Indexed Color History in Image Coding

Abstract

System comprising: a memory that stores: an indexed color history with an entry that stores a color value of a previously encoded pixel; an encoding logic that communicates with the memory and is configured to: encode a current pixel as an index value that references the entry in the indexed color history if a color value of the current pixel is within a difference threshold based on the color value of the previously encoded pixel; otherwise, encode the current pixel as an uncompressed color or pixel value or by inserting it into the indexed color history.