ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

Twixtor Warping on 210 fps 3D footage (pictures)

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Nick LyonsTwixtor Warping on 210 fps 3D footage (pictures)
by on Sep 5, 2011 at 4:34:52 pm

So realizing I want my 3D footage to slow down a considerable amount I rendered the slowmo part at 210fps (the rest of the frames are at 30). When I bring it into AE and add Twixtor Pro, I set the frame speed as 30, and then ramp the speed down to 25% (ideally I want 10%, but that gets worse). I get warps on the background image, but luckily not the foreground train. See picture below:

(picture here http://imgur.com/k7AtY )

I heard you can use masks to tell twixtor what to effect and what not to effect. I tried adding a mask using (FG Setting 1) a comped sold layer. After messing around with it for a bit I couldn't get it to work in the slightest. I roto'd the train using a red layer mask (comped) and set that as FG1. The only thing that happened then was the whole picture was blown out. See image:

http://i.imgur.com/y2HMY.jpg

So I imagine my solution is within the masking, but I don't know how to use them, and I can't seem to find a decent tutorial on it anywhere.

Any idea for a possible solution?

Thanks!


Return to posts index

Walter SoykaRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 5, 2011 at 8:24:47 pm

[Nick Lyons] "I heard you can use masks to tell twixtor what to effect and what not to effect."

Not exactly. You can use masks or splines to guide Twixtor's motion estimation. In effect, you can animate a mask over time to tell Twixtor "the pixels under this mask at frame 0 are supposed to be the same as the pixels under the mask at frame 1."

But let's back up a bit first. Twixtor Pro allows you to separate your image into one background and three foreground channels. You can improve your motion estimation (and reduce your gloppiness) considerably with this feature alone. Render out an object buffer pass for your train. Use this as the FG1 matte, and use its inverse as the BG matte. (You may need to finesse the edges of the matte for better results.)

If you want to use spline guidance with AE masks, In the case of your train, you could use an open mask to show Twixtor the edge of the train. Set Twixtor's output to Source (NOT Twixtored output!), animate the open mask to precisely follow the edge, then turn the output back to Twixtored. Make sure to set the first mask and last controls for the correct channel (BG, FG1, FG2, FG3).

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

Nick LyonsRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 5, 2011 at 9:21:12 pm

Thanks for the response Walter. I've never used an Obj Buffer in Cinema so I wanted to walk through a couple details before I set my computer to render again, just ot make sure.

To do:

Add compositing tag to train
Assign it object buffer one.
Add obj buffer 1 to my multi pass

Questions:

Do I need to an external compositing tag to it as well?
Since I already have the rendered slowmo frames I want, is there a way to ONLY render the object buffer by itself?
Or if thats not possible, can I just lower my render settings to the absolute lowest since the object buffer isn't effected by AO/GI etc?

Once in AE take the obj buffer pass and add it to FG 1, the invert it (assuming like a mask?) then from there I'm guessing that will clean it up a bit.

Just wanting to make sure I do this the right way since that slow mo scene took 2 days to render :)

Thank you again


Return to posts index


Walter SoykaRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 5, 2011 at 9:36:09 pm

Your steps are look correct. No need for the external compositing tag (that's for exporting position and rotation information to AE or another compositor).

C4D can't render an object buffer by itself; it will want to calculate the entire RGB image. You can remove all lights and materials from your scene to speed this up significantly. You don't need to save image files or any of the other passes, so you can uncheck them all in your render settings; the object buffer pass is all you'd need here.

To invert the object buffer for the Twixtor BG channel, you'll precomp it and add the Invert effect [link].

The Twixtor Pro manual does go over these features, but I found it a bit hard to follow. You can download the Twixtor 5 example projects [link] for some examples of how to use the advanced features in Twixtor Pro in AE. Having both the manual and the example projects in front of you may make it easier to understand.

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

Nick LyonsRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 5, 2011 at 9:50:36 pm

Thanks so much. I'll give this a go and report back soon.


Return to posts index

Nick LyonsRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 5, 2011 at 11:13:49 pm

Ok, so I've rendered out the obj buffers easily. Added them to my scene and applied the first one as FG1. I inverted the second ontop of a pre-comp, but couldn't figure out how to add anything but a mask to the the BG layer, so I created a mask around the train and added that.

I also read to keep the FG on alpha, but as an alpha it made the scene look like trapcode shine was applied to it.

When I mess with the sensitivity it changes the warping around but doesnt really remove it.

