In this paper, wavelet shrinkage techniques that make use of wavelets defined on quincunx grid are explored in comparison with techniques involving wavelets defined on separable grid In order to better exploit the adv...
详细信息
ISBN:
(纸本)951227065X
In this paper, wavelet shrinkage techniques that make use of wavelets defined on quincunx grid are explored in comparison with techniques involving wavelets defined on separable grid In order to better exploit the advantages of the nonseparable transform and to surpass certain disadvantages of quincunxwavelets, the empirical wavelet-domain Wiener filtering that combines separable and quincunxwavelets is additionally investigated.
wavelets, which are a new mathematical tool for data representation, are discussed. wavelets are efficient in reducing the number of parameters in the representation. Efficient representation of data facilitates proce...
详细信息
ISBN:
(纸本)0769521789
wavelets, which are a new mathematical tool for data representation, are discussed. wavelets are efficient in reducing the number of parameters in the representation. Efficient representation of data facilitates processing of information contained in the data. The applications of wavelets include image, video and other data compression, denoising, and signal separation.
The multirate processing of two-dimensional (2D) signals involves various types of sampling and matrices, due to different grid geometry. A more consistent theory is then needed in order to obtain better techniques an...
详细信息
ISBN:
(纸本)081945351X
The multirate processing of two-dimensional (2D) signals involves various types of sampling and matrices, due to different grid geometry. A more consistent theory is then needed in order to obtain better techniques and useful results in many areas, such as image and signalprocessing, biomedical, telecommunications, multimedia, remote sensing, optics. In this work, a 2-channel complementary filter banks theory, designed based on 2D multirate processing and complementary filters properties is presented with foundations for multiresolution levels methods modeling, for the processing of signals in two-dimensions. in nonseparable way. signal analysis and synthesis using 2-channel complementary filter (CF) banks, the conditions under which the reconstruction of the 2D input signal is perfect and frequency division in the analysis part are developed. Since multiresolution decomposition of signals, wavelet representation and filter banks have a strong link, a relation of then with complementary filter banks is done. Other multiresolution levels methods can be derived from this theory and applications of them were found for compression, edge detection, 2D scaling and wavelets functions and digital TV systems.
With the aim of designing signalprocessing tools that act locally in space upon specific features of a signal, we compare two algorithms to remove or isolate individual anomalies in potential field profiles. The firs...
详细信息
With the aim of designing signalprocessing tools that act locally in space upon specific features of a signal, we compare two algorithms to remove or isolate individual anomalies in potential field profiles. The first method, based on multiscale edge analysis, leaves other features in the signal relatively untouched. A second method, based on iterative lateral continuation and subtraction of anomalies, accounts for the influence of adjacent anomalies on one another. This allows a potential field profile to be transformed into a number of single anomaly signals. Each single anomaly can then be individually processed, which considerably simplifies applications such as inversion and signalprocessing.
We propose a method based on second generation wavelets. After having tested the first generation wavelets hybridised with the latest video standard (the DCT has been replaced by the wavelets), we have shown that this...
详细信息
ISBN:
(纸本)0889864349
We propose a method based on second generation wavelets. After having tested the first generation wavelets hybridised with the latest video standard (the DCT has been replaced by the wavelets), we have shown that this transform is not adapted to our particular data. The new wavelet transform is performed using the powerful lifting scheme, keeping the main properties of the first generation wavelets whilst introducing some useful properties such as: analysis on general domains, suitable basis for weighted approximation / interpolation and weighted measure and transform adapted to irregular sampled data. With second generation wavelets, one can locate and encode the residual error of the motion compensation process, which mainly consists of high frequencies and singularities, typically the kind of data that second generation wavelet can successfully analyse.
High-resolutioin images are often desired but made impossible because of hardware limitations. For the high-resolution model proposed by Bose and Boo, the iterative wavelet-based algorithm has been shown to perform be...
