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[Keyword] meshes(9hit)

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  • Compression of Dynamic 3D Meshes and Progressive Displaying

    Bin-Shyan JONG  Chi-Kang KAO  Juin-Ling TSENG  Tsong-Wuu LIN  

     
    PAPER-Computer Graphics

      Vol:
    E94-D No:11
      Page(s):
    2271-2279

    This paper introduces a new dynamic 3D mesh representation that provides 3D animation support of progressive display and drastically reduces the amount of storage space required for 3D animation. The primary purpose of progressive display is to allow viewers to get animation as quickly as possible, rather than having to wait until all data has been downloaded. In other words, this method allows for the simultaneous transmission and playing of 3D animation. Experiments show that coarser 3D animation could be reconstructed with as little as 150 KB of data transferred. Using the sustained transmission of refined operators, viewers feel that resolution approaches that of the original animation. The methods used in this study are based on a compression technique commonly used in 3D animation - clustered principle component analysis, using the linearly independent rules of principle components, so that animation can be stored using smaller amounts of data. This method can be coupled with streaming technology to reconstruct animation through iterative updating. Each principle component is a portion of the streaming data to be stored and transmitted after compression, as well as a refined operator during the animation update process. This paper considers errors and rate-distortion optimization, and introduces weighted progressive transmitting (WPT), using refined sequences from optimized principle components, so that each refinement yields an increase in quality. In other words, with identical data size, this method allows each principle component to reduce allowable error and provide the highest quality 3D animation.

  • An Efficient Method for Converting Polygonal Models into Displaced Subdivision Representation

    Muhammad HUSSAIN  Yoshihiro OKADA  Koichi NIIJIMA  

     
    PAPER-Computer Graphics

      Vol:
    E89-A No:3
      Page(s):
    807-816

    Displaced subdivision surface representation [13] is a new form of representing a polygonal surface model, where a detailed surface model is defined as a scaler-valued displacement map over a smooth domain surface; it puts forth a number of attractive features for editing, geometry compression, animation, scalability, and adaptive rendering of polygonal models. The construction of the smooth domain surface is a challenging task in the conversion process of a detailed polygonal surface model into this representation. In this paper, we propose a new efficient method for defining the smooth domain surface based on -subdivision scheme. The proposed algorithm not only performs better in terms of the quality of the generated surfaces but is computationally more efficient and occupies less memory as compared to the original algorithm [13] and generates surfaces with more levels of detail due to the specific nature of -subdivision when the prescribed target complexity of the generated mesh must not be exceeded. To corroborate the efficiency and the quality of the new technique, the conversion results for several public domain models have been presented.

  • Measuring Errors on 3D Meshes Using Pixel Based Search

    Kohji INAGAKI  Masahiro OKUDA  Masaaki IKEHARA  Shin-ichi TAKAHASHI  

     
    PAPER-Computer Graphics

      Vol:
    E86-D No:9
      Page(s):
    1903-1908

    Due to the explosive growth of the network technologies, 3D models and animations have led to a great interest in various media. Especially 3D mesh models (3D meshes), which approximate surfaces by polygonal meshes are widely used to model 3D objects. In 1D and 2D signals such as speech, audio, images, video, etc., the signal values are located on "grids", for example the signals of images are defined on pixels. Thus, the errors of such signals can be explicitly defined by differences of the values on the "grids". However since in the 3D meshes, vertices are located on arbitrary positions in a 3D space and are triangulated in arbitrary ways, the grids cannot be defined. This makes it difficult to measure error on the 3D meshes. In this paper, we propose a new numerical method to measure the errors between two different 3D meshes.

  • Dynamic Scheduling and Allocation in Two-Dimensional Mesh-Connected Multicomputers for Real-Time Tasks

    Seong-Moo YOO  Hee Yong YOUN  Hyunseung CHOO  

     
    PAPER-Computer Systems

      Vol:
    E84-D No:5
      Page(s):
    613-622

    Among several multiprocessor topologies, two-dimensional (2D) mesh topology has become popular due to its simplicity and efficiency. Even though a number of scheduling and processor allocation schemes for 2D meshes have been proposed in the literature, little study has been done aimed for real-time environment. In this paper, we propose an on-line scheduling and allocation scheme for real-time tasks that require the exclusive use of submeshes in 2D mesh system. By effectively manipulating the information on allocated or reserved submeshes, the proposed scheme can quickly identify the earliest available time of a free submesh for a newly arrived task. We employ a limited preemption approach to reduce the complexity of the search for a feasible schedule. Computer simulation reveals that the proposed scheme allows high throughput by decreasing the number of tasks rejected.

