This paper addresses parallel execution of chain code generation on a linear array architecture. The contours in the proposed algorithm are viewed as a set of edges (or contour segments) that can be traced by a top-do...
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This paper addresses parallel execution of chain code generation on a linear array architecture. The contours in the proposed algorithm are viewed as a set of edges (or contour segments) that can be traced by a top-down contour tracing method to generate the chain codes for the outer and inner object contours. A parallel algorithm that contains the chain code generating rules and operations needed is also described, and the algorithm is mapped onto a one-dimensional systolic array containing [(1)/(2)(N + 1)] processing elements (PEs) to devise this architecture. The architecture extracts the contours of objects and quickly generates the corresponding chain codes after the image data in all rows are inputted in a linear fashion. The total processing time for generating the chain codes in an N x N image is O(3N). By doing so, the real-time requirement is fulfilled and its execution time is independent of the image content. In addition, a partition method is developed to process an image when the parallel architecture has a fixed number of PEs;say two or more. The total execution time for an N x N image by employing a fixed number of PEs is N(N + 1)/M + 2(M - 1), when M is the fixed number of PEs. (C) 2002 Elsevier Science Inc. All rights reserved.
We present an O((log log N)(2)) -time algorithm for computing the distance transform of an N x N binary image. Our algorithm is designed for the common concurrent read concurrent write parallel random access machine (...
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We present an O((log log N)(2)) -time algorithm for computing the distance transform of an N x N binary image. Our algorithm is designed for the common concurrent read concurrent write parallel random access machine (CRCW PRAM) and requires O(N2+epsilon / log log N) processors, for any epsilon such that 0 < E < 1. Our algorithm is based on a novel deterministic sampling scheme and can be used for computing distance transforms for a very general class of distance functions. We also present a scalable version of our algorithm when the number of processors is available p(2+epsilon) / log log p for some p < N. In this case, our algorithm runs in O((N-2/p(2)) + (N/p) log log p + (log log p)(2)) time. This scalable algorithm is more practical since usually the number of available processors is much less than the size of the image.
In this paper, we propose two novel parallel algorithms for identifying all the basis polygons in an image formed by n straight line segments each of which is represented by its two end points. The first algorithm is ...
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In this paper, we propose two novel parallel algorithms for identifying all the basis polygons in an image formed by n straight line segments each of which is represented by its two end points. The first algorithm is designed to tackle the simple situation where all basis polygons are convex. The second one deals with the general situation when the basis polygons can be both convex and non-convex. These algorithms are based on an idea of traversal along the periphery of the basis polygons in a well-defined manner so that each of these needs only 0(n) time using an n x n processor array. Simulation results on various test input sets of intersecting line segments have also been found satisfactory. (c) 2005 Elsevier B.V. All rights reserved.
We study parallel algorithms for certain classes of parabolic quasi-variational inequalities proposed by Lions in 1999, and examine the possibility of applying such algorithms to quasi variational inequalities that mo...
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We study parallel algorithms for certain classes of parabolic quasi-variational inequalities proposed by Lions in 1999, and examine the possibility of applying such algorithms to quasi variational inequalities that model type-II superconductors with critical current density depending on magnetic field in different situations.
This paper presents a self-organizing service modeling based on generalized particle dynamics (GPD) for distributed service systems.(dagger) Differing from traditional service models, the GPD-based self-organizing ser...
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ISBN:
(纸本)1424404509
This paper presents a self-organizing service modeling based on generalized particle dynamics (GPD) for distributed service systems.(dagger) Differing from traditional service models, the GPD-based self-organizing service modeling may provide optimal services according to user requirements. The GPD conception, algorithm and its properties are discussed. The GPD-based self-organizing service modeling has advantages in terms of the real-time performance, adaptability, reliability and the learning ability over traditional service models.
This paper presents a parallel Linear Hashtable Motion Estimation algorithm (LHMEA). Most parallel video compression algorithms focus on Group of Picture (GOP). Based on LHMEA we proposed earlier [1][2], we developed ...
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ISBN:
(数字)9783540377849
ISBN:
(纸本)3540377832
This paper presents a parallel Linear Hashtable Motion Estimation algorithm (LHMEA). Most parallel video compression algorithms focus on Group of Picture (GOP). Based on LHMEA we proposed earlier [1][2], we developed a parallel motion estimation algorithm focus inside of frame. We divide each reference frames into equally sized regions. These regions are going to be processed in parallel to increase the encoding speed significantly. The theory and practice speed up of parallel LHMEA according to the number of PCs in the cluster are compared and discussed. Motion Vectors (MV) are generated from the first-pass LHMEA and used as predictors for second-pass Hexagonal Search (HEXBS) motion estimation, which only searches a small number of Macroblocks (MBs). We evaluated distributed parallel implementation of LHMEA of TPA for real time video compression.
This paper propose a maze routing algorithm based on cellular automata. The aim of this algorithm is find the shortest path between the source cell and the target cell, so that the path does not pass from the obstacle...
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ISBN:
(纸本)3540409297
This paper propose a maze routing algorithm based on cellular automata. The aim of this algorithm is find the shortest path between the source cell and the target cell, so that the path does not pass from the obstacles. algorithm has two phases, exploration and retrace. In exploration phase a wave is expanded from source cell and it puts token on cells which it passes via them while expanding. In the retracing phase, we start from target cell, follow the wave and arrive to source cell;the path created in this phase is desirable. Propose algorithm is simple and it's transactions are local and follow the cellular automata properties. This algorithm find the desirable path in m x m two dimensional CA in O(m(2)) time step.
Inverse (time-reverse) simulation of three-dimensional thermoconvective flows is considered for a highly viscous incompressible fluid with temperature-dependent density and viscosity. The model of the fluid dynamics i...
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The knapsack problem is very important in cryptosystem and in number theory. This paper proposes a new parallel algorithm for the knapsack problem where the method of divide and conquer is adopted. Basing on an EREW-S...
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ISBN:
(纸本)0780378407
The knapsack problem is very important in cryptosystem and in number theory. This paper proposes a new parallel algorithm for the knapsack problem where the method of divide and conquer is adopted. Basing on an EREW-SIMD machine with shared memory, the proposed algorithm utilizes O(2(n/4))(1-epsilon) processors, 0less than or equal to epsilon less than or equal to 1, and O(2(n)) memory to find a solution for the n-element knapsack problem in time O(2(n/4) (2(n/4))epsilon). Thus the cost of the proposed parallel algorithm is O(2(n)), which is optimal, and an improved result over the past researches. Keywords: Knapsack problem, parallel algorithm, optimal algorithm, memory conflicts.
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