A method and apparatus for assessing the visibility of differences between two input signal sequences, e.g., image sequences is disclosed. The apparatus comprises a perceptual metric generator having an input signal processing section, a luminance processing section, a chrominance processing section...http://www.google.se/patents/US6137904?utm_source=gb-gplus-sharePatent US6137904 - Method and apparatus for assessing the visibility of differences between two signal sequences
