FORUMS: list search recent posts

removing moire

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
alan pover
removing moire
on Sep 2, 2010 at 5:59:36 pm

Hello. I am looking for a way to remove some moire pattern on a suit. I haven't found the perfect solution yet. The closest thing I've found is this:

http://forums.creativecow.net/thread/2/926421#955659

"Sometimes the moiré only occurs in the color-channels (green/purple moirés)
Check if that's the case using the channelcombiner rgb->yuv and check the first (R) channel.
Sometimes you need very aggressive medians or blurs to get rid of those, but you can recombine the original Luminance back in using a layer-mode of luminosity."


I don't really understand what he meant. I tried applying the channel combiner filter. I did check the first R channel and I can see the moire there, and I applied fast blur it. But I can't recombine them together using luminosity mode. Thats where I got lost. Does anyone understand what he meant?

And then, in the same thread, someone mention a preset which sounds very promising. But sadly the link doesn't work anymore.

http://www.curiousturtle.com/training/presets/moire reduction.zip

Is there any other way to get rid of the moire.

Thanks


Return to posts index

Rezi Bout
Re: removing moire
on Feb 21, 2014 at 12:03:31 pm

Signed up to creativecow JUST to reply to you comments Dave.
You are all over creativecow, always bashing people. Stop please.
Why always so negative bro? Relax and actually contribute


Return to posts index

Austin Hill
Re: removing moire
on Jun 20, 2016 at 10:04:51 pm

He's so smug. Oh really? Re-shoot? If we could "re-shoot" we wouldn't be in this goddamned thread.


Return to posts index


Walter Soyka
Re: removing moire
on Sep 2, 2010 at 7:00:30 pm

[alan pover] ""Sometimes the moiré only occurs in the color-channels (green/purple moirés)
Check if that's the case using the channelcombiner rgb->yuv and check the first (R) channel.
Sometimes you need very aggressive medians or blurs to get rid of those, but you can recombine the original Luminance back in using a layer-mode of luminosity."

I don't really understand what he meant. I tried applying the channel combiner filter. I did check the first R channel and I can see the moire there, and I applied fast blur it. But I can't recombine them together using luminosity mode. Thats where I got lost. Does anyone understand what he meant?"


In loose terms, the advice in that post is to process in YUV (essentially one channel of brightness and two of color) instead of RGB (three channels of color values, with brightness of the image distributed throughout).

The basic idea is to reduce moiré without reducing sharpness by blurring the chrominance channels, but not the luminance channel. This only works when the moiré is not present in the luminance channel. From what I can tell from that thread, the curiousturtle preset uses this method.

If you saw no moiré in the R channel (which is really the Y or luminance channel, thanks to Channel Combiner), then you could use a Channel Blur on the UV or chrominance channels (GB to AE, after Channel Combiner) to reduce the moiré.

However, since you DID see moiré in the luminance, you are out of luck.

As usual, Dave's advice is best: reshoot. Your other alternative is to rotoscope and blur/median, but I doubt this would look quite right.

I have reduced shimmering before in very simple shots with a freeze frame, masking, and tracking -- but that'd be completely impractical with clothing in interview footage.

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog - What I'm thinking when my workstation's thinking
Creative Cow Forum Host: Live & Stage Events


Return to posts index

Diego Llamazares
Re: removing moire
on Aug 30, 2014 at 12:58:38 am

I have recently tried this moire removal preset for Neat Video and it worked wonders for me.








http://www.noiseproofpro.com


Return to posts index

Lloyd Claycomb
Re: removing moire
on Jun 13, 2012 at 6:22:03 am

I have a simple trick to at least mitigate the effects of morié. I understand that sometimes reshooting isn't an option. I have used this with positive results on shirts with lines.

In After effects simply add 2 adjustment layers above your problem footage. Add the "median" effect to each one. Set the blend mode of one to "color" and the other to "luminosity." Play around with your radius settings on the effect for each one.

Depending on the type of morie that's happening, you may not need one or the other layers, but then again you could need both. Massage the numbers until your morié is lessened.

Unfortunately it probably won't go away entirely and you'll still hate the footage, but if you do your A/B comparisions, you most likely will like your "B" results better than the original.

If you're problem is in an isolated part of the shot (e.g. a person's shirt), then you'll need to isolate the problem area (I use rotobrush to quickly fix shirts with good skin contrast) and apply the Median effected adjustment layer(s) to JUST the problem area.

And, with all roto, have fun!


Return to posts index


Lloyd Claycomb
Re: removing moire
on Jun 13, 2012 at 6:38:44 am

By the way, I realize this post is old, but the problem still happens today. Before finding something that worked for me, I did a search and this was the first thread I could find on the subject, so I figured if I found it two years later, somebody else with the same problem probably will too and it would be nice if this thread at least gave a partial solution.

Hopefully new cameras will make this post irrelevant someday soon, but until there, folks, here's weak, albeit working Band-aide to help you through.


Return to posts index

Aaron Davis
Re: removing moire
on Aug 21, 2012 at 12:20:22 am

Hey just wanted to chime in with something that I think helped. I shoot on a DSLR and then transcode to ProRes right after I take it off the card. So I was trying all these methods on the ProRes file and the moire was reduced but still pretty bad. Then I tried going back to the original H264 file and used the method of an adjustment layer set to luminosity with median effect in AE and it worked a lot better than anything else. This makes sense because moire is a problem with too much detail and when you go back to a more compressed codec I would assume there's less detail in the file.
Also helps if you don't scale the video at all, that increased moire for me.

-Aaron HD


Return to posts index

Michael Glover
Re: removing moire
on Oct 1, 2012 at 6:01:50 pm

Moire Fix Option:
I just had a shirt going crazy in a feature film edit. No chance to reshoot. I took the roto brush tool in AE CS6 and after putting only the shirt on a top layer, I added gaussian blur at low level (number 2). Worked perfectly. Looks very natural.


Return to posts index


Brett Nelson
Re: removing moire
on Dec 13, 2013 at 7:35:43 pm

This is one of those times I really appreciate the Cow! The slight Gaussian blur on a suit jacket saved me in a last-minute crisis...an executive's greeting that had to go out within a couple of hours. I didn't see the problem until it went to YouTube. I duped the layer and did a garbage matte around the suit (It was green screen, so I could cut the matte fast and loose). Below the neck was a slight bit soft, but the face was sharp and the clip looked good.

Thank you!

Brett


Return to posts index

Peter Cutler
Re: removing moire
on Apr 17, 2013 at 9:03:55 pm

I want to second the roto approach. If you just have a suit or clothing that's the issue, roto out the suit or fabric, then play around with desaturation, blurs, channel mixing, etc. -- this can be very effective


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]