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Speech Speech Enhancement Enhancement

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This is called the time domain Wiener filter

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We are looking for a frequency-domain Wiener filter, called the non-causal Wiener filter such that:

According to the projection theorem, for the error

to be minimum, the difference

has to be orthogonal to the noisy input

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Spectral SubtractionSpectral Subtraction

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We try to optimize the function:

g(.) is a function on Rk and

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The computation of Eqn1 is generally difficult. For some specific functions, Eqn1 has been derived.For instance, when g(.) is defined to be:

Where is the kth coefficient of the DFT of yt ,Eqn1 is equivalent to the popular Wiener filter

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Recursive Formula For G:

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Automatic Noise Type Selection

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