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

The Institute of Electronics and Information Engineers (대한전자공학회)
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Post-processing Technique Based on POCS Using Wavelet Transform

웨이브릿 변환을 이용한 POCS 기반의 후처리 기법

  • Kwon Goo-Rak (School of Electrical Engineering, Korea University) ;
  • Kim Hyo-Kak (School of Electrical Engineering, Korea University) ;
  • Kim Yoon (Dept. of Electrical and Computer Engineering, Kangwon National University) ;
  • Ko Sung-Jea (School of Electrical Engineering, Korea University)
  • 권구락 (고려대학교 전기전자전파공학부) ;
  • 김효각 (고려대학교 전기전자전파공학부) ;
  • 김윤 (강원대학교 전기전자정보통신공학부) ;
  • 고성제 (고려대학교 전기전자전파공학부)
  • Published : 2006.05.01
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Abstract

In this paper, we propose a new post-processing method, based on the theory of the projection onto convex sets (POCS) to reduce the blocking artifacts in decoded images. We propose a few smoothness constraint set (SCS) and its projection operator in the wavelet transform (WT) domain to remove unnecessary high-frequency components caused by blocking artifacts. We also propose a new method to find and preserve the original high frequency components of the image edge. Experimental results show that the proposed method can not only achieve a significantly enhanced subjective quality, but also have the PSNR improvement in the output image.

본 논문에서는 복원된 영상에서 블록현상을 제거하기 위해 POCS 이론을 기반으로 효율적인 후처리 기법을 제안한다. 블록 현상을 나타내는 불필요한 고주파성분을 제거하기 위해 웨이브렛 변환으로 효과적인 SCS 및 그 투영자를 제안한다. 또한 원 영상에서 에지로 나타나는 고주파성분은 찾아서 유지하는 방법도 제안한다. 실험결과로 제안하는 방법은 향상된 주관적 화질뿐만 아니라, 복원된 출력 영상에서의 PSNR이 향상됨을 알 수 있다.

Keywords

References

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