This study presents a class of four-channel multiplierless reversible Hadamard transforms (HTs), called lifting-Householder-based HT (LiftH(2)T), for various signalprocessing and communication applications. This clas...
详细信息
ISBN:
(纸本)9781479983391
This study presents a class of four-channel multiplierless reversible Hadamard transforms (HTs), called lifting-Householder-based HT (LiftH(2)T), for various signalprocessing and communication applications. This class is obtained by using a lifting-Householder factorization of a particular 4 x 4 symmetric orthogonal matrix and its application to a four-channel HT. In spite of the simple multiplierless structure with only nine adders, one shifter, and three process steps, it basically outperforms the integer HT (IntHT) and lifting-based HT (LiftHT) in the JPEG xR standard at lossy-to-lossless image coding, thanks to its considering the dynamic range and having less rounding error.
in this paper, we develop a new semi-automated segmentation method to cancel the chaotic blood flow signal within the left ventricle (LV) in cardiac magnetic resonance (MR) images with parallel imaging. The segmentati...
详细信息
ISBN:
(纸本)9781479986378
in this paper, we develop a new semi-automated segmentation method to cancel the chaotic blood flow signal within the left ventricle (LV) in cardiac magnetic resonance (MR) images with parallel imaging. The segmentation is performed using a deformable model driven by a new external energy based on estimated probability density function (pdf) of the MR signal in the LV. The use of noise distribution through the data allows us both to pull the contour towards the myocardium edges and to ensure the smoothness of the curve. Since data for each slice are acquired with the GRAPPA parallel imaging technique, the spatial segmentation is followed by a temporal propagation to improve the convergence in terms of quality and rapidity. Experiments demonstrate that the proposed model provides better results than those obtained from the standard Active Contour, which should facilitate the use of the method for clinical purposes.
Data fusion can be used to generate high quality data from multiple, degraded data sets by appropriately extracting and combining "good" information from each degraded set. In particular for image fusion, it...
详细信息
ISBN:
(纸本)9781628416138
Data fusion can be used to generate high quality data from multiple, degraded data sets by appropriately extracting and combining "good" information from each degraded set. In particular for image fusion, it may be used for image denoising, deblurring, or pixel dropout compensation. image fusion is often performed in an image transform domain. In transform domain fusion approaches, transform coefficients from multiple images may be combined in various ways to produce an improved transform coefficient set. The fused transform data is inverted to produce the fused image. In this paper we formulate a general approach to image fusion in the wavelet domain. The proposed approach exploits context information, through application of nonparametric statistical hypothesis testing. The use of statistical hypothesis testing places the fusion on a theoretically sound and principled basis, and leads to improved fusion performance. Furthermore, use of statistical wavelet coefficient information in a neighborhood of the test coefficient more fully exploits the available context information. In this paper we first formulate the fusion approach. We then present numerical image data fusion results using a sampling of imagery from a public domain image database. We compare fusion performance of the proposed approach with performance of other standard wavelet-domain fusion approaches, and show a performance improvement when using the proposed approach.
This paper proposes an efficient VLSI architecture for discrete Hadamard transform, which is used in real time digital signalprocessingapplications like image coding, MPEG, and CDMA etc. The proposed N-point Hadamar...
详细信息
This paper proposes an efficient VLSI architecture for discrete Hadamard transform, which is used in real time digital signalprocessingapplications like image coding, MPEG, and CDMA etc. The proposed N-point Hadamard transform architecture consists of signed carry save adder tree. So the depth of the architecture falls within the bounds of O (log2 N). The same proposed architecture is implemented for 2D-discrete Hadamard transform, where the hardware utilization is full. In other words, row/column processing of 2D-transform is carried with same 1D-hardware. The performance results show that the proposed architecture gives better performance compared with existing architectures using 45 nm CMOS TSMC library. The proposed 8-point 1D-DHT achieves an improvement of 55.14% and 42.07% in worst path delay over conventional and linear systolic array based 1D-DHT architectures respectively. Similarly proposed 8x8-point 2D-DHT achieves an improvement of 50.7%, 21.7%, and 51.1% in worst path delay over conventional, linear systolic array, and distributed arithmetic based 2D-DHT architectures respectively.
In this paper, we give a new definition of fuzzy contours in mammographic images and we propose an approach to get them. This approach starts from region of interest images with initial contours delimiting masses prov...
