“Rounding” colour values to the nearest of a small set of colours

Question

Preamble

As a part of a project I\'m working on I am trying to provide a convenient way to search for images in our system. We currently provide se

Answer 1

Depending on the number of colors you're looking for, why not try using bitwise operators (PHP's reference here, since you mentioned it in the question) to reduce the number of significant digits? You could round the RGB values before shifting to increase accuracy as well.