A scalable lossy to lossless audio coder for MPEG-4 lossless audio coding

In this paper, we present Advanced Audio Zip (AAZ), a scalable lossless audio coding technology that was recently selected as the reference model for MPEG audio scalable lossless coding (SLS) work. AAZ provides excellent compression performance while delivering fine grain bit-rate scalability from lossy to lossless coding. Moreover, AAZ provides backward compatibility to the MPEG advanced audio coding (AAC) system by embedding an AAC compliant bit-stream into the lossless bit-stream. As a result, AAZ serves as a universal coding solution with functionalities that were previously offered by several distinct audio coding technologies such as lossless audio coding, perceptual audio coding, or scalable audio coding; and maximizes the interchangeability for digital audio contents migrating among these application domains.