Audio distribution system, an audio encoder, an audio decoder and methods of operation therefore

摘要

A stereo audio encoder ( 100 ) comprises a parametric stereo encoder ( 115 ) which generates a mono signal and parametric stereo parameters for at least a high frequency part of an input stereo signal. A stereo intensity encoder ( 117 ) generates stereo intensity data for the mono signal. The mono signal and intensity data are encoded in accordance with an encoding standard such as MPEG Layer II and the parametric stereo parameters are included in the ancillary data sections by an output processor ( 113 ). Thus, a legacy decoder (such as an MPEG Layer II decoder) may generate a stereo signal using the stereo intensity data whereas a higher complexity decoder may generate a high quality audio signal using the parametric stereo parameters. A stereo decoder ( 200 ) receives the encoded data from the encoder ( 100 ). An intensity decoder ( 203 ) generates a stereo signal using intensity data. This is fed to a parametric stereo decoder ( 207 ) which processes the stereo signal in accordance with extracted parametric stereo data.