CDFWavelet

CDFWavelet[]

represents a Cohen–Daubechies–Feauveau wavelet of type "9/7".

CDFWavelet["type"]

represents a Cohen–Daubechies–Feauveau wavelet of type "type".

Details

  • CDFWavelet defines a set of biorthogonal wavelets.
  • The following "type" forms can be used:
  • "5/3"used in lossless JPEG2000 compression
    "9/7"used in lossy JPEG2000 compression
  • The scaling function () and wavelet function () have compact support. The functions are symmetric.
  • CDFWavelet can be used with such functions as DiscreteWaveletTransform, WaveletPhi, etc.

Examples

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Basic Examples  (3)

Scaling function:

Wavelet function:

Filter coefficients:

Scope  (16)

Basic Uses  (10)

Compute primal lowpass filter coefficients:

Dual lowpass filter coefficients:

Primal highpass filter coefficients:

Dual highpass filter coefficients:

Lifting filter coefficients:

Generate function to compute lifting wavelet transform:

Primal scaling function:

Dual scaling function:

Plot scaling function using different levels of recursion:

Primal wavelet function:

Dual wavelet function:

Plot scaling function using different levels of recursion:

Wavelet Transforms  (5)

Compute a DiscreteWaveletTransform:

View the tree of wavelet coefficients:

Get the dimensions of wavelet coefficients:

Plot the wavelet coefficients:

Compute a DiscreteWaveletPacketTransform:

View the tree of wavelet coefficients:

Get the dimensions of wavelet coefficients:

Plot the wavelet coefficients:

Compute a StationaryWaveletTransform:

View the tree of wavelet coefficients:

Get the dimensions of wavelet coefficients:

Plot the wavelet coefficients:

Compute a StationaryWaveletPacketTransform:

View the tree of wavelet coefficients:

Get the dimensions of wavelet coefficients:

Plot the wavelet coefficients:

Compute a LiftingWaveletTransform:

View the tree of wavelet coefficients:

Get the dimensions of wavelet coefficients:

Plot the wavelet coefficients:

Higher Dimensions  (1)

Multivariate scaling and wavelet functions are products of univariate ones:

Properties & Relations  (16)

Lowpass filter coefficients sum to unity; :

Highpass filter coefficients sum to zero; :

Dual lowpass filter coefficients sum to unity; :

Dual highpass filter coefficients sum to zero; :

Scaling function integrates to unity; :

Dual scaling function integrates to unity; :

Wavelet function integrates to zero; :

Dual wavelet function integrates to zero; :

satisfies the recursion equation :

Plot the components and the sum of the recursion:

satisfies the recursion equation :

Plot the components and the sum of the recursion:

satisfies the recursion equation :

Plot the components and the sum of the recursion:

satisfies the recursion equation :

Plot the components and the sum of the recursion:

Frequency response for is given by :

The filter is a lowpass filter:

Fourier transform of is given by :

Frequency response for is given by :

The filter is a dual lowpass filter:

Fourier transform of is given by :

Frequency response for is given by :

The filter is a lowpass filter:

Fourier transform of is given by :

Frequency response for is given by :

The filter is a lowpass filter:

Fourier transform of is given by :

Neat Examples  (2)

Plot translates and dilations of scaling function:

Plot translates and dilations of wavelet function:

Introduced in 2010
 (8.0)