Graphics Gems III (IBM Version)

1.4

A SIMPLE COLOR REDUCTION FILTER

Dennis Bragg,     Graphics Software, Inc., Bullard, Texas

Publisher Summary

This chapter describes a simple filter that reduces a 24-bit color raster image to 15 significant bits and eliminates the problem of visible color stepping. The resulting image can be displayed directly on a 16-bit frame buffer or used as input to a color-quantization method for further reduction in the number of colors in the image. Raster images are often stored as an array of 24-bit pixels with 8 bits allocated to each red, green, or blue (RGB) component. Each RGB component holds one of 256 possible intensity levels. Frame buffers that can display 24-bit color images are not always readily available. Color displays that use 8-bit ...