Sound processing device and sound processing method

A sound processing device comprising:

• a processor that performs:
• obtaining a first sound signal collected by a first microphone and a second sound signal collected by a second microphone;
• obtaining a first frequency spectrum that corresponds to the first sound signal and a second frequency spectrum that corresponds to the second sound signal;
• calculating a level difference between a level of each of frequency components in the first frequency spectrum and a level of each of frequency components in the second frequency spectrum;
• calculating a spread of a distribution of the level difference during a prescribed period for each of the frequency components;
• determining a gain to be multiplied to the frequency component in the first frequency spectrum and a gain to be multiplied to the frequency component in the second frequency spectrum in accordance with the spread of the distribution of the level difference;
• multiplying the frequency components in each of the first and second frequency spectra by the determined gain and converting the first and second frequency spectra after the multiplication by the gain respectively into a first sound output signal of a time domain and a second sound output signal of the time domain;
• and
• storing the first and second sound output signals in a sound file storage.

A sound processing method comprising:

• obtaining, by a computer, a first sound signal collected by a first microphone and a second sound signal collected by a second microphone;
• obtaining, by the computer, a first frequency spectrum that corresponds to the first sound signal and a second frequency spectrum that corresponds to the second sound signal;
• calculating, by the computer, a level difference between a level of each of frequency components in the first frequency spectrum and a level of each of frequency components in the second frequency spectrum;
• calculating, by the computer, a spread of a distribution of the level difference during a prescribed period for each of the frequency components;
• determining, by the computer, a gain to be multiplied to the frequency component in the first frequency spectrum and a gain to be multiplied to the frequency component in the second frequency spectrum in accordance with the spread of the distribution of the level difference;
• multiplying, by the computer, the frequency components in each of the first and second frequency spectra by the determined gain and converting the first and second frequency spectra after the multiplication by the gain respectively into a first sound output signal of a time domain and a second sound output signal of the time domain;
• and
• storing, by the computer, the first and second sound output signals in a sound file storage.