Glossary
Alpha channel
A fourth channel stored beside red, green and blue that records how opaque each pixel is. It is what lets a graphic sit over other footage without a black box around it.
In Premation
The checkerboard in the viewport is transparency. WebM VP9, MOV ProRes 4444, PNG and EXR sequences carry alpha on export; MP4, GIF and the HDR formats do not, and the Export panel says which before you queue.
Related terms
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