Exporting video with an alpha channel

[EdwardMartinIII]

I have a number of effects that I've purchased that are quicktimes, with alpha channels already built into the video. Explosions, muzzle flashes, and so forth.

This is very handy.

How do I produce similar video clips, with embedded alpha channels? Let's say I've got this really fantastic sequence and I want to export it with an alpha channel. How do I do that?

I'm using AE CS3 all updated.

Edward

"Cut a hole in the door. Hang a flap. Criminy, why didn't I think of this earlier?!" -- inventor of the cat door

 

[maruyama]

Just export using a codec that supports an alpha channel or MILLIONS+.

This is a great way to create a library of effects that are already prerenedered

Ko Maruyama
Free Tutorials

http://homepage.mac.com/komaruyama/Tutorials

 

[EdwardMartinIII]

Ah, is there a way to tell which codecs will do it and which won't? I'm trying to avoid trying them all. 8)

Edward

"Cut a hole in the door. Hang a flap. Criminy, why didn't I think of this earlier?!" -- inventor of the cat door

 

[maruyama]

Lossless will, as will most of the 10bit and 8bit versions.

Ones that DEFINITELY WON'T are JPEG, H264, SORENSON, the highly compressed codecs.

ANIMATION is by far my favorite codec when embedding an alpha channel. It keeps the alpha clean.

Ko Maruyama
Free Tutorials

http://homepage.mac.com/komaruyama/Tutorials