Lossless Audio Coding with Bandwidth Extension Layers

Layered audio coding typically offers reduced distortion as bit rate is increased, but that distortion is spread across the entire band until the lossless coding bit rate is reached and distortion is eliminated. We propose a layered audio coding paradigm of bandwidth extension, rather than distortion reduction. For example, a core layer can provide lossless coding of a 24 kHz bandwidth signal (fs=48 kHz), then first and second bandwidth extension lossless layers can extend that signal to losslessly coded 48 and then 96 kHz bandwidths (fs=96 and 192 kHz).