This content has been marked as final. Show 6 replies
Import both image sequences into your project.
In your timeline, have your alpha image sequence above your RGB (jpeg) image sequence. Select the "Alpha Matte" track matte option on your RGB layer. Do a search on "Track Mattes" using the online help for more info.
Actually, they probably provided b&w mattes, in which case you'd select Luma Matte (or inverted Luma matte).
Derp. I think I gave that advice correctly a day or two ago.
Success! I got both in as sequences and clicked on Luma Track Mat for the bottom layer. Now I need a way to move this animation into other AE compositions. I exported a Quicktime movie with an alpha channel. BTW, I could not be sure the QT movie has an alpha channel by looking at its properties. I imported it into another composition and it always has a black background. Any advice?
You can precompose that animation, and combine it with other compositions. If the other compositions exist in other AE projects, you can always import any one AE project into another AE project. You don't want to use the "export" function under the file menu. You'll be better off using the "Render Queue" to generate your rendered footage. You can specify the filetype/codec/channels, etc... all very easily in the render queue. To quickly check the alpha info of a quicktime, import it into AE, and throw it over a colored background, or view it's alpha channel using the channel view options in the Composition window.
Okay. First, check the alpha channel box in the comp window (next to the R,G,B squares) to make sure that you're correctly seeing the alpha. If that looks good, then it's time to render.
Second, make sure the codec you're rendering to supports alphas.. Use QT: Animation, and make sure you enable RGB+ Alpha, Millions of colors+, 32bit.
The QT will still contain a black bg, but when you import it into another project, set the alpha in file interpolation...