Journal of the Institute of Electronics and Information Engineers (전자공학회논문지)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Approximated Constrained Least Squares Filter for Real-Time Directionally Adaptive Image Restoration

제약적 최소 제곱 필터의 근사화를 이용한 실시간 방향 적응적 영상복원

  • Cho, Changhun (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University) ;
  • Jeon, Jaehwan (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University) ;
  • Paik, Joonki (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University)
  • 조창훈 (중앙대학교 첨단영상대학원) ;
  • 전재환 (중앙대학교 첨단영상대학원) ;
  • 백준기 (중앙대학교 첨단영상대학원)
  • Received : 2013.08.02
  • Accepted : 2013.11.21
  • Published : 2013.12.25
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Abstract

In this paper we present approximated constrained least squares filter for real-time directionally adaptive image restoration. The proposed method makes a hardware implementation easier for real-time image restoration because of reducing the filter size. Furthermore, for directional adaptive image restoration, this paper estimates the local orientation by analyzing the covariance matrix and applies to approximated constrained least squares filter. Experimental results show that the proposed method is sharper and less artifacts than existing methods.

본 논문에서는 절단된 제약적 최소 제곱 필터를 이용하여 방향 적응적으로 영상을 복원하는 방법을 제안한다. 제안하는 영상복원 필터는 공간영역에서 이론적으로 영상 전체의 크기를 갖는 제약적 최소 제곱(constrained least squares; CLS) 필터를 Maxwell-Boltzmann 커널을 사용하여 절단한 유한 임펄스 응답(finite impulse response; FIR) 필터의 구조로 실시간 영상복원을 가능하게 한다. 또한 화소 단위로 공분산 행렬을 분석하여 방향성을 추정하여, 화소마다 필터의 계수를 적응적으로 생성하여 방향 적응적으로 영상을 복원한다. 실험결과를 통해 기존의 알고리듬에 비해 제안된 방법이 선명하고 부작용(artifacts)이 적은 결과를 얻는 것을 검증하였다.

Keywords

References

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