Patent ID: 7596494

Claim:
A method of identifying a clean speech signal from a noisy speech signal, the method comprising: a processor identifying a set of log-magnitude frequency values for each of a plurality of frames that represent the noisy speech signal; the processor filtering the log-magnitude frequency values of the noisy speech signal to smooth the log-magnitude frequency values over time to form filtered noisy values by applying the log magnitude frequency values of the noisy speech signal to a Finite Impulse Responsive Filter having a set of filter parameters wherein at least one of the filter parameters of the set of filter parameters differs from another of the filter parameters of the set of filter parameters; the processor determining parameters of at least one posterior probability distribution of at least one component of a clean signal value based on the set of filtered noisy values without applying a frequency-based transform to the set of filtered noisy values, the posterior probability distribution providing the probability of a log-magnitude frequency value for a clean speech signal given a filtered noisy value; the processor using the parameters of the posterior probability distribution to estimate a set of log-magnitude frequency values for a clean speech signal; and the processor using the log-magnitude values for the clean speech signal to produce an output clean speech signal.