Continuous wavelet transform: Difference between revisions

Content deleted Content added
No edit summary
m General overview: There are examples of L¹&&L² functions that do not decay at infinity; taking such an example and making the substitution ω->1/ω now clearly gives a counterexample to "an admissible wavelet must have its Fourier transform, evaulated at 0, exactly zero".
Tags: Mobile edit Mobile app edit Android app edit
Line 25:
Traditionally, this constant is called wavelet admissible constant. A wavelet whose admissible constant satisfies
:<math>0<C_\psi <\infty</math>
is called an admissible wavelet. An admissible wavelet implies that <math>\hat{\psi}(0) = 0</math>, so that an admissible wavelet must integrate to zero. To recover the original signal <math>x(t)</math>, the second inverse continuous wavelet transform can be exploited.
:<math>x(t)=\frac{1}{2\pi\overline\hat{\psi}(1)}\int_{0}^{\infty}\int_{-\infty}^{\infty} \frac{1}{a^2}X_w(a,b)\exp\left(i\frac{t-b}{a}\right)\, db\ da</math>
This inverse transform suggests that a wavelet should be defined as