ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

Reducing "moire" from striped clothing

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Christian Wheel
Reducing "moire" from striped clothing
on Jan 26, 2011 at 7:02:01 pm

Got some footage back from a big expo, and have been asked to edit down a speech that a Fortune-500 company's CEO delivered. I watched in horror as he walked out to the podium wearing a suit with very LOUD pinstripes. Those pinstripes are shimmering (moire?) in the footage as he moves around. Any ideas on how to reduce this effect?

Thanks in advance...


Return to posts index

Spencer Tweed
Re: Reducing "moire" from striped clothing
on Jan 26, 2011 at 7:25:11 pm

Yeesh. I hate moire!

I'd need a little more info to help you out. For example, is the moire coming from After Effects or the medium it was loaded onto? Was this a defect in the camera itself? If you are down-sizing the footage in AE you will sometimes get moire.

First nail down where the problem is entered it, and then you can find the solution (or ask).

- Spencer


Return to posts index

Christian Wheel
Re: Reducing "moire" from striped clothing
on Jan 26, 2011 at 7:30:31 pm

It's coming from the DV camera it was recorded on. I can see it even when the camera is hooked up to a monitor.

Thanks


Return to posts index


Dave LaRonde
Re: Reducing "moire" from striped clothing
on Jan 26, 2011 at 7:37:21 pm

[Christian Wheel] "It's coming from the DV camera it was recorded on"

Ugh -- DV. Is this something you wish to undertake on your own, or is it something requested by the client?

The reason I ask is this: I can only think of one way to do it, which is to create an animated mask around the subject, then copy the mask to either a duplicated layer or an adjustment layer, to which has been added a tasteful amount of horizontal blur.

That could be a lot of work. Whose nickel will it be on?

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index

Olin Padilla
Re: Reducing "moire" from striped clothing
on Jan 26, 2011 at 8:34:22 pm

Beware that whenever you reduce moire in post, there is a good chance it will resurface with your eventual compression and/or scaling.

Best case scenario, you will be able to isolate the suit without having to roto, and then use Dave's technique. Another cheap fix is to try adding noise. Again, the moire patterns might return when scaled or compressed.


Return to posts index

Walter Soyka
Re: Reducing "moire" from striped clothing
on Jan 26, 2011 at 9:02:02 pm

[Christian Wheel] "It's coming from the DV camera it was recorded on. I can see it even when the camera is hooked up to a monitor."

If the moiré is caused by DV's chroma subsampling (usually appears purple/green-looking), you might be able to reduce it by smoothing the chrominance channels. Use the Channel Combiner [link] effect (set to RGB - YUV), then Channel Blur [link] (G&B channels only), then Channel combiner again (this time, YUV - RGB).

If the moiré is luminance, though, there's not really anything you can do aside from Dave's suggestion of masking and blurring.

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


Christian Wheel
Re: Reducing "moire" from striped clothing
on Jan 27, 2011 at 1:14:42 am

Thanks for the answers guys. Nobody asked me to "fix" it because I don't think anyone's been made aware there's a problem. It just looks terrible IMO, and I suspect if I just make the normal NLE edits I was brought on to make, they will send it back with a "why the hell does this look so bad" note attached.

Perhaps on delivery of the edited version I will include a preemptive disclaimer attributing the effect to his choice of wardrobe.

It does seem to be luminance based, and I tested Dave's suggestion on a couple of frames and it works, but that's incredibly tedious and unless they pay for it, it's really "not my job" at this point. :)

Thanks for the help...


Return to posts index

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