
Chapter | 3 Speech Processing
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due to the inherent (intrinsic) variability of speech, such as speaker
specificities. In this case, acoustic model adaptation techniques are
crucial. They are based on training algorithms allowing to tune the
model parameters to specific acoustic conditions, or voices, using
a reasonably small amount of adaptation samples. Maximum likeli-
hood linear regression (MLLR) [5] is a good example, which has been
applied to both speaker variability and noise. The idea is to estimate
an affine transformation of the acoustic model parameters, by max-
imising the likelihood of adaptation data from a particular speaker, to
shift the parameters ...