effects? I would buy those expensive programs...but I'm kind of broke since I got a copy of Premiere Pro. :/ __________________ Kin Kwan

July 13th, 2004, 08:03 AM	#2
Frank Ladner Major Player Join Date: Aug 2003 Location: Poplarville, MS Posts: 453	Kin: Hi! If you're not shooting deinterlaced (ie. frame mode, or one of the digital effects like in Sony cams), then here is a well-known trick you can try(requires no plugins): (This is for After Effects, but Premiere Pro may be able to do it.) #1: Import two copies of your footage. #2: Place them on two separate layers, one on top of the other. #3: Set one clip to Lower Fields and the other to Upper Fields. #4: Set the opacity of the top layer to 50%. #5: Render out with the Deinterlace (no fields) option. This will give you more resolution per frame than just deinterlacing by doubling the fields. (I think 25% more resolution.) ... and since it's not field-doubled, then you should have less stair-stepping in your footage. Hope this helps!

July 17th, 2004, 10:49 PM	#3
Kin Kwan Regular Crew Join Date: Jul 2004 Location: Plano, TX Posts: 120	Hey Frank, thanks for the reply! I've tried many deinterlacing methods, including the one you mentioned above, and I would like to share some of the results: The original image: http://eternalabyss.com/images/KinsF...t/Original.jpg Area Based Deinterlacer (Virtual Dub filter): http://eternalabyss.com/images/KinsF...Deint/Area.jpg MAP Deinterlacer (Virtual Dub filter): http://eternalabyss.com/images/KinsFolder/Deint/MAP.jpg Smart Deinterlacer (Virtual Dub filter): http://eternalabyss.com/images/KinsF...eint/Smart.jpg Discarding a field and then resizing back to 720 x 576: http://eternalabyss.com/images/KinsF...nt/Discard.jpg Blending the fields: http://eternalabyss.com/images/KinsF...eint/Blend.jpg After Effects Method: http://eternalabyss.com/images/KinsF...nt/AfterFX.jpg I prefer interpolating because it produces a full frame and there aren't any motion blur, but most of them produce a lot of jaggies. The After Effects method produces a "ghosting" effect, similar to the blending method, but it's less noticeable. It'd be nice to find a filter that can do anti-aliasing on those jaggies. Hit me up if ya'll know of any! __________________ Kin Kwan

July 20th, 2004, 05:21 PM	#4
David Warrilow Regular Crew Join Date: Apr 2003 Location: Brisbane, Australia Posts: 106	Hi, have you tried the 'TomsMoComp' filter for AVISynth? Once you have the filter and have made a (very) simple script for avisynth, you can open it in Virtualdub and run it from there. You can even add sharpening filters/color correction/smoothing from there too and see the results right there before rendering. I've compared the results from this deinterlacing filter to things like MagicBullet/Fields kit/DVFilm and the 'instant sex' method (if that's the chic name for it) described for AFX above and in my opinion it's better than all of them. And it's about 20 times faster. Best yet, it's free - you can't lose giving it a try. I've not enlarged the deinterlaced DV footage to see how it holds up at higher rez but for SD sizes I think it's awesome. Others of course will have their own results and experience - but avisynth/VDub and the related filters seem to be very underused resources for this sort of work. Best, DW.

July 21st, 2004, 03:41 AM	#5
Cosmin Rotaru Major Player Join Date: Feb 2003 Location: Romania, Timisoara Posts: 453	Kim, this I like best: "MAP Deinterlacer (Virtual Dub filter): http://eternalabyss.com/images/KinsFolder/Deint/MAP.jpg" :) __________________ Cosmin Rotaru