the selection of most suitable mother wavelet function is still an open research problem in various signal and imageprocessingapplications. this paper presents a comparative study of different wavelet families (Daub...
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the selection of most suitable mother wavelet function is still an open research problem in various signal and imageprocessingapplications. this paper presents a comparative study of different wavelet families (Daubechies, Symlets, Coiflets, and Biorthogonal) for analysis of wrist motions from electromyography (EMG) signals. EMG signals are decomposed into three levels using discrete wavelet packet transform. From the decomposed EMG signals, root mean square (RMS) value, autoregressive (AR) model coefficients (4th order) and waveform length (WL) are extracted. Two data projection methods such as principal component analysis (PCA) and linear disciminant analysis (LDA) are used to reduce the dimensionality of the extracted features. Probabilistic neural network (PNN) and general regression neural network (GRNN) are employed to classify the different types of wrist motions, which gives a promising accuracy of above 99%. From the analysis, we inferred that 'Biorthogonal' and 'Coiflets' wavelet families are more suitable for accurate classification of EMG signals of different wrist motions. (C) 2012 Elsevier Ltd. All rights reserved.
this paper describes an approach for accomplishing sub- octave wavelet analysis and its discrete implementation for noise reduction and feature enhancement. Sub-octave wavelet transforms allow us to more closely chara...
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Blocking artifacts are the most objectionable drawback of block-based image and video coders. We describe a novel technique for removing blocking artifacts via multiscale edge processing. the new technique exploits th...
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ISBN:
(纸本)0819422134
Blocking artifacts are the most objectionable drawback of block-based image and video coders. We describe a novel technique for removing blocking artifacts via multiscale edge processing. the new technique exploits the advantages of an invertible multiscale edge representation from which the block edges can be easily identified and removed. By virtue of the multiscale edge processing one is able to deblock images effectively without blurring perceptually important features or introducing new artifacts. We present the deblocking algorithm with experimental results and a discussion.
Volume data such as those acquired by magnetic resonance imaging techniques can be compressed efficiently using the wavelet transform. wavelet compression methods need to retain boththe value and the location of the ...
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ISBN:
(纸本)0819422134
Volume data such as those acquired by magnetic resonance imaging techniques can be compressed efficiently using the wavelet transform. wavelet compression methods need to retain boththe value and the location of the significant coefficients. We present experimental results demonstrating the use of zerotree encoding methods in wavelet compression can enhance the ability to further compress volume data.
Orthogonal, semiorthogonal and biorthogonal wavelet bases are special cases of oblique multiwavelet bases. One of the advantage of oblique multiwavelets is the flexibility they provide for constructing bases with cert...
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ISBN:
(纸本)0819422134
Orthogonal, semiorthogonal and biorthogonal wavelet bases are special cases of oblique multiwavelet bases. One of the advantage of oblique multiwavelets is the flexibility they provide for constructing bases with certain desired shapes and/or properties. the decomposition of a signal in terms of oblique wavelet bases is still a perfect reconstruction filter bank. In this paper, we present several examples that show the similarity and differences between the oblique and other types of wavelet bases. We start withthe Haar multiresolution to illustrate several examples of oblique wavelet bases, and then use the Cohen-Daubechies-Plonka multiscaling function to construct several oblique multiwavelets.
In this paper, medical image compression technique is presented based on adaptive Scan wavelet Difference Reduction (ASWDR). It helps to save the storage space and transmission bandwidth of tele-healthcare system. the...
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ISBN:
(纸本)9781509027972
In this paper, medical image compression technique is presented based on adaptive Scan wavelet Difference Reduction (ASWDR). It helps to save the storage space and transmission bandwidth of tele-healthcare system. the presented compression scheme has evaluated for different ultrasound image of different cases. the ASWDR technique is exploited with different wavelet filters and obtained the different efficiency of compression as per distinctive sparse characteristics. However, the performance of presented compression scheme is evaluated with fidelity assessments as well as human vision perception for compression and reconstruction. As seen the results, compression of the image is obtained up to 45:1 with 99% of structural similarity of the original and compressed image.
Breast cancer is known as one of the important diseases in medical science in which its early detection can reduce mortality rate and improve the survival rate of the patients. A World Health Organization (WHO) estima...
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ISBN:
(纸本)9781538652398
Breast cancer is known as one of the important diseases in medical science in which its early detection can reduce mortality rate and improve the survival rate of the patients. A World Health Organization (WHO) estimates that in 2015, at least 561 thousand women will die of breast cancer throughout the world. Early detection of cancer can reduce the rate of mortality, so it would be useful to develop a computer-assisted method to help differentiate between masses or tumors based on characteristics extracted from the part of interest in mammography. In this article, the idea is to combine descriptors of different nature for digital mammography: texture and shape. the texture descriptor (wavelet), which is often used for the classification of mammary masses and the shape descriptor SMD (Spiculated Mass Descriptor), which is very effective from the point of view of robustness to noise, invariance to geometric transformations and characterization of masses breast.
the optics of satellite cameras as well as the satellite movement create a blurring effect to which is added a noise due to the electronics of the CCD captors. We introduce a deconvolution algorithm which is regulariz...
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ISBN:
(纸本)0819422134
the optics of satellite cameras as well as the satellite movement create a blurring effect to which is added a noise due to the electronics of the CCD captors. We introduce a deconvolution algorithm which is regularized with a hard thresholding technic, in a wavelet frame. the restoration procedure is fast and provides good metrical and perceptual results.
We introduce a general framework for computing the continuous wavelet transform (CWT). Included in this framework is an FFT implementation as well as fast algorithms which achieve O(1) complexity per wavelet coefficie...
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ISBN:
(纸本)0819422134
We introduce a general framework for computing the continuous wavelet transform (CWT). Included in this framework is an FFT implementation as well as fast algorithms which achieve O(1) complexity per wavelet coefficient. the general approach that we present allows a straight forward comparison among a large variety of implementations. In our framework, computation of the CWT is viewed as convolving the input signal withwavelet templates that are the oblique projection of the ideal wavelets into one subspace orthogonal to a second subspace. We present this idea and discuss and compare particular implementations.
We present examples of a new type of wavelet basis functions that are orthogonal across shifts, but not across scales. the analysis functions are low order splines while the synthesis functions are polynomial splines ...
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ISBN:
(纸本)0819422134
We present examples of a new type of wavelet basis functions that are orthogonal across shifts, but not across scales. the analysis functions are low order splines while the synthesis functions are polynomial splines of higher degree n2. the approximation power of these representations is essentially as good as that of the corresponding Battle- Lemarie orthogonal wavelet transform, withthe difference that the present wavelet synthesis filters have a much faster decay. this last property, together withthe fact that these transformation s are almost orthogonal, may be useful for image coding and data compression.
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