Sound image localization device, sound image localization method, and program

A sound image localizing device comprising:

• an objective function setting unit, including one or more processors, configured to set an objective function from a desired directional characteristic;
• a constraint setting unit, including one or more processors, configured to set a linear or non-linear constraint;
• an optimization unit, including one or more processors, configured to compute an optimum filter coefficient from the objective function set by the objective function setting unit and the constraint set by the constraint setting unit;
• and
• a convolution operation unit, including one or more processors, configured to compute an output acoustic signal by performing convolution of an input acoustic signal and a directivity control filter that is computed by the optimization unit, wherein filters that respectively correspond to speakers constituting a speaker array are computed by the objective function setting unit, the constraint setting unit, and the optimization unit, an acoustic beam is generated using directivity control by the speaker array, and the acoustic beam is caused to be reflected from a wall surface or a ceiling to generate a virtual sound source.

A sound image localizing method comprising:

• a directivity control filter designing step of computing a directivity control filter from a desired directional characteristic;
• a filter coefficient correction step of correcting the directivity control filter computed in the directivity control filter designing step;
• and
• a convolution operation step of computing an output acoustic signal by performing convolution of an input acoustic signal and the directivity control filter corrected in the filter coefficient correction step, wherein filters that respectively correspond to speakers constituting a speaker array are computed in the directivity control filter designing step and the filter coefficient correction step, an acoustic beam is generated using directivity control by the speaker array, and the acoustic beam is caused to be reflected from a wall surface or a ceiling to generate a virtual sound source.

A sound image localizing method comprising:

• an objective function setting step of setting an objective function from a desired directional characteristic;
• a constraint setting step of setting a linear or non-linear constraint;
• an optimization step of computing an optimum filter coefficient from the objective function set in the objective function setting step and the constraint set in the constraint setting step;
• and
• a convolution operation step of computing an output acoustic signal by performing convolution of an input acoustic signal and a directivity control filter that is computed in the optimization step, wherein filters that respectively correspond to speakers constituting a speaker array are computed in the objective function setting step, the constraint setting step, and the optimization step, an acoustic beam is generated using directivity control by the speaker array, and the acoustic beam is caused to be reflected from a wall surface or a ceiling to generate a virtual sound source.