Exported MP4 Alpha Channel Video Transparency not showing in FCP

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Exported MP4 Alpha Channel Video Transparency not showing in FCP

I exported an animation from Motion to mp4 with the Export Movie dialog Color channels set to "Color + alpha". The result is a file with a default black background color. I believe the alpha channel is not encoded to the mp4 since Scoop! returns the line:

Chroma subsampling : 4:2:0

Motion project properties tab says:

Background: Transparent

And I thought I did as I should, but did I forget some extra setup in Motion before exporting?

FCP 10.5.4

Motion 5.5.3

Br,

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Claude

Posted on Mar 30, 2023 1:27 AM

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Answer 1

Mar 30, 2023 1:34 AM in response to claude_210

What codec did you use? Not all codecs support Alpha Channel.

You may use ProRes 4444, or HEVC.

Also: in FCP, set your background to Checkerboard instead of black to make sure that you are seeing the transparency. Otherwise, transparent or black cannot be distinguished visually.

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