대한전자공학회논문지SP (Journal of the Institute of Electronics Engineers of Korea SP)

대한전자공학회 (The Institute of Electronics and Information Engineers)
권호 표지

블록 분류와 적응적 필터링을 이용한 후처리에서의 양자화 잡음 제거 방법

Postprocessing Method for Quantization Noise Reduction Using Block Classification and Adaptive Filtering

  • 이승진 (경북대학교 전자전기공학부) ;
  • 이석환 (경북대학교 전자전기공학부) ;
  • 권성근 (경북대학교 전자전기공학부) ;
  • 이종원 (경북대학교 전자전기공학부) ;
  • 이건일 (경북대학교 전자전기공학부)
  • Lee, Seung-Jin (School of Electronic & Electrical Engineering, Kyungpook National University) ;
  • Lee, Seok-Hwan (School of Electronic & Electrical Engineering, Kyungpook National University) ;
  • Gwon, Seong-Geun (School of Electronic & Electrical Engineering, Kyungpook National University) ;
  • Lee, Jong-Won (School of Electronic & Electrical Engineering, Kyungpook National University) ;
  • Lee, Geon-Il (School of Electronic & Electrical Engineering, Kyungpook National University)
  • 발행 : 2001.07.01
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초록

본 논문에서는 블록 분류와 적응적 필터링을 이용하여 블록 기반 부호화에서의 양자화 잡음을 제거하는 후처리 방법을 제안하였다. 제안한 방법에서는 블록 분류, 적응적인 블록 간 필터링, 및 블록 내 필터링의 단계로 이루어진다. 먼저, 각 블록을 8x8 DCT 계수 분포에 따라 7개의 클래스로 분류하고, 인접한 두 클래스 정보에 따라 적응적인 블록 간 필터링을 수행한다. 그리고 에지 블록으로 분류된 블록에 대하여 에지맵을 이용한 블록 내 필터링을 수행한다. 실험결과로부터 제안한 방법이 기존의 방법에 비하여 객관적 화질 측면에서는 유사하지만, 주관적 화질 측면에서 보다 우수함을 확인하였다.

In this paper, we proposed a postprocessing algorithm for quantization effects reduction in block coded images using the block classification and adaptive filtering. The proposed method consists of classification, adaptive inter-block filtering, and intra-block filtering. First, each block is classified into one of seven classes based on the characteristics of 8$\times$8 DCT coefficients. Then each block boundary is filtered by adaptive inter-block fitters according to the block classification. finally for blocks which are classified into edge block, intra-block filtering is performed. Experimental results show that the proposed method gives better results than the conventional methods from both a subjective and an objective viewpoint.

키워드

참고문헌

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