# Questions tagged [wavelet-analysis]

Questions on the wavelet analysis functions of Mathematica.

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### Continuous Wavelet Transform Coefficients

I am trying to reconstruct the continuous wavelet transform coefficients from Mathematica without using the ContinuousWaveletTransform function. I need to create this reconstruction for my data in a ...
72 views

### How to plot time-frequency evolution based on zero crossings?

In a paper that analyzes the data from GW150914, a time-frequency plot was shown. The paper proposes that, quote: An approximate version of the time-frequency evolution can also be obtained directly ...
123 views

### How to extract data from wavelet scalogram?

I've read several topics here concerning wavelets. Especially this one is very useful where in the answer is explained how to convert default Mathematica scalogram into useful one (with frequency and ...
36 views

### Continuous wavelet transform with complex shannon wavelet [duplicate]

The complex Shannon function is defined as: It seems that Mathematica doesn't support the complex Shannon transform although it supports the real Shannon function. I need the complex Shannon function ...
35 views

### Fourier factor and Fourier transform for wavelet transform [duplicate]

To define the continuous wavelet transform in Mathematica, you need Fourier factor and Fourier transform. I don't understand how to find these two, for example, how can define these two in the haar ...
1 vote
138 views

### Plot wavefronts of Laguerre-Gaussian modes

I am trying to plot wavefronts of Laguerre-Gaussian modes, and want to show the changing number of twists with the change in l values. If anyone has the code or any insights. Kindly help me about it. ...
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### Orthonormal Wavelet functions

The wavelet function "WaveletPsi" is supposed to create an orthonormal basis of some space. Now consider e.g. the following wavelet function: ...
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152 views

### Discrete wavelet transform with complex shannon wavelet

The complex Shannon function is defined as: It seems that Mathematica doesn't support the complex Shannon transform although it supports the real Shannon function. I need the complex Shannon function ...
90 views

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### Image Segmentation for Grid and fence of cage in Frequency Domain

I want to analysis the pattern of this kind of grid of cage, and remove them in frequency domain. The goal image is like that shown by imgFinal, it's not an ...
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216 views

### One dimensional wave equation -numerical vs analitcal solution? [closed]

Recently I have been experimenting with one dimensional wave equation with Dirichlet boundary conditions. So the problem goes like this: I found this formulas in: Qiong-Gui Lin "Yet another ...
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234 views

### Defining a new wavelet (Fibonacci wavelet)

I want to define a new wavelet (Fibonacci wavelet) in the reference. So, I read the tutorial on Wolfram Site, @Jason B. ' s answer, and also @Sektor 's answers. But I still have some problems in my ...
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### Please explain this syntax: GaborWavelet[6]["FourierFactor"]

I've been using Mathematica for some years, yet I'm befuddled by this statement: GaborWavelet[6]["FourierFactor"] It appears to give the center frequency ...
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1k views

### Is there a way to add a cone of influence to waveletscalogram?

This question was asked in 2013, but didn't get an answer. Can Mathematica plot the cone of influence in wavelet analysis. Matlab will do it. Follow up question. Does it make good mathematical ...
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### Cannot take DWT of parsed data

I have some data in foo.tsv, and I would like to take the DiscreteWaveletTransform of one column. My data looks like this: ...
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### Getting rid of "glitches" in DiscreteWaveletTransform-de-noised data

Typical glitch Dear all, I have been using discrete wavelet transforms for de-noising simulated (and real) radiation counting data and from time to time encounter "glitches" in the resulting de-...
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132 views

### Integral of a Wavelet function

I ran into problems integrating a function which contains both an If condition and a Wavelet which is an ...
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### <<WaveletsWavelets Not Found [closed]

please i'm a student and i need help in my project which is based on an already existing program. The problem that the program is ancient( Mathematica 5.0) and doesn't fit with the new versions of ...
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85 views

### WaveletListPlot: Broken in 11.2?

I'm trying to create a WaveletListPlot, following the reference code exactly: ...
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### Solve 1D Wave Equation

I wanna model 1D wave equation and plot it, Here is my try so far, ...
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1 vote
162 views

### Numerical solution to approximate the singular integration using collocation method

I am working to solve "numerically" the following integral equation IE: u[x]=f[x]+Integrate[(1/(x-t)^(1/4))*u[t],{t,0,x}]+Integrate[(1/(x-t)^(1/4))*u[t],{t,0,1}] ...
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### Coefficients of continuous wavelet transform

I am fiddling with wavelet coefficients in Mathematica, and for simplicty only a real valued Wavlet. Lets say we have the data: ...
128 views

### Getting errors NIntegrate::nlim and NIntegrate::slwcon [closed]

Here is the modified question: First: Define phi[x_]:=Piecewise[{{1, 0 <= x < 1}}, 0] ...
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1 vote
108 views

### Revert image fusion using discrete wavelet transform

How can I extract a hidden image using discrete wavelet transform? I have used the function ImageFusion from this site to hide an image inside another one. ...
176 views

