1. An apparatus comprising: interface circuitry configured to receive image frames of an object, the image frames associated with a three-dimensional scan of the object; and a processor configured to: scan a first image frame of a sequence of the image frames; determine a grayscale threshold based on characteristics of the first image frame; identify gray pixel candidates in the first image frame based on the grayscale threshold; and adjust a pixel value of each pixel in the first image frame based on a chromatic adaptation transform estimation, the chromatic adaptation transform estimation based on the gray pixel candidates.