The proceedings contain 47 papers from the conference of SPIE: wavelets-applications in signal and imageprocessingix. The topics discussed include: image restoration using statistical wavelet models;noise selection ...
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The proceedings contain 47 papers from the conference of SPIE: wavelets-applications in signal and imageprocessingix. The topics discussed include: image restoration using statistical wavelet models;noise selection approach to image restoration;adaptive wavelet lifting for image retrieval;tight frame approximations for gabor and wavelet frames;inverse-constrained projection filters;topological obstructions to localization results and embedding multiresolution spline structures.
The correlation of the wavelet shape and the characteristic ECG section has been confirmed, and wavelets for the identification of P-, R-, and T waves have been experimentally established. An algorithm for identifying...
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ISBN:
(数字)9798331518752
ISBN:
(纸本)9798331518769
The correlation of the wavelet shape and the characteristic ECG section has been confirmed, and wavelets for the identification of P-, R-, and T waves have been experimentally established. An algorithm for identifying R waves in an ECG has been developed and its operability has been verified. Using the algorithm developed, a graph of the dynamics of the heartbeat period is plotted as a function of time (period number). To identify the P and T waves, the wavelet image of the real ECG is constructed, and the presence of distortion of the shape of this image due to the influence of QRS complex and neighboring waves is established. Computer removal (filtering) of QRS complexes from the ECG is carried out, wavelet image of the remaining part is calculated. The possibility of determining the positions of the maximum P- and T-waves has been established from the wavelet image of the filtered ECG. The theoretical and practical value of this study consists in a new direction of wavelet analysis of cardiac signals, by successively applying several wavelets of a special form, to identify characteristic sections of the ECG in order to improve diagnostics. The proposed method also assumes intermediate filtering of the identified sections when moving from wavelet to wavelet. The development was carried out within the framework of computer generation of arrays of digital functions of the state of the heart, suitable for training artificial intelligence systems, and diagnostics using such systems. The practical results obtained can be applied in the development of a digital expert diagnostic system or a specific technical device.
Wavelet signalprocessing has demonstrated remarkable capabilities in reducing noise, achieving better resolution through edge detection and increasing data transmission by means of data compression. While wavelets ar...
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ISBN:
(纸本)0819441929
Wavelet signalprocessing has demonstrated remarkable capabilities in reducing noise, achieving better resolution through edge detection and increasing data transmission by means of data compression. While wavelets are digital, another field, Optical Phase Conjugation (OPC), is analog and has been applied to similar problems: signal and image distortion reduction and optical data storage. wavelets have been applied to optical solitons, laser beam diagnostics, diode laser arrays, interferometry and optical correlators. Wavelet signalprocessing will be applied to Optical Phase Conjugation to examine laser beam interaction in nonlinear crystals and remove distortion from input and output laser beams.
The key element in the design of fast algorithms in numerical analysis and signalprocessing is the selection of an efficient approximation for the functions and operators involved. In this talk we will consider appro...
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ISBN:
(纸本)0819441929
The key element in the design of fast algorithms in numerical analysis and signalprocessing is the selection of an efficient approximation for the functions and operators involved. In this talk we will consider approximations using wavelet and multiwavelet bases as well as a new type of approximation for bandlimited functions using exponentials obtained via Generalized Gaussian quadratures. Analytically, the latter approximation corresponds to using the basis of the Prolate Spheroidal Wave functions. We will briefly comment on the future development of approximation techniques and the corresponding fast algorithms.
Exploiting the geometrical interpretation of the Haar transform as a rotation of the coordinate system by an angle pi/4, a new Haar-like transform is proposed which rotates the co-ordinate system by an angle which dep...
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ISBN:
(纸本)0819441929
Exploiting the geometrical interpretation of the Haar transform as a rotation of the coordinate system by an angle pi/4, a new Haar-like transform is proposed which rotates the co-ordinate system by an angle which depends on the data. This data dependent transform gives better compression ratios for both signals and images than the Haar transform.
This paper deals with a restoration (both denoising and deblurring) method. For instance in the case of denoising, this latter is only a small modification from the usual wavelet thresholding. However, it has the sign...
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ISBN:
(纸本)0819441929
This paper deals with a restoration (both denoising and deblurring) method. For instance in the case of denoising, this latter is only a small modification from the usual wavelet thresholding. However, it has the significant advantage to allow the use of several bases in such a way that we select what is considered as information by a basis or another basis or another basis, and so on for as many bases as we want. The computational cost of the method is mainly the computation of the coordinates of the signal (or image) in the bases.
The Lifting Scheme (LS) is a very efficient implementation of the Discrete Wavelet transform (DWT). In this work we compute the arithmetic gain realized when the LS is used instead of conventional filter banks. It is ...
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ISBN:
(纸本)0819441929
The Lifting Scheme (LS) is a very efficient implementation of the Discrete Wavelet transform (DWT). In this work we compute the arithmetic gain realized when the LS is used instead of conventional filter banks. It is shown that contrary to was was presented in the original work from Sweldens again of four is possible. However the LS should be used with care as it can increase the memory bandwidth. Some implementations are presented together with their impact on the bandwidth.
This work provides a new approach to estimate the parameters of a semi-parametric generalized linear model in the wavelet domain. The method is illustrated with the problem of detecting significant changes in fMRI sig...
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ISBN:
(纸本)0819441929
This work provides a new approach to estimate the parameters of a semi-parametric generalized linear model in the wavelet domain. The method is illustrated with the problem of detecting significant changes in fMRI signals that are correlated to a stimulus time course. The fMRI signal is described as the sum of two effects : a smooth trend and the response to the stimulus. The trend belongs to a subspace spanned by large scale wavelets. We have developed a scale space regression that permits to carry out the regression in the wavelet domain while omitting the scales that are contaminated by the trend. Experiments with fMRI data demonstrate that our approach can infer and remove drifts that cannot be adequately represented with low degree polynomials. Our approach results in a noticeable improvement by reducing the false positive rate and increasing the true positive rate.
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