Patent ID: 8842198

Claim:
An audio signal processing device comprising: a first microphone configured to pick up audio and output a first audio signal; a second microphone configured to pick up said audio and output a second audio signal; a first frequency converter configured to convert said first audio signal to a first audio spectrum signal; a second frequency converter configured to convert said second audio signal to a second audio spectrum signal; an operating sound estimating unit configured to estimate, based on the correlation between a sound emitting member that emits an operating sound and said first and second microphones, an operating sound spectrum signal indicating said operating sound, by calculating said first and second audio spectrum signals; and an operating sound reducing unit configured to reduce said estimated operating sound spectrum signal from said first and second audio spectrum signals, wherein said sound emitting member is a driving device, wherein said operating sound is a mechanical sound emitted at the time of operation of said driving device, wherein said operating sound estimating unit estimates a mechanical sound spectrum signal that indicates said mechanical sound as said operating sound spectrum signal, and wherein said operating sound estimating unit calculates said first and second audio spectrum signals so as to attenuate audio components arriving to said first and second microphones from a direction other than said driving device, thereby dynamically estimating said mechanical sound spectrum signal during operation of said driving device.