详细信息
ISBN:
(纸本)9781479986378
In this paper, we give a new definition of fuzzy contours in mammographic images and we propose an approach to get them. This approach starts from region of interest images with initial contours delimiting masses provided by an expert radiologist, and then it involves three major stages: mass segmentation using geometric deformable models, contour representation and finally definition of fuzzy contours. For the first phase, the initial zero level set is performed by using the initial contour guided by the radiologist. After that, we propose a new representation of contours. Since the segmentation of masses in mammograms is a difficult problem due to the characteristics of mammographic image, and even mass edges can be identified differently by different radiologists and also by the same radiologist at a different time, we define an entire region that may contain the accurate edges, in which we assign to each pixel a membership value to the class "Contour". We call that fuzzy contours.
The use of multisensors images for different applications, like change detection and image fusion, require an image to image ***, the image registration becomes a crucial task with the continuous increase in image res...
详细信息
The use of multisensors images for different applications, like change detection and image fusion, require an image to image ***, the image registration becomes a crucial task with the continuous increase in image resolution, especially in urban *** this paper, a refined automatic Mutual Information based registration approach of spaceborne Synthetic Aperture radar(SAR) and optical image is *** data set include Terra Sar-x(1m) and Worldview-2(0.5m) images and cover urban area of San *** approach is divided into two ***, we use Discrete Canny edge detector to extract contours from the optical image, and Gabor-Wavelet filter to extract edge from the SAR ***, a rigid transformation(rotation and translation) is applied to the contours image obtained by Canny ***, for each value of transformation, the Mutual Information is computed between this transformed image and the feature image outcome of application of Gaborwavelet to the SAR *** best transformation parameters are obtained when the Mutual Information is ***, in this work, we compared the proposed approach with the basic Mutual Information intensity based registration *** results obtained demonstrated that our approach improve the registration accuracy comparatively to the basic Mutual Information intensity based registration method.
This work deals with denosing of a one-dimensional signal corrupted by additive white Gaussian noise. A common way to solve the problem is to utilize the total variation (TV) method. Basically, the TV regularization m...
详细信息
ISBN:
(纸本)9781628417654
This work deals with denosing of a one-dimensional signal corrupted by additive white Gaussian noise. A common way to solve the problem is to utilize the total variation (TV) method. Basically, the TV regularization minimizes a functional consisting of the sum of fidelity and regularization terms. We derive explicit solutions of the one-dimensional TV regularization problem that help us to restore noisy signals with a direct, non-iterative algorithm. Computer simulation results are provided to illustrate the performance of the proposed algorithm for restoration of noisy signals.
Halftoning and inverse halftoning algorithms are very important imageprocessing tools that have been widely used in digital printers, scanners, steganography and image authentication systems. Because such application...
详细信息
ISBN:
(纸本)9781479984985
Halftoning and inverse halftoning algorithms are very important imageprocessing tools that have been widely used in digital printers, scanners, steganography and image authentication systems. Because such applications require obtaining high quality gray scale images from its halftoning versions, several inverse halftoning algorithms have been proposed during the last several years, which provide gray scale images with Peak signal to Noise Ratio (PSNR) of about 25 to 28 dB. Although this may be enough for several applications, exist several other that require higher image quality. To this end, this paper proposes an inverse halftoning algorithm based on Upx atomic function and multilayer perceptron neural network. Experimental results show that proposed scheme provides gray scale images with PSNRs higher than 30dB independently of the method used to generate the halftone image.
The continuous linear canonical transforms (LCT) can describe a wide variety of wave field propagations through paraxial (first order) optical systems. Digital algorithms to numerically calculate the LCT are therefore...
详细信息
ISBN:
(纸本)9781628417654
The continuous linear canonical transforms (LCT) can describe a wide variety of wave field propagations through paraxial (first order) optical systems. Digital algorithms to numerically calculate the LCT are therefore important in modelling scalar wave field propagations and are also of interest for many digital signalprocessingapplications. The continuous LCT is additive, but discretization can remove this property. In this paper we discuss three special cases of the LCT for which constraints can be identified to ensure the DLCT is additive.
Transform skip modes (TSM) have previously been proposed for HEVC, where a transform on the prediction residual is skipped in one or both directions. TSM can improve coding efficiency when the prediction errors have m...
详细信息
ISBN:
(纸本)9781479986378
Transform skip modes (TSM) have previously been proposed for HEVC, where a transform on the prediction residual is skipped in one or both directions. TSM can improve coding efficiency when the prediction errors have minimal correlation in one or both directions. In this paper, improvements are proposed to the 1D transform skip mode design. Specifically, a unified dynamic range control method is proposed for the horizontalonly and vertical-only 1D TSM. It is also proposed to modify the scan order of the transform coefficients and to apply coefficient flipping to some 1D TSM cases. Finally, a number of efficient encoder complexity reduction methods are considered for the proposed 1D TSM. Experimental results show that the proposed method can achieve up to 4.7% gain in coding efficiency with limited encoder complexity increase. The proposed method also significantly improves visual quality, especially in areas rich in text and graphics.
暂无评论