Principles and Analysis of the Squeezing Approach to Low Bit Rate Spatial Audio Coding

This paper presents a novel solution to multichannel spatial audio coding: spatial squeezing surround audio coding (S³AC). The S³AC scheme analyses a multichannel audio signal and downmixes it into a stereo signal pair containing both the monophonic properties of audio sources and their localization information; this avoids the need for side information. The approach uses time-frequency analysis of a spatial audio scene and exploits virtual sources and amplitude panning techniques to ´squeeze´ 360deg of a horizontal soundfield to a 60deg stereo signal pair. In comparison with other spatial audio coding techniques, S³AC significantly advances in-band encoding of the localization information in the original sound scene and achieves accurate recoverability of dynamic localized sources.