### Integrating a function containing a wavelet

How do I evaluate the integral c? ...
210 views

### How to extract a single image from the output of the DiscreteWaveletTransform[]?

So, I use the following code to carry out the discrete wavelet transform on an image of Lena. I am interested in then doing some changes to a single image out of the obtained 4. How do I extract any ...
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1 vote
163 views

### wavelet fourier transform

I want to do wavelet Fourier transform of my data but I have few doubts in this. 1)first of all what is octive and voice command here when i am changing value according to that my plot is changing but ...
1 vote
392 views

### Comparison of Discrete Cosine Transform and Discrete Wavelet Transform

I would like to compare the sorted coefficients of the Discrete Cosine Transform with that of the Discrete Wavelet Transform using the Haar wavelets. From theory, the discrete wavelet transform offers ...
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### Computing FundamentalFrequency

How does Mathematica use AudioLocalMeasurements to compute the fundamental frequency? Is there any formula? I can't seem to find what method Mathematica makes use ...
387 views

### Wavelet filter artifact

I would like to denoise some data using wavelet filters. My current approach is to employ the stationary wavelet transform with Haar wavelets. However, this leads to undesirable artifacts at the top ...
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### How to detect the singular value in 3-dimension with wavelet analysis

Actually this question is related with this post,but this is about point of 3-dimension ...
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1 vote
201 views

### How to detect the singular value with wavelet analysis

I have a series data data=Uncompress[ FromCharacterCode[Flatten[ImageData[Import["https://i.sstatic.net/ApipY.png"], "Byte"]]]]; We can show it ...
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427 views

### How to calculate the amount of offset about two list

You can get my data by this code {data1, data2} = Uncompress[FromCharacterCode@ Flatten[ImageData[Import["https://i.sstatic.net/ShSMY.png"], "Byte"]]]; We can ...
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1 vote
231 views

### Find wavelet transform coefficients in L1 norm [closed]

For my masters task I have to perform a Haar wavelet transform using an L1 norm. But Mathematica's built-in wavelet library can work only with L2 norm space. I tried to do this: ...
145 views

### Why does Continuous Wavelet Transform have phase information at high frequencies?

I'm playing around with ContinuousWaveletTransform using a sine wave of a constant frequency: ...
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### How to detect discolorations in an image?

I'm evaluating the technical quality of an images and I'd like to scan it for defects from dirty sensors. Are there any filters to quickly detect a blob of discoloration? Here are a few examples:
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### How to generate a Wavelet Matrix?

The Wavelet Matrix, also called the Haar matrix, is very useful. We can find some useful information in MathWorld on how to generate it, but this document is too hard for me. From my reading of the ...
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### Detrending a time-series by means of Discrete Wavelet Transform

I plot a time-series for observation as you can see in the plot: I tried to detrend the time series by 3 different approaches which are: 1) differences, 2) detrended fluctuation analysis, and 3) ...
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1 vote
135 views

### How to recover data from a DiscreteWaveletTransform with Battle-Lemarie Wavelets?

The question is why can data be recovered perfectly from a discrete wavelet transform with a Haar wavelet but not with some Battle-Lemarie wavelets? A simple example with the ...
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### Modified WaveletImagePlot

When performing Wavelet Transform ...
511 views

### How to obtain amplitude and phase of tidal data using wavelets

I have a time series of tidal data for one month and success with identifying tidal characteristic such as semidiurnal or diurnal spring and neap position power spectrum However, I don't have ...
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### InverseWaveletTransform not recreating the original image exactly

I am trying to do DWT steganography. I first obtain the DiscreteWaveletTransform of the image as follows ...
1 vote
338 views

### Wavelet Data Visualization (modus and phase) ListPlot [closed]

Due to ContinuousWaveletTransform[...] I can obtain information about wavelet-coefficient for example ...
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664 views

### How to define a new wavelet type?

I have a problem in understanding how to create my own wavelets in Mathematica's wavelet framework. There is a tutorial. I have read the tutorial, but I don’t understand what exactly is needed to ...
• 233
3k views

### Create "Ostagram" like Images using Wavelet Transforms

I am trying to make an "ostagram" like image using wavelet transforms and image keypoints. See the following link: https://www.facebook.com/ostagram/ This is done using neural networks, which I at ...
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### Detecting components in timeseries

I'm looking at this sequence of values: I'd like to detect the points where the center of the time-series shifts (around x=1000 and x=2000). Many of the transforms and smoothing methods I have tried ...
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1 vote
132 views

### Problem with DiscreteWaveletTransform for DaubechiesWavelet

I am trying to use Mathematica's wavelet transform. In preparation I entered: ...
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1 vote
112 views

### InverseWaveletTransform of a list of rules

I want to extract coefficient images from a DiscreteWaveletTransform and replace them by modified images of the same dimensions. However, when I use ...
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