  • Recent Developments in Mesh Routing Algorithms

    Kazuo IWAMA  Eiji MIYANO  

     
    INVITED SURVEY PAPER-Parallel and Distributed Algorithms

      Vol:
    E83-D No:3
      Page(s):
    530-540

    The two dimensional mesh is widely considered to be a promising parallel architecture in its scalability. In this architecture, processors are naturally placed at intersections of horizontal and vertical grids, while there can be three different types of communication links: (i) The first type is the most popular model, called a mesh-connected computer: Each processor is connected to its four neighbours by local connections. (ii) Each processor of the second type is connected to a couple of (row and column) buses. The system is then called a mesh of buses. (iii) The third model is equipped with both buses and local connections, which is called a mesh-connected computer with buses. Mesh routing has received considerable attention for the last two decades, and a variety of algorithms have been proposed. This paper provides an overview of lower and upper bounds for algorithms, with pointers to the literature, and suggests further research directions for mesh routing.

  • Fault-Tolerant Meshes with Efficient Layouts

    Toshinori YAMADA  Shuichi UENO  

     
    PAPER-Fault Tolerant Computing

      Vol:
    E81-D No:1
      Page(s):
    56-65

    This paper presents a practical fault-tolerant architecture for mesh parallel machines that has t spare processors and has 2(t+2) communication links per processor while tolerating at most t+1 processor and link faults. We also show that the architecture presented here can be laid out efficiently in a linear area with wire length at most O(t).

  • TESH: A New Hierarchical Interconnection Network for Massively Parallel Computing

    Vijay K. JAIN  Tadasse GHIRMAI  Susumu HORIGUCHI  

     
    PAPER-Interconnection Networks

      Vol:
    E80-D No:9
      Page(s):
    837-846

    Advanced scientific and engineering problems require massively parallel computing. Critical to the designand ultimately the performanceof such computing systems is the interconnection network binding the computing elements, just as is the cardiovascular network to the human body. This paper develops a new interconnection network, "Tori connected mESHes (TESH)," consisting of k-ary n-cube connection of supernodes that comprise meshes of lower level nodes. Its key features are the following: it is hierarchical, thus allowing exploitation of computation locality as well as easy expansion (up to a million processors), and it appears to be well suited for 3-D VLSI implementation, for it requires far fewer number of vertical wires than almost all known multi-computer networks. Presented in the paper are the architecture of the new network, node addressing and message routing, 3-D VLSI/ULSI considerations, and application of the network to massively parallel computing. Specifically, we discuss the mapping on to the network of stack filtering, a hardware oriented technique for order statistic image filtering.

  • Analysis of the Shielding Properties of Planar Wire-Mesh Shields, Loaded by General Stratified Structures

    Riccardo E. ZICH  

     
    PAPER

      Vol:
    E78-B No:2
      Page(s):
    238-245

    The analysis of the shielding properties of a planar wire-mesh shield embedded in a general isotropic--chirality is included--or anisotropic stratified media is here presented. A suitable model of the grating has been introduced in order to consider the occuring phenomena, in fact through a spectral technique the electromagnetic problem is translated into the equivalent circuit network model that allows to express the time response of the shielded field for the NEMP incidence in a closed form.

  • Surface Reconstruction Model for Realistic Visualization

    Hiromi T. TANAKA  Fumio KISHINO  

     
    PAPER

      Vol:
    E76-D No:4
      Page(s):
    494-500

    Surface reconstruction and visualization from sparse and incomplete surface data is a fundamental problem and has received growing attention in both computer vision and graphics. This paper presents a computational scheme for realistic visualization of free-formed surfaces from 3D range images. The novelty of this scheme is that by integrating computer vision and computer graphics techniques, we dynamically construct a mesh representation of the arbitrary view of the surfaces, from a view-invariant shape description obtained from 3D range images. We outline the principle of this scheme and describle the frame work of a graphical reconstruction model, we call arbitrarily oriented meshes', which is developed based on differential geometry. The experimental results on real range data of human faces are shown.