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Wavelet Signal Analyzer

Analyze and compress signals using wavelets

Since R2023a


The Wavelet Signal Analyzer app enables visualization, analysis, and compression of 1-D signals using decimated and nondecimated discrete wavelet and wavelet packet transforms. The app plots the decomposition of the signal and its corresponding reconstruction. The app also shows statistics of the decomposition, including the approximate frequency band of each component. With the Wavelet Signal Analyzer app, you can:

  • Access all single-channel, real- and complex-valued 1-D signals in the MATLAB® workspace.

  • Compare decompositions from different analyses by varying the wavelet or the decomposition level.

  • Visualize the time-aligned coefficients.

  • Extend the signal periodically or by reflection before computing the wavelet transform.

  • Apply a global threshold or level-dependent thresholds to the decomposition to compress the signal.

  • Plot the energy for all decomposition levels and display autocorrelations and histograms of the original and compressed coefficients at a specific level.

  • Export decomposition coefficients, compressed coefficients, and compressed signals to the MATLAB workspace.

  • Generate MATLAB scripts to reproduce results in your workspace.

The Wavelet Signal Analyzer app supports single- and double-precision data.

Wavelet Signal Analyzer app

Open the Wavelet Signal Analyzer App

  • MATLAB Toolstrip: On the Apps tab, under Signal Processing and Communications, click the app icon.

  • MATLAB command prompt: Enter waveletSignalAnalyzer.

Programmatic Use

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waveletSignalAnalyzer opens the Wavelet Signal Analyzer app. Once the app initializes, import a signal from your workspace for analysis and compression by clicking Import.

waveletSignalAnalyzer(sig) opens the Wavelet Signal Analyzer app and imports, decomposes, and displays the nondecimated discrete wavelet transform of sig using the modwt function with the sym4 wavelet and default settings.

sig is a variable in the workspace. sig can be:

  • A 1-by-N or N-by-1 real- or complex-valued vector.

  • Single- or double-precision data.


  • To decompose one channel of a multichannel signal, import the channel programmatically. For example, decompose the 10th channel of the multichannel Espiga3 EEG data set using these commands.

    load Espiga3

  • To decompose different 1-D signals simultaneously, run multiple instances of Wavelet Signal Analyzer.

Version History

Introduced in R2023a

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