ProRes 444 footage looks rotoscoped in Quicktime but not in AE

[Kevin Camp]

when you render with alpha from ae, the rgb areas that have a zero alpha level are rendered with the comp’s background color (often black).

in ae, and any software that can read the alpha channel, when you see that footage those areas should be transparent and you should see any layers/footage that is under them.

many players, like qt, they won’t see/use the alpha, so you would only display the rgb portion of the file, so you would see black (or the comp’s background color), and if it was straight-unmatted, you’d see the ugly edges too.

if you are seeing something different, then i’d double check that you are indeed bringing the same rendered clip back into ae and viewing it in an empty comp. if you wanted to see what it would look like without the alpha (to compare with what qt should look like), add an effect like shift channels and set the take alpha to full on.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Johnny Smith]

I know what it’s supposed to do, but for some funky reason it’s not doing it. I’m bringing in the exact same file for sure. Quicktime shows black background which tells me i’m not crazy and I in fact pre-rendered the right comp. However that file in AE looks identical to the original pre-rotobrush file. Something really strange is going on, really hoping someone on here can figure this out.

[Johnny Smith]

maybe somehow the Alpha channel is the background? Since QT can’t see it it shows black, and AE shows both background and foreground. That still doesn’t make sense though because of my smooth/feather etc settings of rotobrush. I would have seen some sort of a line between the foreground and background if that was the case. I can’t think of anything else.

[Johnny Smith]

Dave, the rendered file’s Alpha channel is solid white.
The unrendered comp’s Alpha channel is white where the image is supposed to be and black where it’s supposed to be transparent.

[Brian Charles]

[Johnny Smith] “the rendered file’s Alpha channel is solid white.”

So its not rendering the alpha. Just checking –  are the render settings RGBA or RGB?

[Johnny Smith]

Don’t see an option for RGBA vs RGB anywhere in the render settings. Once I select 444 I select RGB + Alpha. I’m in CS5.

[Todd Kopriva]

See this:
https://blogs.adobe.com/toddkopriva/2010/05/prores-4444-and-prores-422-in.html

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Todd Kopriva, Adobe Systems Incorporated
Technical Support for professional video software
After Effects Help & Support
Premiere Pro Help & Support
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[Johnny Smith]

This does sound like a solution BUT there is no MediaCoreQTCodecRulesCS5.xml file on my system.

I might have already followed those instructions a year ago when I experienced the same issue. Not sure.