dvd render is ‘wavy’

[Tudor Applen]

I’ve experienced the wavy phenomena as well. For me, it happened when I converted from Lossless to Apple ProRes HQ, which changed the width of my picture from 720 to 729. That maybe fixable, but I did something else rather than try to fix it – so I don’t know. The wavy thing happened in the same area though, just on the moving masks. Maybe not the same issue, and certainly not a solution, but thought I’d mention it.

[Aharon Rabinowitz]

This is a new one to me, but maybe… maybe… try taking your final comp and then nest it in a new comp.

Maybe AE won’t see the masks anymore? When you precompose and nest, AE looks at it as footage instead of a comp, more or less.

It shoudldn’t help… but then, it shouldn’t be happening at all. So who knows?

Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
Creative Cow After Effect Podcast
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[Kevin Camp]

do you see the issue when the dvd is played on a standard tv, a computer or both?

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Kelly Johnson]

both… but here’s something that might help from the Lynda.com training videos:

the original AE file with the masks, select the Composition Settings and click the “Preserve frame rate when nested or in render que.”

That will force the nested comp to retain it’s original fps so that the mask keeps up with the footage.
(Maybe this is akin to what Aaron mentioned?)

Also, you might know this but if you set the frame rate to 59.94 and use the arrow keys to move through the comp, you get a better indication of what a render will look like. That’s all some math shit related to the pulldown being mixed with stuff created at 29.97

If that doesn’t do anything, then setting the Stretch on the layer to multiples of 80% might. 80% seems to be the magic number. If you have Twixter, it’s based on Speed which the numbers are as in the screen capture attached.

Now, those things were from AE 7 so I’m guessing they may still work the same in CS3.

[Kevin Camp]

are you using mixed frame rate footage or mixed frame rate comps in a final comp…? not that you can’t do it, i’m just trying to understand your last post being primarily concerned with frame rates….

the preserve frame rate when nested option would be used if you wanted to, say, have a stop frame animation that was at 5fps look like it was at 5fps even when you composited it in a 29.97 comp with other footage or animations…. otherwise the 5fps comp movement would get recalculated at 29.97 and look much smoother.

the 59.94fps comp is a good way to work with 29.97 interlaced material, particularly for keying and motion tracking, because it allows you to see the second set of fields when ae is set to separate fields as you work with the footage. then, at render, you can render back to fields (note, if you weren’t going to render back to fields, or to 59.94, you wouldn’t need to see the second set of fields).

time stretch 80%, starts sounding like you are dealing with 23.976fps footage… 23.976fps is 80% the speed of 29.97fps… are any of your footage or comps 23.976?

i’ve seen waviness in renders when footage was scaled improperly (with fields left in prior to scaling). if you are going to dvd, your final rendered comp should be 720×480. if your comp was 720×486, the software may have scaled that to 720×480 and that could account for some problems.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Kelly Johnson]

Thanks for that post. It pulled some strings. The original was shot HD 24p on a VariCam, then converted, pulled-down, and something else.

Seems like there was just too many conversions along the way. The final QT file we have is 720×480, Animation, millions of colors but it does show as interlaced in the QT player and various programs.

Trying to set the field order either way, blending etc doesn’t seem to matter..it either gets terribly interlaced or the wavy thing happens.

I think we just need to get the original stuff before all the converting happended!

[Kevin Camp]

ae can effectively remove the pulldown, if the original 24p footage had not been edited with the pulldown… so if you had individual shots that were 24p with a pulldown that were effected, then you can use the interpret footage settings to remove the pulldown (guess pulldown usually works), giving you just the progressive frames. you can also count the whole and split frames to determine the cadence by advancing frame by frame for several frames.

then, in your comps, you should be able to adjust the frame rates to to 23.976 which will remove the duplicate frames (every 5th should be a duplicate at 29.97). if all you comps are 23.976, you have a choice, either render as progressive and burn a progressive dvd, or render with fields (ae will add the pulldown) and burn a normal dvd… if possible i would try to go the progressive route.

if the footage has been edited with the pulldown in place, you have a mess on your hands. you won’t be able to remove the pulldown (because the order of progressive (whole) frames and interlaced (split) frames won’t be consistent). unless you split the piece back into individual shots, remove the pulldown for each shot, then reassemble it… ouch.

your waviness on some of the masks may be due to the interlacing (pulldown) that was not removed prior to effecting… i could see how that may create some issues, even with just masks.

i’ve had to deal with several 24p/pulldown problems before… now when any photog/editor/producer mentions 24p on a project that may be coming my way, i try to school them pulldowns and a 24p workflow. actually i try to talk them out of it, since i’m in tv, i tell them everything if it has to get to 29.97 at some point, it might as well be the start. but creating a progressive dvd is a valid reason to shot 24p…

i still find it a little interesting that you don’t see the waviness in the original render or ram preview… so maybe your fix will be a little easier than dealing with pulldown issues, hopefully.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Kelly Johnson]

Thanks Kevin, that was a great explanation and is just what happened… editing and pulldown mixed with converting etc and other stuff.

That will help me in the future for sure!