A method and apparatus for speaker recognition is provided that matches the noise
in training data to noise in testing data using spectral addition. Under spectral
addition, the mean and variance for a plurality of frequency components are adjusted
in the training data and the test data so that each mean and variance is matched
in a resulting matched training signal and matched test signal. The adjustments
made to the training data and test data add to the mean and variance of the training
data and test data instead of subtracting from the mean and variance.