PROBLEM TO BE SOLVED: To provide a mechanism driving sound reduction apparatus for reducing a mechanism driving sound by suppressing the generation of speech distortion and an increase in mechanism driving sound of a motor etc., when sound recording level of video recording equipment etc. abruptly varies.;SOLUTION: Two kinds of time domain signals of time domain frame data (S8) obtained by performing spectrum subtraction (S7) by a subtract coefficient corresponding to a sound recording level before abrupt sound recording level variation and inverse Fourier transformation, and time domain frame data (S10) obtained by performing spectrum subtraction (S9) by a subtract coefficient corresponding to a sound recording level after the variation are generated in the frame where the abrupt sound recording level variation occurs in order to reduce a noise sound due to the mechanism driving sound during sound recording, and the two time domain signals are mixed (S12) at a mixing ratio corresponding to the timing in the frame where the abrupt sound recording level variation occurs to reduce the noise sound.;COPYRIGHT: (C)2008,JPO&INPIT
展开▼
