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

The Institute of Electronics and Information Engineers (대한전자공학회)
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Postprocessing Method for Quantization Noise Reduction Using Block Classification and Adaptive Filtering

블록 분류와 적응적 필터링을 이용한 후처리에서의 양자화 잡음 제거 방법

  • 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)
  • 이승진 (경북대학교 전자전기공학부) ;
  • 이석환 (경북대학교 전자전기공학부) ;
  • 권성근 (경북대학교 전자전기공학부) ;
  • 이종원 (경북대학교 전자전기공학부) ;
  • 이건일 (경북대학교 전자전기공학부)
  • Published : 2001.07.01
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Abstract

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.

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.

Keywords

References

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