animating a matte

[Cory Petkovsek]

After Effects can use just about anything as a matte, as long as it is prepared properly. Since your fish shape is a photoshop file, you’ve got to animate it somehow before you can use it as an animated matte.

It would probably be easier if it was a vector in illustrator, rather than raster in photoshop. Either way, bring it in to your compositor and animate it. Use that animation as a matte.

How you animate it depends on your program. You can create every frame. Or you can use a program that will allow you to set keys and it will interpolate the tweens based upon temporal and spatial curves you can set. AE is one such program.

Cory

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Cory Petkovsek
Corporate Video

[Mark Suszko]

Are you doing this effect on the timeline of your NLE, or in a compositing program like Aftereffects or Apple Motion?

If you’re doing it in the timeline, You could keyframe the parts that need to move, all together, by keyframing one element, then copy-pasting that set of keyframes into the tracks for the other elements in your “stack. There may be canned effects like a water ripple or flag/wind ripple you can apply on the timeline to the specific tracks, to get the swimming action. And nobody says you have to make it all happen in one pass: you could render out part of this, then bring that back in and have fewer elements to deal with in the timeline.

But I’d rather try to do this effect in a compositor like Motion or AE, which is set up to amke these jobs easy. Plug-in effects for swimming type action are already there, built and ready to apply and modify to suit.

[Walter Soyka]

[Cory Petkovsek] “After Effects can use just about anything as a matte, as long as it is prepared properly. Since your fish shape is a photoshop file, you’ve got to animate it somehow before you can use it as an animated matte… How you animate it depends on your program. You can create every frame. Or you can use a program that will allow you to set keys and it will interpolate the tweens based upon temporal and spatial curves you can set. AE is one such program.”

I’d try a displacement effect on the matte first, to see if I could get close enough to a swimming motion without keyframing everything by hand. If that didn’t work, I’d move to some kind of warp effect and animate.

Jennifer, this forum (Broadcast Design / Motion Graphics) is pretty general. If you were asking about how to do this specifically in Apple Motion, try the COW’s Apple Motion forum [link].

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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