Here's a picture of my file

http://i.imgur.com/Mpz0N.jpg


Return to posts index


Walter SoykaRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 4:50:04 pm

Sorry, Nick, I was working from memory and I misled you. Twixtor's BG channel does not take a matte, as I had previously suggested. You only need to provide mattes for foreground elements.

If you're getting funky edges around your matted foreground objects, you can try expanding the FG matte a little. Precomp the matte (object buffer pass). Within the precomp, expand the matte a little with Minimax, and maybe feather the edge just a touch with Fast Blur.

Looking at your screen shot, I see you're not using masks correctly. With Twixtor, masks do not limit the effect to specific areas. Rather, they are animated splines that guide the motion estimation.

You don't want to roughly outline your train with the mask; you want to look for the specific areas (usually edges) that are glopping up and add a mask that helps Twixtor track the boundaries of the feature as it moves. I usually use open masks. Animate your mask/spline over time to track the shape and path of the edge with the Source view. Twixtor will use your animated spline -- rather than its own tracking -- to determine to the motion of the pixels underneath that spline.

The goal is to follow specific features, not the object as a whole. You will often need to use multiple splines. This is why Twixtor requires you to specify a first and last mask for each BG/FG1/FG2/FG3 layer. It will use all the masks in between the first and last mask that you specify to guide motion estimation for that layer. (Please note that the term "layer" is somewhat confusing in this context: I'm not talking about AE layers, since all this is happening on the single layer with Twixtor applied. Rather, I'm talking about Twixtor's internal separation of three individual foreground layers from the background layer.)

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

Nick LyonsRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 7:12:46 pm

Thanks again Walter.

I finally figured out how to create a matte using an object buffer. I then applied the obj as FG Matte 1 as a precomped luma matte. It's working great to cut the train out of the scene, but now my problem is, how do I reveal the background? I tried adding the twixtored background but thats warped.

Here's a picture:

http://i.imgur.com/JksfY.jpg

Also, I read up on the manual. It helped me get the idea, but didn't seem to be complete after luma matting the object.

http://www.tepproject.com/manual/Twixtor/RSTwixtorUsersManual.htm#FG Stuff


Return to posts index

Dave LaRondeRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 7:36:34 pm

I presume you shot at 29.97.

Walter's advice on Twixtor is as good as you'll get, but I have to tell you: slowing down footage by a factor of seven isn't exactly a cakewalk, and your results often are iffy. You're asking Twixtor to invent six frames between one original frame and the next original frame. That's asking a lot.

As always, the best way to create slomo is to shoot at a faster frame rate. It's too bad this stuff isn't at 59.94. You could have asked Twixtor to invent only 3 frames in between the originals.

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


Return to posts index


Nick LyonsRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 7:42:59 pm

This is my first time doing slowmo for 3D, so I wanted to make it as smooth as possible. What I did was render the frames that I needed as slowmo in Cinema at 210fps and everything else was 30. So I was guessing this would remove the possibility of warping.

In AE I interpreted the footage to 210, and put the input fps for Twixtor at 30, since that's what I've seen work in the past. I suppose it's just going to take some exploring to get this to work, as I've only used twixtor one other time.

Thanks again Walter and Dave


Return to posts index

Dave LaRondeRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 7:51:03 pm

[Nick Lyons] "What I did was render the frames that I needed as slowmo in Cinema at 210fps and everything else was 30. So I was guessing this would remove the possibility of warping.

In AE I interpreted the footage to 210, and put the input fps for Twixtor at 30"


Well, then! Your AE task become, much MUCH simpler: highlight the high-frame-rate footage, go File>Interpret>Main and change the frame rate to 30. You're done!

But I have to tell you something else, too: unless this is intended for web-only video or some fancy digital video player -- no broadcast, no DVD, no Blu-Ray, -- you shouldn't work at 30 frames/sec; it should be 29.97 frames/sec.

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


Return to posts index

Walter SoykaRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 7:52:30 pm

[Nick Lyons] "What I did was render the frames that I needed as slowmo in Cinema at 210fps and everything else was 30. So I was guessing this would remove the possibility of warping... In AE I interpreted the footage to 210,"

AE maxes out at 99 fps.

If you interpret the 210fps footage at 30fps, you'll get an instant 7x slowdown, no Twixtor required.

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


Nick LyonsRe: Twixtor Warping on 210 fps 3D footage (pictures)
by on Sep 6, 2011 at 7:57:28 pm

Excellent! I didn't even think of that. Thank you both so much for all your time.


Return to posts index

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