수리형태학적 분석을 통한 계단응답 추출 및 반복적 정칙화 방법을 이용한 점확산함수 추정 및 영상 복원

Morphology-Based Step Response Extraction and Regularized Iterative Point Spread Function Estimation & Image Restoration

  • 박영욱 (중앙대학교 첨단영상대학원) ;
  • 전재환 (중앙대학교 첨단영상대학원) ;
  • 이진희 (중앙대학교 첨단영상대학원) ;
  • 강남오 (중앙대학교 첨단영상대학원) ;
  • 백준기 (중앙대학교 첨단영상대학원)
  • Park, Young-Uk (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University) ;
  • Jeon, Jae-Hwan (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University) ;
  • Lee, Jin-Hee (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University) ;
  • Kang, Nam-Oh (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University) ;
  • Paik, Joon-Ki (Dept. of Image Engineering, Graduate School of Advanced Image Science, Multimedia, and Film, Chung-Ang University)
  • 발행 : 2009.11.25

초록

본 논문은 수리형태학적 분석을 통한 계단응답 추출 및 반복적 정칙화 방법을 이용한 점확산함수 추정 방법을 제안한다. 제안된 점확산함수 추정 기법은 입력 영상의 윤곽을 추출하기 위하여 캐니 에지 추출법을 사용하고, 윤곽에 대한 수리형태학적 분석을 위해서 Hit-or-Miss 변환을 통해 추정 조건을 만족하는 수평 및 수직 에지를 추출한다. 이렇게 추출된 에지들을 평탄화 및 정규화 시켜서 최적의 계단응답으로 만들고, 반복적 정칙화 방법을 통해 점확산함수를 추정하는 과정을 보인다. 또한 추정된 점확산함수를 사용하여 영상 복원한 결과를 보인다. 제안하는 점확산함수 추정 방법은 기계적 초점 렌즈를 사용하지 않는 디지털 자동초점 시스템에 적용하여 디지털 입력 장치의 부가가치를 높이는데 기여할 수 있다.

In this paper, we present morphology-based step region extraction and regularized iterative point-spread-function (PSF) estimation methods. The proposed PSF estimation method uses canny edge detector to extract the edge of the input image. We extract feasible vertical and horizontal edges using morphology analysis, such as the hit-or-miss transform. Given extracted edges we estimate the optimal step-response using flattening and normalization processes. The PSF is finally characterized by solving the equation which relates the optimal step response and the 2D isotropic PSF. We shows the restored image by the estimated PSF. The proposed algorithm can be applied a fully digital auto-focusing system without using mechanical focusing parts.

키워드

참고문헌

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