Virtual microphones for multichannel audio applications

Multichannel audio can immerse a group of listeners in a seamless aural environment. Consumer media such as DVD and DVD-Audio allow the delivery of multiple (up to 10) channels of audio today. However, although there are thousands of music recordings available in two-channel stereo, only a handful have been recorded with multiple channels. We present a novel method for synthesizing multiple microphone signals from a smaller set of signals recorded in a particular venue. These synthesized “virtual” microphone signals can be used to produce multichannel recordings that accurately capture the acoustics of a particular venue. Our method uses linear prediction to generate a set of IIR filters that can be used to synthesize microphone signals at various locations within the hall, while preserving the correct acoustical characteristics of the venue. Applications of this method include transmission of multichannel audio over low bandwidth networks, as well as remastering of existing monophonic and stereophonic recordings for multichannel rendering