Patent ID: 8249270

Claim:
A sound signal correcting method, comprising: comparing the sound signal based on acquired sound with a noise model relating to a noise pattern; and smoothing a waveform of the sound signal, to smooth a change in a spectrum of the sound signal in a time axis direction, on the basis of the comparison result and a following formula (B): | IN ( f )′| t=α|IN ( f )′| t− 1+(1−α)| IN ( f )| t formula (B) where |IN(f)′|t is a spectrum at frequency f at time t after smoothing, |IN(f)|t is a spectrum at frequency f at time t before smoothing, |IN(f)′|t−1 is a spectrum at frequency f at time t−1 which is before time t by a predetermined time, after smoothing, and α is a correction coefficient where 0≦α≦1.