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Universal Data Compression by Digram

Research Project

Project/Area Number 09650404
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field 情報通信工学
Research InstitutionTHE UNIVERSITY OF ELECTRO-COMMUNICATIONS

Principal Investigator

ITOH Shuichi  Graduate School of Informatin Systems, Professor, 大学院・情報システム学研究科, 教授 (00017352)

Co-Investigator(Kenkyū-buntansha) HASHIMOTO Takeshi  Faculty of Electro-Communications, Associate Professor, 電気通信学部, 助教授 (10142308)
Project Period (FY) 1997 – 1998
Project Status Completed (Fiscal Year 1998)
Budget Amount *help
¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1998: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1997: ¥500,000 (Direct Cost: ¥500,000)
Keywordslossless data compression / pattern matching / Lempel-Ziv / digram / algorithm / predictive coding / recursive algorithm / bigram
Research Abstract

This project was performed during the 1997-1998 fiscal years for developing and realizing a high-speed efficient noiseless data compression algorithm based on digram string matching, We have obtained the following results :
1. The update algorithm of the dictionary is similar to that of LZMW code. In LZMW code, all the strings in the dictionary are unique, while our code could store the same string multiple times. Thus, ours can not out-perform LZMW code in compression rate. However, since the design of the algorithm is recursive in nature, the implementation is far easier and the coding speed is far faster than those of LZMW.
2. The algorithm registers longer strings in the early stage of encoding. As the result, the performance of compression improves very quickly. Therefore, it is better suited for the compression of sequence at practical length.
3. We found that it is not enough to encode the position in the dictionary by the commonly used integer encoding. We need to assign the codeword length decided by the probability of the occurrence. Since the size of the alphabet increases according to the increase of input sequence length, we have the so called "the modeling of the source with big alphabet" problem. Therefore we developed the estimation algorithm of smooth probability distribution.
Those results are expected to contribute as a basic technology for the future lossless compression schemes.

Report

(3 results)
  • 1998 Annual Research Report   Final Research Report Summary
  • 1997 Annual Research Report
  • Research Products

    (16 results)

All Other

All Publications (16 results)

  • [Publications] 奥田 敬: "文書集合からの重要語の抽出について" 第20回情報理論とその応用シンポジウム予稿集. 1. 245-248 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] 朱 蓉: "MDL原理を用いた領域分割法による画像の無歪みデータ圧縮" 第20回情報理論とその応用シンポジウム予稿集. 2. 621-624 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Qun Gong: "ステレオ航空写真からの3次元情報の抽出とデータ圧縮" 第20回情報理論とその応用シンポジウム予稿集. 2. 625-628 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] 柳澤 享: "逆問題への混合モデルの導入とステレオ画像解析への応用" 第21回情報理論とその応用シンポジウム予稿集. 1. 45-48 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] 松岡 隆仁: "折れ線モデルを利用した確率分布の推定とデータ圧縮" 第21回情報理論とその応用シンポジウム予稿集. 1. 217-220 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] 高橋 一晃: "折れ線モデルを利用した条件付き確率の推定" 第21回情報理論とその応用シンポジウム予稿集. 1. 221-224 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Takeshi OKUDA: "Study on Extracting Important Words from a Document Set" 20th SITA. vol.1. 245-248 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Rong ZHU: "Segmentation-Based Noiseless Image Coding Using MDL Principle and Progressive Transmission" 20th SITA. vol.1. 621-624 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Qun GONG: "Disparity Analysis and Data Compression of Stereo Aerial Photographs" 20th SITA. vol.2. 625-628 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Tooru YANAGISAWA: "Introduction of Mixture Models to Inverse Problems and Its Application to Stereo Image" 21st SITA. vol.1. 45-48 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Takahito MATSUOKA: "Density Estimation with Jointed Line Segments and Data Compression" 21st SITA. vol.1. 217-220 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Kazuaki TAKAHASHI: "Estimation of Conditional Probabilities with Jointed Line Segments" 21st SITA. vol.1. 221-224 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] 柳澤享,志記潤二,伊藤秀一: "逆問題への混合モデルの導入とステレオ画像解析への応用" 第21回情報理論とその応用シンポジウム予稿集. 1. 45-48 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] 松岡隆仁,志記潤二,伊藤秀一: "折れ線モデルを利用した確率分布の推定とデータ圧縮" 第21回情報理論とその応用シンポジウム予稿集. 1. 217-220 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] 高橋一晃,志記潤二,土屋英亮,伊藤秀一: "折れ線モデルを利用した条件付き確率の推定" 第21回情報理論とその応用シンポジウム予稿集. 1. 221-224 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] Wen Chen,Shuichi Itoh,Junji Shiki: "Introduction to Image Coding by Integer Wavelet" 第21回情報理論とその応用シンポジウム予稿集. 2. 815-818 (1998)

    • Related Report
      1998 Annual Research Report

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Published: 1997-04-01   Modified: 2016-04-21  

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