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What are the Matlab functions that are available for the wavelet operation on images? 

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Proceedings ArticleDOI
J. Akhtar, Muhammad Younus Javed 
01 Jan 2006
10 Citations
This analysis will help in choosing the wavelet for decomposition of images as per their application
Open accessJournal ArticleDOI
Minh N. Do, Martin Vetterli 
734 Citations
Numerical results show that the FRIT is more effective than the wavelet transform in approximating and denoising images with straight edges.
Several examples of the wavelet analysis applied to various satellite images demonstrate the feasibility of this technique for coastal monitoring.
The proposed method establishes a multifractal analysis framework of such images based on a new multiresolution indicator, called the maximum wavelet coefficient, derived from the wavelet leaders.
The two component Harr mother wavelet was found to be suitable for the fast computations of the interpolated images and their subsequent versions.
It is shown that using a particular form of the son wavelet function, results are improved compared to those obtained with the traditionally Morlet wavelet function.
Our algorithm uses the Marr, or "Mexican Hat" wavelet function, but may be adapted for use with other wavelet functions.
Our numerical results show that the reconstructed images from our wavelet algorithms are better than that from the Tikhonov least-squares approach.

Related Questions

What are the advantages of the wavelet transform over the Fourier transform?4 answersThe wavelet transform has several advantages over the Fourier transform. Firstly, the wavelet transform provides a multi-resolution analysis, allowing for the examination of signals at different scales or frequencies. This is in contrast to the Fourier transform, which only provides a global frequency analysis. Secondly, the wavelet transform has a constant relative bandwidth, meaning that it can accurately represent both high and low frequency components of a signal. In comparison, the Fourier transform has a fixed frequency resolution, which may not capture all the details of a signal. Additionally, the wavelet transform is able to represent local characteristics of signals in both the time and frequency domains, making it a powerful tool for signal analysis. These advantages make the wavelet transform suitable for a wide range of applications, including multimedia processing, signal denoising, and wireless communications.
What is the wavelet transform?4 answersThe wavelet transform is a time-frequency analysis method that combines the time and frequency (or scale) domains. It has the ability to represent the local characteristics of signals in both time and frequency domains, making it a powerful tool for signal analysis. The wavelet transform is particularly advantageous compared to other time-frequency representations, such as the short-time Fourier transform, due to its ability to accommodate frequency that evolves or changes with time. It can effectively remove noise interference from signals, making it useful in applications such as EEG signal analysis. The selection of the right wavelet system is crucial for implementing the spectrum sensing function in cognitive radio networks, as it affects communication performance and continuity. The wavelet transform has also been applied in processing gamma-ray spectra, where it can accurately detect peaks and remove fluctuations and background from the spectrum.
Which types of wavelet are the best?4 answersThe best types of wavelet depend on the specific application. In the context of business cycle analysis in Iran, the study found that biorthogonal wavelets, particularly bior2.2, bior3.1, bior2.6, bior5.5, bior1.1, bior1.5, and bior1.3, provided the highest quality of decomposition and smoothing. For cognitive EEG classification, the Boir 2.4 wavelet type yielded the best true positive rate. In the analysis of image decomposition, Haar and Meyer wavelets demonstrated the best quality of restored image, while Daubechies wavelets, symplets, and coiflets had higher compression index. In the context of dynamic systems engineering, wavelets can be classified into orthogonal, biorthogonal, and pseudo types, with applications in vibrations analysis and systems and control analysis. For speech enhancement, the DWT Coif wavelet with soft thresholding was found to be the best for reducing noise and enhancing speech and audio signal quality.
What are the different types of transforms that can be performed in Matlab?4 answersDifferent types of transforms that can be performed in Matlab include: multimodal dispersion image generation using three different transformation techniques, High Pass Filter-HPF and Wavelet À trous transforms for satellite image fusion, linear transformations such as Euler's Transformations, Euler-Maclaurin Summation Formula, and Levin's transform for accurate evaluation of infinite series and integrals, discrete multivariate transforms induced by multivariate sine functions for interpolation and orthogonal polynomials, and transforms used with exponential smoothing for better forecasting.
How do you do wavelet analysis in R?18 answers
What is wavelet transform coding?9 answers

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