The discrete wavelet transform (DWT) has been touted as avery effective tool in many signalprocessingapplications, including compression, denoising and modulation. For example, the forthcoming JPEG 2000 image compre...
详细信息
ISBN:
(纸本)0819432997
The discrete wavelet transform (DWT) has been touted as avery effective tool in many signalprocessingapplications, including compression, denoising and modulation. For example, the forthcoming JPEG 2000 image compression standard will be based on the DWT. However, in order for the DWT to achieve the popularity of other more established techniques (e.g., the DCT in compression) a substantial effort is necessary in order to solve some of the related implementation issues. Specific issues of interest include memory utilization, computation complexity and scalability. In this paper we concentrate an wavelet-based image compression and provide examples, based on our recent work, of how these implementation issues can be addressed in three different environments, namely, memory constrained applications, software-only encoding/decoding,and parallel computing engines. Specifically we will discuss (i) a low memory image coding algorithm that employs aline-based transform, (ii) a technique to exploit the sparseness of non-zero wavelet coefficients in a software-only image decoder, and (iii) parallel implementation techniques that take full. advantage of lifting filterbank factorizations.
We discuss a method for initializing the multi-wavelet decomposition algorithm by pre-filtering. The proposed pre-filtering operation projects the input signal into the space defined by the multi-scaling function asso...
详细信息
ISBN:
(纸本)0819425915
We discuss a method for initializing the multi-wavelet decomposition algorithm by pre-filtering. The proposed pre-filtering operation projects the input signal into the space defined by the multi-scaling function associated with the multi-wavelet. Since the approach is projection based, it is guaranteed to always have a solution. The space in which the original signal is contained is defined by multiple generating functions, making this work a generalization of our previous results.
A novel method for the automatic generation of a facial texture is proposed in this paper. Multiple pictures from the individual are combined to create the texture using a wavelet-based technique. The different tasks ...
详细信息
ISBN:
(纸本)9781424404810
A novel method for the automatic generation of a facial texture is proposed in this paper. Multiple pictures from the individual are combined to create the texture using a wavelet-based technique. The different tasks involved in the proposed method include: scaling, histogram equalization, deformation and merging. A set of particular feature points of the MPEG-4 standard for multimedia applications is used in the above mentioned tasks. In the merging stage, wavelet multiresolution decomposition of the images and filtering of the wavelet coefficients are performed to obtain a seamless texture. Finally, the resulting texture is mapped onto a 3D head model which has been adapted to the particular individual based on the same pictures. Since the proposed method relies on the MPEG-4 Facial and Body Animation (FBA) standard, it can be easily integrated with applications using the same standard.
In this work, a new image watermarking algorithm on colour images is proposed. The proposed algorithm divides a cover image into three colour bands of red, green and blue. Then the following tasks are done on all thre...
详细信息
ISBN:
(纸本)9781509064946
In this work, a new image watermarking algorithm on colour images is proposed. The proposed algorithm divides a cover image into three colour bands of red, green and blue. Then the following tasks are done on all three channels separately. First, Each colour band is divided into patches of small sizes then the entropy of each patch is calculated. At this step a threshold is found based on the average entropy of all patches and following is applied to all patches which have entropy lower than the threshold. A wavelet representation of each patch are given by applying a discrete wavelet transform. Then Singular value decomposition, orthogonal-triangular decomposition, and a chirp z-transform are used to embed a watermark on the cover image. Several signalprocessing attacks are applied on watermarked images in order to robustness of the algorithm. The Proposed algorithm is compared with one conventional and two state-of-the-art algorithms. Experimental results show superiority of the proposed algorithm compare with other algorithm in the area of image watermarking.
The diagnosis of Alzheimer's disease (AD) at the present time remains dependent upon clinical symptomatology. Lifetime accuracy in the best clinics remains 86-89%, and mean diagnostic delay in the clinical course ...
