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plotdt

Plot dual-tree or double-density wavelet transform

Description

example

plotdt(wt) plots the coefficients of the 1-D or 2-D wavelet filter bank decomposition, wt.

Examples

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Plot the complex dual-tree wavelet transform of the noisy Doppler signal.

Load the noisy Doppler signal. Obtain the complex dual-tree wavelet transform down to level 4.

load noisdopp;
wt = dddtree('cplxdt',noisdopp,4,'dtf1');

Plot the coefficients.

plotdt(wt)

Figure CPLXDT contains 10 axes. Axes 1 with title Type of TREE: CPLXDT contains an object of type line. Axes 2 contains an object of type line. Axes 3 contains an object of type line. Axes 4 contains an object of type line. Axes 5 contains an object of type line. Axes 6 contains an object of type line. Axes 7 contains an object of type line. Axes 8 contains an object of type line. Axes 9 contains an object of type line. Axes 10 contains an object of type line.

Plot the complex oriented dual-tree wavelet transform of an image.

Load the xbox image. Obtain the complex oriented dual-tree wavelet transform down to level 3.

load xbox;
wt = dddtree2('cplxdt',xbox,3,'dtf1');

Plot the coefficients.

plotdt(wt)

Figure CPLXDT - LEVEL 3 contains 40 axes and other objects of type uicontrol, uipanel. Axes 1 with title C_{111} contains an object of type image. Axes 2 with title C_{121} contains an object of type image. Axes 3 with title C_{112} contains an object of type image. Axes 4 with title C_{122} contains an object of type image. Axes 5 with title C_{211} contains an object of type image. Axes 6 with title C_{221} contains an object of type image. Axes 7 with title C_{212} contains an object of type image. Axes 8 with title C_{222} contains an object of type image. Axes 9 with title C_{311} contains an object of type image. Axes 10 with title C_{321} contains an object of type image. Axes 11 with title C_{312} contains an object of type image. Axes 12 with title C_{322} contains an object of type image. Axes 13 with title C_{111} contains an object of type image. Axes 14 with title C_{121} contains an object of type image. Axes 15 with title C_{112} contains an object of type image. Axes 16 with title C_{122} contains an object of type image. Axes 17 with title C_{211} contains an object of type image. Axes 18 with title C_{221} contains an object of type image. Axes 19 with title C_{212} contains an object of type image. Axes 20 with title C_{222} contains an object of type image. Axes 21 with title C_{311} contains an object of type image. Axes 22 with title C_{321} contains an object of type image. Axes 23 with title C_{312} contains an object of type image. Axes 24 with title C_{322} contains an object of type image. Axes 25 with title C_{111} contains an object of type image. Axes 26 with title C_{121} contains an object of type image. Axes 27 with title C_{112} contains an object of type image. Axes 28 with title C_{122} contains an object of type image. Axes 29 with title C_{211} contains an object of type image. Axes 30 with title C_{221} contains an object of type image. Axes 31 with title C_{212} contains an object of type image. Axes 32 with title C_{222} contains an object of type image. Axes 33 with title C_{311} contains an object of type image. Axes 34 with title C_{321} contains an object of type image. Axes 35 with title C_{312} contains an object of type image. Axes 36 with title C_{322} contains an object of type image. Axes 37 with title C_{11} contains an object of type image. Axes 38 with title C_{21} contains an object of type image. Axes 39 with title C_{12} contains an object of type image. Axes 40 with title C_{22} contains an object of type image.

Select the desired level detail coefficients from the drop-down list.

Input Arguments

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Wavelet transform, returned as a structure from dddtree or dddtree2 with these fields:

Type of wavelet decomposition (filter bank), specified as one of 'dwt', 'ddt', 'realdt', 'cplxdt',, 'realdddt', or 'cplxdddt'. 'realdt' and 'realdddt' are only valid for the 2-D wavelet transform. The type, 'dwt', is a critically sampled (nonredundant) discrete wavelet transform for 1-D data or 2-D images. The other decomposition types are oversampled wavelet transforms. For details about transform types see dddtree for 1-D wavelet transforms and dddtree2 for 2-D wavelet transforms.

Level of the wavelet decomposition, specified as a positive integer.

Decomposition (analysis) and reconstruction (synthesis) filters, specified as a structure with these fields:

First level decomposition filters specified as an N-by-2 or N-by-3 matrix for single-tree wavelet transforms, or a 1-by-2 cell array of two N-by-2 or N-by-3 matrices for dual-tree wavelet transforms. The matrices are N-by-3 for the double-density wavelet transforms. For an N-by-2 matrix, the first column of the matrix is the scaling (lowpass) filter and the second column is the wavelet (highpass) filter. For an N-by-3 matrix, the first column of the matrix is the scaling (lowpass) filter and the second and third columns are the wavelet (highpass) filters. For the dual-tree transforms, each element of the cell array contains the first-stage analysis filters for the corresponding tree.

