Echo suppressing device, echo suppressing method, and echo suppressing program

An echo suppressing method for suppressing an echo caused when a reception signal is transmitted through a receiving signal path through which a signal is transmitted to a speaker and voice output from the speaker by the reception signal is input to a microphone, the echo suppressing method comprising:

• a step of acquiring an estimated echo function calculated based on a second learning reception signal in which a learning reception signal transmitted through the receiving signal path is converted into a frequency domain and a second learning signal in which a learning signal transmitted through a transmitting signal path for transmitting a signal input from the microphone when sound output from the speaker by the learning reception signal input to the microphone is converted into a frequency domain, the estimated echo stored in a storage unit, the estimated echo function having variables of a logarithm of a magnitude at each frequency of the reception signal, a frequency of the reception signal, a logarithm of a total reception value that is a summation of magnitudes of the reception signal or transmission of the reception signal in any frequency range, and a logarithm of an envelope of the total reception value;
• and
• a step of performing an echo suppressing process by inputting a value of a second reception signal in which the reception signal is converted into a frequency domain to a function representing the estimated echo to generate an echo suppressing mask, and multiplying an echo suppressing gain calculated based on the echo suppressing mask by a second transmission signal in which a transmission signal transmitted through the transmitting signal path converted into a frequency domain.

A non-transitory computer readable medium storing an echo suppressing program that causes a computer to perform

• a step of acquiring an estimated echo function calculated based on a second learning reception signal in which a learning reception signal transmitted through the receiving signal path is converted into a frequency domain and a second learning signal in which a learning signal transmitted through a transmitting signal path for transmitting a signal input from the microphone when sound output from the speaker by the learning reception signal input to the microphone is converted into a frequency domain, the estimated echo stored in a storage unit, the estimated echo function having variables of a logarithm of a magnitude at each frequency of the reception signal, a frequency of the reception signal, a logarithm of a total reception value that is a summation of magnitudes of the reception signal or transmission of the reception signal in any frequency range, and a logarithm of an envelope of the total reception value;
• and
• a step of performing an echo suppressing process by inputting a value of a second reception signal in which the reception signal is converted into a frequency domain to a function representing the estimated echo to generate an echo suppressing mask, and multiplying an echo suppressing gain calculated based on the echo suppressing mask by a second transmission signal in which a transmission signal transmitted through the transmitting signal path converted into a frequency domain.