Converting multi-microphone captured signals to shifted signals useful for binaural signal processing and use thereof

A method comprising:

• capturing first, second and third audio signals from respective first, second and third microphones of at least three microphones spaced apart at predetermined distances and arranged in a predetermined geometric configuration;
• forming a first resultant signal based on the first and second audio signals;
• forming a second resultant signal based on the first and second audio signals;
• determining, using at least said first and second audio signals in view of the predetermined geometric configuration, a potential direction of a sound source relative to the at least three microphones;
• determining an angle of arriving sound relative to the first and second microphones, the angle having two possible values;
• using a best correlation, selecting one of the two possible values of the angle as a direction of the sound source relative to the at least three microphones using the third microphone;
• determining left and right output channel signals using the first and second resultant signals and information corresponding to the direction;
• and
• outputting the left and right output channel signals.

An apparatus, comprising:

• one or more processors, and
• one or more non-transitory memories including computer program code, the one or more non-transitory memories and the computer program code configured, with the one or more processors, to cause the apparatus to perform at least the following:
• estimate directional information based on multiple input channel signals representing at least one arriving sound from a sound source captured with respective multiple microphones that have respective known locations relative to each other, wherein the multiple input channel signals include at least a first input channel signal and a second input channel signal and estimating comprises finding a time delay so as to remove a time difference between said first input channel signal and second input channel signal;
• derive a mid-signal and a side signal on a basis of said first input channel signal, said second input channel signal and said estimated directional information, wherein deriving further includes deriving the mid-signal as a mid-signal combination based on at least the first input channel signal and the second input channel signal, and deriving the side signal as a side signal combination based on at least the first input channel signal and the second input channel signal, wherein at least one of the mid-signal combination and the side signal combination minimizes a distortion of the at least one arriving sound caused with the at least one arriving sound arriving at different times to at least two or more of the multiple microphones;
• and
• generate an output signal comprising a plurality of output channels using said mid-signal, said side signal and said estimated directional information such that the output signal retains a spatial representation of the at least one arriving sound.

A computer program product embodied in a non-transitory computer memory and comprising instructions the execution of which with a processor results in performing operations that comprise:

• estimating directional information based on multiple input channel signals representing at least one arriving sound from a sound source captured with respective multiple microphones that have respective known locations relative to each other, wherein the multiple input channel signals include at least a first input channel signal and a second input channel signal and said estimating comprises finding a time delay so as to remove a time difference between said first input channel signal and second input channel signal;
• deriving a mid-signal and a side signal on a basis of said first input channel signal, said second input channel signal and said estimated directional information, wherein said deriving further includes deriving the mid-signal as a mid-signal combination based on at least the first input channel signal and the second input channel signal, and deriving the side signal as a side signal combination based on at least the first input channel signal and the second input channel signal, wherein at least one of the mid-signal combination and the side signal combination minimizes a distortion of the at least one arriving sound caused with the at least one arriving sound arriving at different times to at least two or more of the multiple microphones;
• and
• generating an output signal comprising a plurality of output channels using said mid-signal, said side signal and said estimated directional information such that the output signal retains a spatial representation of the at least one arriving sound.

A method comprising:

• receiving a first audio signal from a first microphone, a second audio signal from a second microphone, and a third audio signal from a third microphone, where locations of each of the first microphone, the second microphone, and the third microphone are known, and where each of the first audio signal, the second audio signal, and the third audio signal comprises sound arriving from a sound source;
• determining a first potential direction of the sound arriving from the sound source based on analysis of the first audio signal and the second audio signal;
• determining a second potential direction of the sound arriving from the sound source based on analysis of the first audio signal and the second audio signal;
• determining a combined audio signal, where the combined audio signal comprises the first audio signal and a shifted version of the second audio signal;
• determining one of the first potential direction or the second potential direction as a direction of the sound arriving from the sound source based on the third audio signal;
• and
• generating one or more output signals based, at least partially, on the direction of the sound arriving from the sound source and the combined audio signal.