Acoustic signal processing apparatus, acoustic signal processing method and program

An acoustic signal processing method comprising:

• a transaural processing step that generates a first binaural signal for an input signal, which is an acoustic signal for a virtual sound source deviated to left or right from a median plane of a predetermined listening position, by using a first head-related transfer function between an ear of a listener at the listening position farther from the virtual sound source and the virtual sound source, generates a second binaural signal for the input signal by using a second head-related transfer function between an ear of the listener closer to the virtual sound source and the virtual sound source, and generates a first acoustic signal and a second acoustic signal by performing crosstalk correction processing on the first binaural signal and the second binaural signal as well as attenuates a component of a first frequency band and a component of a second frequency band in the input signal or the second binaural signal to attenuate the component of the first frequency band and the component of the second frequency band of the first acoustic signal and the second acoustic signal, the first frequency band being lowest and the second frequency band being second lowest at a predetermined frequency or more of frequency bands in which notches, which are negative peaks with amplitude of a predetermined depth or deeper, appear in the first head-related transfer function;
• and
• an auxiliary signal synthesizing step that generates a third acoustic signal by adding an auxiliary signal to the first acoustic signal, the auxiliary signal including a component of a predetermined third frequency band of the input signal, in which the component of the first frequency band and the component of the second frequency band are attenuated, or the component of the third frequency band of the second binaural signal, in which the component of the first frequency band and the component of the second frequency band are attenuated.

A program for causing a computer to execute processing including:

• a transaural processing step that generates a first binaural signal for an input signal, which is an acoustic signal for a virtual sound source deviated to left or right from a median plane of a predetermined listening position, by using a first head-related transfer function between an ear of a listener at the listening position farther from the virtual sound source and the virtual sound source, generates a second binaural signal for the input signal by using a second head-related transfer function between an ear of the listener closer to the virtual sound source and the virtual sound source, and generates a first acoustic signal and a second acoustic signal by performing crosstalk correction processing on the first binaural signal and the second binaural signal as well as attenuates a component of a first frequency band and a component of a second frequency band in the input signal or the second binaural signal to attenuate the component of the first frequency band and the component of the second frequency band of the first acoustic signal and the second acoustic signal, the first frequency band being lowest and the second frequency band being second lowest at a predetermined frequency or more of frequency bands in which notches, which are negative peaks with amplitude of a predetermined depth or deeper, appear in the first head-related transfer function;
• and
• an auxiliary signal synthesizing step that generates a third acoustic signal by adding an auxiliary signal to the first acoustic signal, the auxiliary signal including a component of a predetermined third frequency band of the input signal, in which the component of the first frequency band and the component of the second frequency band are attenuated, or the component of the third frequency band of the second binaural signal, in which the component of the first frequency band and the component of the second frequency band are attenuated.