aa_HueKey v1.0

Colour keyer written in Blink, with options to key “Hue”, or “Chroma + Luma”. Needs an alpha channel to work. The color difference key is based on other tools such as DespillMadness from Andreas Frickinger, LumaPictures’ L_Despill and Adrian Pueyo´s apDespill. The main hue rotation matrix is based on Mark Ransom´s code.

It has two modes that will give different results:

“Hue Only” will just key based on hue, not taking into account color saturation or luminance. It includes a multiplier to fine tune the mask.

“Chroma + Luma” will key based on the chrominance of the image and has an extra control to adjust how much the luminance should affect the mask.

The Chroma´s “Upper Threshold” and “Lower Threshold” should ideally not be tweaked too much as they give harsher results than the Luma knob.

The “Luma Accuracy ” knob will help if the Chroma key is not enough to isolate colours. By default is set to 0.2 (range from 0 to 1).

The “Overall Post Process” should be tweaked last, as it is just a colour correction applied after the main calculation has been done.

Comments and suggestions are welcome!

Asier Aparicio, 2018

asieraparicio.net