Analysis filters for levels > 1, specified as an N-by-2 or N-by-3 matrix for single-tree wavelet transforms, or a 1-by-2 cell array of two N-by-2 or N-by-3 matrices for dual-tree wavelet transforms. The matrices are N-by-3 for the double-density wavelet transforms. For an N-by-2 matrix, the first column of the matrix is the scaling (lowpass) filter and the second column is the wavelet (highpass) filter. For an N-by-3 matrix, the first column of the matrix is the scaling (lowpass) filter and the second and third columns are the wavelet (highpass) filters. For the dual-tree transforms, each element of the cell array contains the analysis filters for the corresponding tree.

First-level reconstruction filters, specified as an N-by-2 or N-by-3 matrix for single-tree wavelet transforms, or a 1-by-2 cell array of two N-by-2 or N-by-3 matrices for dual-tree wavelet transforms. The matrices are N-by-3 for the double-density wavelet transforms. For an N-by-2 matrix, the first column of the matrix is the scaling (lowpass) filter and the second column is the wavelet (highpass) filter. For an N-by-3 matrix, the first column of the matrix is the scaling (lowpass) filter and the second and third columns are the wavelet (highpass) filters. For the dual-tree transforms, each element of the cell array contains the first-stage synthesis filters for the corresponding tree.

Reconstruction filters for levels > 1, specified as an N-by-2 or N-by-3 matrix for single-tree wavelet transforms, or a 1-by-2 cell array of two N-by-2 or N-by-3 matrices for dual-tree wavelet transforms. The matrices are N-by-3 for the double-density wavelet transforms. For an N-by-2 matrix, the first column of the matrix is the scaling (lowpass) filter and the second column is the wavelet (highpass) filter. For an N-by-3 matrix, the first column of the matrix is the scaling (lowpass) filter and the second and third columns are the wavelet (highpass) filters. For the dual-tree transforms, each element of the cell array contains the first-stage synthesis filters for the corresponding tree.

Wavelet transform coefficients, specified as a 1-by-(level+1) cell array of matrices. The size and structure of the matrix elements of the cell array depend on the type of wavelet transform and whether the decomposition is 1-D or 2-D. For a 1-D wavelet transform, the coefficients are organized by transform type as follows:

  • 'dwt'cfs{j}

    • j = 1,2,...level is the level.

    • cfs{level+1} are the lowpass, or scaling, coefficients.

  • 'ddt'cfs{j}(:,:,k)

    • j = 1,2,... level is the level.

    • k = 1,2 is the wavelet filter.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'cplxdt'cfs{j}(:,:,m)

    • j = 1,2,... level is the level.

    • m = 1,2 are the real and imaginary parts.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'realdddt'cfs{j}(:,:,d,k)

    • j = 1,2,... level is the level.

    • d = 1,2,3 is the orientation.

    • k = 1,2 is the wavelet transform tree.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'cplxdddt'cfs{j}(:,:,d,k,m)

    • j = 1,2,... level is the level.

    • k = 1,2 is the wavelet transform tree.

    • m = 1,2 are the real and imaginary parts.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

For a 2-D wavelet transform, the coefficients are organized by transform type as follows:

  • 'dwt'cfs{j}(:,:,d)

    • j = 1,2,... level is the level.

    • d = 1,2,3 is the orientation.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'ddt'cfs{j}(:,:,d)

    • j = 1,2,... level is the level.

    • d = 1,2,3,4,5,6,7,8 is the orientation.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'realddt'cfs{j}(:,:,d,k)

    • j = 1,2,... level is the level.

    • d = 1,2,3 is the orientation.

    • k = 1,2 is the wavelet transform tree.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'cplxdt'cfs{j}(:,:,d,k,m)

    • j = 1,2,... level is the level.

    • d = 1,2,3 is the orientation.

    • k = 1,2 is the wavelet transform tree.

    • m = 1,2 are the real and imaginary parts.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'realdddt'cfs{j}(:,:,d,k)

    • j = 1,2,... level is the level.

    • d = 1,2,3 is the orientation.

    • k = 1,2 is the wavelet transform tree.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

  • 'cplxdddt'cfs{j}(:,:,d,k,m)

    • j = 1,2,... level is the level.

    • d = 1,2,3 is the orientation.

    • k = 1,2 is the wavelet transform tree.

    • m = 1,2 are the real and imaginary parts.

    • cfs{level+1}(:,:) are the lowpass, or scaling, coefficients.

Introduced in R2013b