Accessing Adobe Stock Alpha Channel

[sarah.m]

Adobe Stock Asset: 362845689

Asset says alpha channel included. How do I access the alpha channel within after effects? Just need to ditch that background and keying is not working cleanly at all.

[Rick Gerard · Accepted solution]

I downloaded a preview copy of that footage and the first part was in color, then the second part was black and white. The black and white copy would be used as a track matte. If the format (H.264) does not support alpha channels then stock footage providers ofter provide a duplicate copy of the footage in black and white. You can do the same when you render out of the AME or the Output Module/Render Cue, just pick Alpha Only. For production masters, I always pick a mezzanine format that supports alpha channels and is 10 bit or better, but if you are tight on drive space and don't mind MPEG compression artifacts, rendering an Alpha Only copy of the footage for use as a track matte is a good alternative.

When you get the track matte setup you should also pre-compose the pair, then add Matte Choker or Light Wrap to clean up the edges. A straight luma key from the black and white copy of the footage may be a little too harsh.

[sarah.m]

Thank you so much! This worked great and finally got me back on the road for this project. Appreciate your help!