The fractional wavelet transform (FRWT), which generalizes the classical wavelet transform, has been shown to be potentially useful for signalprocessing. Many fundamental results of this transform are already known, ...
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The fractional wavelet transform (FRWT), which generalizes the classical wavelet transform, has been shown to be potentially useful for signalprocessing. Many fundamental results of this transform are already known, but the theory of multiresolution analysis and orthogonal wavelets is still missing. In this paper, we first develop multiresolution analysis associated with the FRWT and then derive a construction of orthogonal wavelets for the FRWT. Several fractional wavelets are also presented. Moreover, some applications of the derived results are discussed.
A new memory data scheduling scheme is used for designing a two-dimensional discrete wavelet transform (2D-DWT) core for ASIC implementation. This scheme reduces by 20 to 30% the overall switching activity in the 2D-D...
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A new memory data scheduling scheme is used for designing a two-dimensional discrete wavelet transform (2D-DWT) core for ASIC implementation. This scheme reduces by 20 to 30% the overall switching activity in the 2D-DWT core and hence leads to lower power consumption at the expense of a slight reduction in the quality of reconstructed images and a slight increase in the chip area. This scheme is particularly useful in applications such as wireless Internet and laptop computers, in which picture quality can be traded-off for reduced power consumption.
B-splines caught interest of many engineering applications due to their merits of being flexible and provide a large degree of differentiability and cost/quality trade-off relationship. However, they have less impact ...
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B-splines caught interest of many engineering applications due to their merits of being flexible and provide a large degree of differentiability and cost/quality trade-off relationship. However, they have less impact with continuous-time applications as they are constructed from piecewise polynomials. On the other hand, exponential spline polynomials (E-splines) represent the best smooth transition between continuous and discrete domains as they are made of exponential segments. In this paper, we present a complete analysis for an E-spline-based subband coding (wavelet) perfect reconstruction (PR) system. Derivations for the scaling and wavelet functions are presented, along with application of the proposed system in image compression and image denoising. In image compression, a comparison of the proposed technique compared with the B-spline-based PR system as well as the basic wavelet subband system with the SPIHT image codec is presented. In image denoising, we report the enhancement achieved with the proposed E-spline-based denoising approach compared with B-spline-based denoising and another basic denoising technique. In both applications, E-splines show superior performance as will be illustrated.
This paper develops new algorithms for adapted multiscale analysis and signal adaptive wavelet transforms. We construct our adaptive transforms with the lifting scheme, which decomposes the wavelet transform into pred...
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ISBN:
(纸本)0819432997
This paper develops new algorithms for adapted multiscale analysis and signal adaptive wavelet transforms. We construct our adaptive transforms with the lifting scheme, which decomposes the wavelet transform into prediction and update stages. We adapt the prediction stage to the signal structure and design the update stage to preserve the desirable properties of the wavelet transform. The resulting scale and spatially adaptive transforms are extended to the image estimation problem;our new image transforms show improved denoising performance over existing (non-adaptive) orthogonal transforms.
The lifting scheme is well known to be an efficient tool for constructing second generation wavelets and is often used to design a class of biorthogonal wavelet filter banks. For its efficiency, the lifting implementa...
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The lifting scheme is well known to be an efficient tool for constructing second generation wavelets and is often used to design a class of biorthogonal wavelet filter banks. For its efficiency, the lifting implementation has been adopted in the international standard JPEG2000. It is known that the orthogonality of wavelets is an important property for many applications. This paper presents how to implement a class of infinite-impulse-response (IIR) orthogonal wavelet filter banks by using the lifting scheme with two lifting steps. It is shown that a class of IIR orthogonal wavelet filter banks can be realized by using allpass filters in the lifting steps. Then, the design of the proposed IIR orthogonal wavelet filter banks is discussed. The designed IIR orthogonal wavelet filter banks have approximately linear phase responses. Finally, the proposed IIR orthogonal wavelet filter banks are applied to the image compression, and then the coding performance of the proposed IIR filter banks is evaluated and compared with the conventional wavelet transforms.
In this paper, based on the logarithmic imageprocessing model and the dyadic wavelet transform (DWT), we introduce a logarithmic DWT (LDWT) that is a mathematical transform. It can be used in image edge detection, si...
