The FXScript Reference

For Final Cut Pro created by Joe Maller

Blit

FXScript Reference : FXScript Functions : Blit

Blit(sourceImage, sourcePoly, destImage, destPoly, opacity)

Additional Notes

Slower than Matte
by Joe Maller on 12 Nov, 2003 22:43, Applies to: FCP 4.0.2 from:

When used to transfer one frame to another without scaling, Blit is basically the same as Matte, except nearly five times slower.

When scaling, Blit is slower than creating the same effect with a combination of BlitRect and Matte.

Basic test was 7500 iterations of a transparent image onto another image.
Scaled tests placed the transparent image scaled to 50%.

Matte: 0:51
Blit: 4:47
BlitRect & Matte: 1:20
Scaled Blit: 2:14
Based on those numbers I suspect the slowest part of the Blit function is the opacity composting. Smaller output was faster, by a value close to the scaling percentage.

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