Greedy tree growing for color image quantization

Displaying a true color image in a low cost color monitor or printer is very important in many applications. The basic problem is how to display 2²⁴ colors with K(usually K=256 or less) colors, called a color palette. The authors propose an algorithm to design the K-color palette by an unbalanced greedy binary tree. The algorithm splits the node with largest error reduction into two children by a hyperplane perpendicular to one of r,g,b axis among available nodes in the tree. The color image is then quantized by the K-color palette