Method and apparatus for replicating a two-color original image with foreground and background colors exchanged

摘要

Replication of a two-color original image with foreground and background colors exchanged is effected on a received signal representing the color information of each successive pixel of a two-color original image by generating a histogram of the color data distribution for each color plane of the original image, determining a translation point within each histogram, and performing a histogram translation of the color plane image data about the translation point. The translation point may be determined by selecting the approximate midpoint between the foreground information and the background information in each histogram as the translation point, or by selecting the statistical average of each histogram as the translation point. Once the translation point is determined, a new color data value for each pixel in a color plane is selected by subtracting the pixel's original color data value from twice the color data value of the translation point.