Two-to-five channel sound processing

While stereo music reproduction was a dramatic advance over mono, recently a transition to multichannel audio has created a more involving experience for listeners. An algorithm to convert stereo to five-channel sound reproduction is presented. An effective sound distribution to the surround channels is achieved by using a cross-correlation technique, and a robust stereo image is obtained using principal component analysis. Informal listening tests comparing this scheme with other methods revealed that the proposed algorithm is preferred for both on and off the reference listening position (sweet spot).