Available Wavelet Families
There are two tiers of wavelet types in this package. The most abstract is the ContWave
type, representing a class of wavelets. This is split into several strictly continuous wavelets, and a ContOrtho<:ContWave
type, which is a supertype of continuous versions of the orthogonal wavelets defined in Wavelets.jl.
ContinuousWavelets.ContWave
— TypeContWave{Boundary,T}
The abstract type encompassing the various types of wavelets implemented in the package. The abstract type has parameters Boundary<:WaveletBoundary
and T<:Number
, which gives the element output type. Each has both a constructor, and a default predefined entry. These are:
Morlet
: A complex approximately analytic wavelet that is just a frequency domain Gaussian with mean subtracted.Morlet(σ::T) where T<: Real
.σ
gives the frequency domain variance of the mother Wavelet. Asσ
goes to zero, all of the information becomes spatial. Default ismorl
which has $\sigma=2\pi$.$\psi\hat(\omega) \propto \textrm{e}^{-\frac{\sigma^2}{2}}\big(\textrm{e}^{-(\sigma - \omega)^2} -\textrm{e}^{\frac{\omega^2-\sigma^2}{2}}\big)$
Paul{N}
: A complex analytic wavelet, also known as Cauchy wavelets.pauln
for n in1:20
e.g.paul5
$\psi\hat(\omega) \propto \chi_{\omega \geq 0} \omega^N\textrm{e}^{-\omega}$
Dog{N}
: Derivative of a Gaussian, where N is the number of derivatives.dogn
forn
in0:6
. The Sombrero/mexican hat/Marr wavelet isn=2
.$\psi\hat(\omega) \propto \omega^N\textrm{e}^{-\frac{\omega^2}{2}}$
ContOrtho{OWT}
. OWT is some orthogonal wavelet of typeOrthoWaveletClass
from Wavelets.jl. This uses an explicit construction of the mother wavelet for these orthogonal wavelets to do a continuous transform. Constructed viaContOrtho(o::W)
whereo
is from Wavelets.jl. Alternatively, you can get them directly asContOrtho
objects via:cHaar
Haar WaveletscBeyl
Beylkin WaveletscVaid
Vaidyanathan WaveletscDbn
Daubhechies Wavelets. n ranges from1:Inf
cCoifn
Coiflets. n ranges from2:2:8
cSymn
Symlets. n ranges from4:10
cBattn
Battle-Lemarie wavelets. n ranges from2:2:6
Above are examples of every mother wavelet family defined in this package; the only analytic and/or complex wavelets are the Morlet
and the Paul
wavelet families. Once you have chosen a type of wavelet, this is used to construct the more specific CWT, which specifies more details of the transform, such as frequency spacing, whether to include an averaging filter or not, a frame upper bound, etc.