Method and system for compressing digital images

Abstract

This invention relates to techniques for compressing images, particularly color images. The invention forms a lightly decodable compression technique for the color information in digital color images and video. The invention is based on an idea that an active color area in a color map is defined. The active area comprises all colors of the image under compression. Further a coordinate system is formed for the active area. The colors in the active area can be quantized using a grid, wherein each node of the grid represents a color. Since the active area is smaller than the total color map area, fewer bits are needed to index the active colors in the active area. Saving the bits increases the compression of colors when compressing the image. The color values of the image are mapped using the indices of the active color area.

Dependencies are inferred from the claim text.