The invention provides a reversible eight-element discrete cosine transform system which can be realized with a practical circuit and provide transform values proximate to those obtained by actual eight-element discrete cosine transform. In 4.times.4 matrix transform which appears when eight-element...http://www.google.ca/patents/US6175661?utm_source=gb-gplus-sharePatent US6175661 - Lossless transform coding system for digital signals
