Patent ID: 8488806

Claim:
A signal processing apparatus for reconstructing an original signal outputted from a target one of a plurality of wave sources as a target signal, comprising: (a) a plurality of observation units for observing a plurality of original signals outputted from said plurality of wave sources as a mixed signal of the plurality of original signals; (b) a separation signal generation unit for generating a plurality of separation signals which are independent from one another from said mixed signals for one frame, the plurality of separation signals being observed by each of said observation units and being converted into separation signals in a frequency region, for each of frequency bins in said frame; (c) a mask processing unit for judging a noise condition of a first separation signal corresponding to said target signal out of said plurality of separation signals on the basis of said first separation signal and second separation signals, said second separation signals are said plurality of separation signals other than said first separation signal, generating a noise removal signal by removing a first noise component obtained on the basis of a judgment result on said noise condition from said first separation signal and generating a noise condition signal on the basis of said judgment result on said noise condition, for each frequency bin in said frame; (d) a noise amount measuring unit for measuring the amount of noise included in said first separation signal for each said frame on the basis of said noise condition signal for each said frequency bin, said noise condition signal is inputted from said mask processing unit; (e) a noise signal selection unit for selecting one of said second separation signals as a noise signal for each said frequency bin on the basis of said amount of noise measured by said noise amount measuring unit; and (f) a noise removing unit for removing a second noise component generated on the basis of said noise signal from said noise removal signal, for each said frequency bin, and outputting said noise removal signal obtained by removing said second noise component as said target signal.