详细信息
High-resolutioin images are often desired but made impossible because of hardware limitations. For the high-resolution model proposed by Bose and Boo, the iterative wavelet-based algorithm has been shown to perform better than the traditional least square method when the resolution ratio M is two and four. In this paper, we discuss the minimally supported biorthogonal wavelet system that comes from the mathematical model by Bose and Boo and propose a wavelet-based algorithm for arbitrary resolution ratio M greater than or equal to 2. The numerical results indicate that the algorithm based on our biorthogonal wavelet system performs better in high-resolution image reconstruction than the wavelet-based algorithm in the literature, as well as the common-used least square method.
Popular press and congressional record report a belief by the intelligence community that Al Qaeda members communicate through messages embedded invisibly in images shared via the Internet This is certainly plausible ...
详细信息
Popular press and congressional record report a belief by the intelligence community that Al Qaeda members communicate through messages embedded invisibly in images shared via the Internet This is certainly plausible as steganography has a rich history of military and civilian use. Current signature-based approaches for detecting the presence of hidden messages rely on discerning "footprints" of steganographic tools. Of greater recent concern is detecting the use of novel tools for which no signature has been established. This research addresses this concern by using a method for detecting anomalies in seemingly innocuous images, applying a genetic algorithm within a computational immune system to leverage powerful imageprocessing through wavelet analysis. The sensors developed with this system demonstrated a surprising level of capability to detect the use of steganographic tools for which the system had no previous exposure, including one tool designed to be statistically stealthy. (C) 2004 SPIE and IST.
In this paper an algorithm to measure large deformations using digital speckle pattern interferometry is presented. it facilitates recording of large number of frames and can subtract them to display speckle correlati...
详细信息
ISBN:
(纸本)0819454702
In this paper an algorithm to measure large deformations using digital speckle pattern interferometry is presented. it facilitates recording of large number of frames and can subtract them to display speckle correlation fringes with improved signal-to-noise ratio. To further improve signal-to-noise ratio a filtering scheme is also presented by using average/median filtering followed by wavelets filtering. Experimental results and analysis are presented in detail. For a typical displacement of 200 mum, error in measurement was less than 1.5 percent. Range in measurement is governed by change in scattering property of the surface of the object.
A formalism and an algorithm for configuring and sequencing parallel to massively parallel processors for the application of generalised spectral analysis transforms are presented. Successive partial rotations of a ba...
详细信息
A formalism and an algorithm for configuring and sequencing parallel to massively parallel processors for the application of generalised spectral analysis transforms are presented. Successive partial rotations of a base-p hypercube, where p is an arbitrary integer, are shown to produce dynamic contention-free memory allocation, in a generalised parallelism processor architecture. The approach is illustrated by factorisations involving the processing of matrices of transforms which are functions of four variables. Parallel operations are implemented as matrix multiplications. Each matrix, of dimension N x N, where N - p(n), n integer, has a structure that depends on a variable parameter k. The level of parallelism, in the form of M = p(m) processors, can be chosen arbitrarily by varying in between zero and its maximum value of n - 1. The result is an equation describing the generalised parallelism factorisation as a function of the four variables n, p, k and m. applications of the approach are shown in relation to complex matrix structures of imageprocessing generalised spectral analysis transforms. The same approach can be applied to a much larger class of parallel and multiprocessing systems for digital signalprocessingapplications.
Cellular Neural Networks (CNN) provides fast parallel computational capability for imageprocessingapplications. The behavior of the CNN is defined by two template matrices. In this paper, adjustment of these templat...
详细信息
ISBN:
(纸本)0819453625
Cellular Neural Networks (CNN) provides fast parallel computational capability for imageprocessingapplications. The behavior of the CNN is defined by two template matrices. In this paper, adjustment of these template-matrix coefficients have been realized using supervised learning algorithm based on back-propagation technique and wavelet function. Back-propagation algorithm has been modified for dynamic behavior of CNN. Wavelet function is utilized to provide the activation function derivation in this learning algorithm. The supervised learning algorithm is then executed to obtain a compact CNN architecture, called as Wave-CNN. The proposed new learning algorithm and Wave-CNN architecture performance have been tested for 2D imageprocessingapplications.
暂无评论