The Chroma Key operator removes points by colour, the same way a green screen is keyed in video. Each point's colour is converted to HSV and points falling inside the key are discarded. It can be used to strip a backdrop or coloured props from a scene, or with **Invert** enabled to isolate them.

*[HSV]: Hue, Saturation, Value

- **Target Hue**: the centre of the key on the colour wheel, in degrees. The default of 140° targets green.

- **Hue Width**: the span of hues around the target that are keyed, in degrees.

- **Minimum Saturation**: points less saturated than this are never keyed, which protects greys and skin tones.

- **Minimum Value**: points darker than this are never keyed, which protects shadows.

- **Invert**: keep only the points inside the key and remove everything else.

- **Backend**: run the operator on the CPU or with CUDA.

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[View operator source](https://github.com/matth-av/pointcaster/blob/qt/src/plugins/operators/chroma_key/chroma_key_operator.cc)

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