详细信息
ISBN:
(纸本)0819437646
The diagnosis of Alzheimer's disease (AD) at the present time remains dependent upon clinical symptomatology. Lifetime accuracy in the best clinics remains 86-89%, and mean diagnostic delay in the clinical course of the disease remains 3.6 years after symptomatic onset. Although EEG is an obvious quantitative parameter related to the illness, it's limitation is the absence of an identified set of features that discriminates AD EEG abnormalities from those due to confounding conditions. As a consequence, no computerized method exists up to date that can reliably detect those abnormalities. The objective of this study is to develop a robust computerized method for early detection of AD in EEG. We explore the ability of specifically designed and trained recurrent neural networks (RNN), combined with wavelet preprocessing, to discriminate between EEGs of early onset AD patients and their age-matched control subjects. We have used a similar approach previously for predicting the onset of epileptic seizure in EEG [1,2]. The RNNs are chosen because they can implement extremely nonlinear decision boundaries and possess memory of the state, which is crucial for the considered task. The results on eyes-closed resting EEG reveal particularly favorable network behavior when applied to wavelet-filtered subbands as opposed to original signal data.
A scheme for extracting morphological information from images through a edge oriented wavelet decomposition is proposed. Multiresolution edge patterns extracted in the wavelet transform domain are represented by param...
详细信息
ISBN:
(纸本)0819432997
A scheme for extracting morphological information from images through a edge oriented wavelet decomposition is proposed. Multiresolution edge patterns extracted in the wavelet transform domain are represented by parameterized segments. Tracking these segments across consecutive frames of a sequence leads to a parametric cynematic echaracterization of the content of a video sequence, suited for high level syntactic processing.. Parameterized images are visualizable by means of the inverse wavelet transform.
The wavelet transform technology is widely used in many fields, such as the graphics processing, the imageprocessing, the video-voice processing, and the digital signalprocessing, and has achieved good application r...
详细信息
ISBN:
(纸本)9783030152352;9783030152345
The wavelet transform technology is widely used in many fields, such as the graphics processing, the imageprocessing, the video-voice processing, and the digital signalprocessing, and has achieved good application results. Starting from the principles and types of the imageprocessing technology based on the wavelet transform, two processing methods of the continuous wavelet transform and the discrete wavelet transform are described in detail, and their specific applications and advantages in the image compression and the image denoising are enumerated.
alpha stable distribution and its fractional lower order statistics (FLOS) are introduced in this paper. Meanwhile the non-Gauss characteristics of some signals are considered in the practical applications. The method...
详细信息
ISBN:
(纸本)1424411351
alpha stable distribution and its fractional lower order statistics (FLOS) are introduced in this paper. Meanwhile the non-Gauss characteristics of some signals are considered in the practical applications. The method based on FLOS is the important method of signal analysis and processing under the signal and/or noise condition of non-Gauss alpha stable distribution. The medicine images are taken as the example. The FLOS in company with wavelet transform is introduced, and two parameters of wavelet coefficients for the images: alpha and gamma are estimated. It is explained that when in the practical imageprocessing, we must consider the non-Gauss characteristics of signal to avoid performance degeneration with conventional signalprocessing methods. The proposed algorithm builds the foundation for the following imageprocessing such as using Bayes wavelet to remove the noise and so on.
A multiscale vision model based on a pyramidal wavelet transform is described in the present paper. The pyramidal wavelet algorithm is modified in order to satisfy a correct sampling at each scale. Objects are defined...
详细信息
wavelet based compression schemes belong to the general class of transform coding schemes. We show how the genetic programming approach can be used to optimize such a compression scheme in the sense of rate-distortion...
详细信息
ISBN:
(纸本)0819419281
wavelet based compression schemes belong to the general class of transform coding schemes. We show how the genetic programming approach can be used to optimize such a compression scheme in the sense of rate-distortion. The results of optimized wavelet based compression scheme are compared with the JPEG compression standard. A prototype implementation of the method is realized as a distributed, parallel implementation on a heterogeneous Unix network.
暂无评论