Binaural cue coding: a novel and efficient representation of spatial audio

We present a novel concept for representing multi-channel audio signals: Binaural Cue Coding (BCC). BCC aims at separating the basic audio content and the information relevant for spatial perception. A multi-channel audio signal is represented as a mono signal and BCC parameters. We present two types of applications of BCC. Firstly, a number of separate sound source signals are reduced to a mono signal and BCC parameters. In this case, the decoder has control over the location of each source in auditory space. In other words, the decoder can render spatial images as if the separate source signals were given. Secondly, a multi-channel audio signal is reduced to a mono signal and BCC parameters. In this case the decoder generates a multi-channel signal with a spatial image similar to the spatial image of the input signal of the encoder. Results from a subjective test suggest that BCC, combined with existing mono audio coders, offers better quality than conventional stereo and multi-channel perceptual transform audio coders for a wide range of bitrates.