The field of lossless image compression studies the various ways to represent image data in the most compact and efficient manner possible that also allows the image to be reproduced without any loss. There are many ways that this is accomplished and the most efficient strategy is to leverage the fundamental concepts of entropy reduction through decorrelation. The application of decorrelation methodologies prior to entropy coding is a modeling-coding strategy that produces significant results. This study focuses on the usage of the exclusive-or logic operator as a decorrelation filter. The exclusive-or logic operator is simply and reversibly applied to continuous-tone images for the purpose of extracting differences between neighboring pixels. The results of the exclusive-or operator based decorrelation filter are then processed through entropy encoding using Huffman coding. Experiments indicate that the exclusive-or operator based decorrelation filter has a significant impact on reducing entropy and therefore compression results.
['Takiyah K. Cooper', 'Ahmed H. Desoky']
Huffman coding analysis of XOR filtered images