Hierarchical multi-channel audio coding based on time-domain linear prediction

A novel hierarchical multi-channel coding scheme is proposed which exhibits a significant decrease in decoding complexity compared to earlier proposals. The new coding scheme is based on a single channel down mixing process followed by predictions of the multichannel input signals. Symmetries in the prediction filter coefficients and the prediction errors allow for a reduced number of channels which need to be transmitted. A detailed evaluation of the achievable prediction gain and the impact of quantization on the perceived quality leads to insights into the appropriate choice of system parameters. Besides the attractive feature of being usable as a hierarchic extension to existing single channel communication systems and its very low additional algorithmic delay, the transmission quality of the proposed design also scales very well with the available data rate.