Chroma Keying & Alpha Channels

wazungu wrote on 8/13/2002, 11:09 AM

Just lurking in the forums today, looking for information about chroma keying and video alpha channels. It looks like VV has a chroma key [track] that will let good blue/green screen footy be composited over other tracks. Question: how does that compare with, say, Ultimatte?

I'm considering using the Ultimatte Plug-in with AfterEffects; I could render out a movie with an alpha channel ("travelling matte"). Could this movie with an extra alpha channel be then imported into VV? It sounds like VV can export an AVI with one, does it go both ways?

Any thoughts/experiences would be most welcome. Thanks!

Comments

Tyler.Durden wrote on 8/13/2002, 8:41 PM

Any keying with dv is a compromise, and Vegas does it fairly well. Ultimatte is very good, but keying is their specialty.

Vegas can use an uncompressed AVI with alpha, uncompressed Quicktime with alpha too. You can also use a matte generated by AE to use as a moving matte (hi-con) with one click.

HTH, MPH

SonyEPM wrote on 8/14/2002, 8:35 AM

Yes, the alpha goes both ways (import or export) with uncompressed .avi. For moving back and forth between AE, uncompressed .avi is the best (highest quality, most flexible) option.