MATRIX ENCODER WITH IMPROVED CHANNEL SEPARATION

摘要

An encoder is disclosed for use in a surround sound system wherein at least four audio input signals (FL, FR, RL, RR) representing an original sound field are encoded into two channel signals (L, and the encoded two channel signals are decoded into at least four audio output signals (FL′, FR′, RL′, RR′) corresponding to the four audio input signals. The encoder includes matrix means connected to receive the four audio input signals for encoding the four input signals into two channel (L and R) output signals. The matrix means includes means responsive to the four input signals for producing Lenc and Renc output signals as follows: Lenc=FL+kFR+jRL+jkRR Renc=FR+kFL−jRR−jkRL wherein k denotes a transformation or matrix coefficient having a value that is steered dynamically based on level of rear signal (RL+RR) content relative to front signal (FL+FR) content. An encoding method for use in a surround sound system is also disclosed.

主权项

1. An encoder for use in a surround sound system wherein at least four audio input signals (FL, FR, RL, RR) representing an original sound field are encoded into two channel signals (L, R) and said encoded two channel signals are decoded into at least four audio output signals (FL′, FR′, RL′, RR′) corresponding to said four audio input signals, said encoder including:
matrix means connected to receive said four audio input signals for encoding said four input signals into two channel (L and R) output signals, said matrix means including means responsive to said four input signals for producing Lenc and Renc output signals as follows:
Lenc=FL+kFR+jRL+jkRR Renc=FR+kFL−jRR−jkRL wherein k denotes a transformation or matrix coefficient having a value substantially 0.207 and j denotes a 90 degree phase shift.