Why we get negative wavelet coefficient?

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Alfredo Calvo

Why not? I mean, what do you think that is the problem with negative coefficients?

Piyush Joshi

if coefficient value is zero then we know that input signal does not coincide with mother wavelet. if we get some positive coefficient value then input signal somewhat coincide with mother wavelet.

But when we get negative coefficients.

Victoriya V Abramova

Simirlarly to DCT wavelet coefficients may be positive or negative with almost equal probabilities. So, there is no specific physical value in negative coefficients. The fact that coefficient may be positive or negative is due to peculiarities of the used transform.