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trigger an effect
Hope i’m not double posting. Apologies if i am…
My question is.
How would you trigger an effect (expression) using the luminance change of a footage clip? For example, if i had footage of waves breaking, how would i use the change to white of the waves to trigger an effect??
thanks in advance.the chairman
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2 Replies
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You should be able to use sampleImage() to detect the color change. If you’re triggering a time-based effect, your expression will need to go back through time, frame-by-frame until you find the most recent frame where the color transitioned to the target color. That will tell you how far into the effect you should be at the current frame. Also, the smaller you can make the sample size, the faster it will render.
Dan
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thank you for your time and thought Dan.
the chairman
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