Method and system for generating a matrix-encoded two-channel audio signal

摘要

In some embodiments, a method for generating a matrix-encoded two-channel audio signal in response to a horizontal B-format signal by performing a mixing operation. In other embodiments, a method for generating a matrix-encoded two-channel audio signal, including steps of generating microphone output signals (by capturing sound with a microphone array), and performing a mixing operation on the microphone output signals, where the mixing operation is equivalent to generating a horizontal B-format signal in response to the microphone output signals, and generating the matrix-encoded two-channel audio signal in response to the horizontal B-format signal. The microphone array is typically a small array of cardiod microphones (e.g., an array consisting of three cardiod microphones). Other aspects include systems (e.g., encoders) programmed or otherwise configured to perform any embodiment of the method for generating a matrix-encoded two-channel audio signal.

主权项

1. A method for generating a matrix-encoded two-channel audio signal, Lt, Rt, in response to a horizontal B-format signal comprising signals W =SourceSig, X=cos θ×SourceSig, and Y=sin θ×SourceSig, where SourceSig is the waveform of a source audio signal and θ is the azimuth of the source audio signal, said method including a step of:
(a) performing on the horizontal B-format signal a mixing operation having form[LtRt]=S×[WXY],where S=ejΨ×T, Ψ is a real phase shift, where T is a 2×3 matrix and wherein the matrix T is selected from the group consisting of M and Mc= M, whereM=[1+j2⁢21-j2⁢21+j2⁢21-j2⁢21+j2⁢2-1+j2⁢2]⁢⁢andMc=M_=[1-j2⁢21+j2⁢21-j2⁢21+j2⁢21-j2⁢2-1-j2⁢2].