Wavelet Toolbox

One-Dimensional Variance Adaptive Thresholding of Wavelet Coefficients

This section takes you through the features of local thresholding of wavelet coefficients for one-dimensional signals or data. This capability is available through graphical interface tools throughout the MATLAB Wavelet Toolbox:

• Wavelet De-noising 1-D
• Wavelet Compression 1-D
• SWT De-noising 1-D
• Regression Estimation 1-D
• Density Estimation 1-D

This tool allows you to define, level by level, time-dependent (x-axis-dependent) thresholds, and then increase the capability of the de-noising strategies handling nonstationary variance noise. More precisely, the model assumes that the observation is equal to the interesting signal superimposed on noise. The noise variance can vary with time. There are several different variance values on several time intervals. The values as well as the intervals are unknown. This section will use one of the graphical interface tool (SWT De-noising 1-D) to illustrate this capability. The behavior of all the above-mentioned tools is similar.

Importing and Exporting Information from the Graphical Interface

One-Dimensional Local Thresholding for De-noising Using the Graphical Interface

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