A green-screen/chroma key effect utilizing Pixel Bender. With this version, the live video is compared against a reference image rather than a static color. Additionally, the alpha of the output is graduated based on the color difference between the base image and the incoming video (rather than just being either ‘on’ or ‘off’). Both of these differences may or may not be good for practical use, but can create interesting imagery.
Use the sliders to adjust the cutoff/falloff curve for the alpha. Click “Reset base image” to set the base image with which to compare any further changes in the video against. You can also choose your own background image (click “Browse…” at the bottom). Works best against a plain background and presumably best of all with proper lighting against a green background…
When I wrote the image processing routine in pure Actionscript, it ran like a slideshow. The Pixel Bender version on a multi-core system runs about 30x faster.
Pixel Bender kernel: GreenScreenEffect.pbk
Licensed under a Creative Commons Attribution 3.0 License.