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In this paper, based on the logarithmic imageprocessing model and the dyadic wavelet transform (DWT), we introduce a logarithmic DWT (LDWT) that is a mathematical transform. It can be used in image edge detection, signal and image reconstruction. Comparative study of this proposed LDWT-based method is done with the edge detection Canny and Sobel methods using Pratt's Figure of Merit, and the comparative results show that the LDWT-based method is better and more robust in detecting low contrast edges than the other two methods. The gradient maps of images are detected by using the DWT- and LDWT-based methods, and the experimental results demonstrate that the gradient maps obtained by the LDWT-based method are more adequate and precisely located. Finally, we use the DWT- and LDWT-based methods to reconstruct one-dimensional signals and two-dimensional images, and the reconstruction results show that the LDWT-based reconstruction method is more effective. (C) 2014 Elsevier B.V. All rights reserved.
An efficient high precision biorthogonal 9/7 wavelet filter structure for imageprocessingapplications was proposed. This structure aimed at high precision applications. A precision improved distributed algorithms (D...
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An efficient high precision biorthogonal 9/7 wavelet filter structure for imageprocessingapplications was proposed. This structure aimed at high precision applications. A precision improved distributed algorithms (DA) had been proposed. Comparing with traditional DA implementations, the new DA had higher precision while preserves smaller area. The proposed structure was verified in Spartan-6 field programmable gate array (FPGA) and achieved 200 MHz operation frequency. The peak signal to noise ratio (PSNR) of reconstructed image (Lena) achieves 74 dB which is very high comparing with other implementations.
This paper describes a dynamic partial reconfiguration (DPR) design flow and environment for image and signalprocessing algorithms used in adaptive applications. Based on the evaluation of the existing DPR design flo...
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This paper describes a dynamic partial reconfiguration (DPR) design flow and environment for image and signalprocessing algorithms used in adaptive applications. Based on the evaluation of the existing DPR design flow, important features such as overall flexibility, application and standardised interfaces, host applications and DPR area/size placement have been taken into consideration in the proposed design flow and environment. Three intellectual property (IP) cores used in pre-processing and transform blocks of compression systems including colour space conversion (CSC), two-dimensional biorthogonal discrete wavelet transform (2-D DBWT) and three-dimensional Haar wavelet transform (3-D HWT) have been selected to validate the proposed DPR design flow and environment. Results obtained reveal that the proposed environment has a better solution providing: a scriptable program to establish the communication between the field programmable gate array (FPGA) with IP cores and their host application, power consumption estimation for partial reconfiguration area and automatic generation of the partial and initial bitstreams. The design exploration offered by the proposed DPR environment allows the generation of efficient IP cores with optimised area/speed ratios. Analysis of the bitstream size and dynamic power consumption for both static and reconfigurable areas is also presented in this paper. (C) 2010 Elsevier B.V. All rights reserved.
Fusion image is the method of extracting the relevant information from two or more identical input images into one scene and creating a new image. This method allows the new image to provide comprehensive information ...
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Fusion image is the method of extracting the relevant information from two or more identical input images into one scene and creating a new image. This method allows the new image to provide comprehensive information about the wand, leading to a visual understanding of the human being. Fusion image application in imageprocessing is an important issue. applications in many fields such as photography, microscopy, astronomy, medical imaging, satellite imagery, machine vision, biology are monitored. In this study first, an image fusion method, suggested recently based on transform empirical wavelet, was implemented in which coefficients were obtained by processing the input images. Then they were combined by applying the rules. The aim of this study is to investigate the noise effect and to remove the noise in the aforementioned suggested method. First, the noise was added to the images, and the images were decomposed into layers or coefficients. Second, by thresholding the coefficients, the noise was removed. Then the coefficients were combined based on the rules to obtain the final coefficients. In the end, the final coefficients were used to obtain the fused image. The results show that the noise removal of images during image fusion is much better and more effective than denoising before image fusion, and the demonstration of the method is proved by obtaining better results in comparison to some existing methods.
A wavelet-based image gradient transform is proposed. The proposed transform, called multi-scale gradient transform (MSGT), obtains the first order derivative of an image in terms of the wavelet detail coefficients. W...
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ISBN:
(纸本)9781467345729
A wavelet-based image gradient transform is proposed. The proposed transform, called multi-scale gradient transform (MSGT), obtains the first order derivative of an image in terms of the wavelet detail coefficients. While traditional methods estimate the image gradients at each wavelet scale in terms of the horizontal and vertical wavelet coefficients only, the proposed transform obtains the gradients in terms of the diagonal, as well as the horizontal and vertical wavelet coefficients. The proposed MSGT is designed to be invertible, non-redundant and computationally efficient. We demonstrate the potential applications of the proposed transform in texture feature extraction, multi-scale edge detection, image quality assessment and image watermarking.
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