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A New Focus Measure Method Based on Mathematical Morphology for 3D Shape Recovery

3차원 형상 복원을 위한 수학적 모폴로지 기반의 초점 측도 기법

  • ;
  • 최영규 (한국기술교육대학교 컴퓨터공학부)
  • Received : 2016.04.05
  • Accepted : 2016.08.05
  • Published : 2017.01.31

Abstract

Shape from focus (SFF) is a technique used to reconstruct 3D shape of objects from a sequence of images obtained at different focus settings of the lens. In this paper, a new shape from focus method for 3D reconstruction of microscopic objects is described, which is based on gradient operator in Mathematical Morphology. Conventionally, in SFF methods, a single focus measure is used for measuring the focus quality. Due to the complex shape and texture of microscopic objects, single measure based operators are not sufficient, so we propose morphological operators with multi-structuring elements for computing the focus values. Finally, an optimal focus measure is obtained by combining the response of all focus measures. The experimental results showed that the proposed algorithm has provided more accurate depth maps than the existing methods in terms of three-dimensional shape recovery.

Shape from focus (SFF) 기법은 카메라 렌즈를 다양한 초점 거리로 놓고 촬영한 영상을 이용해 물체의 3차원 정보를 추출하는 방법이다. 이 논문에서는 미소 객체(microscopic object)의 3차원 깊이 정보를 추출하기 위해 수학적 모폴로지의 기울기 연산자를 이용하는 새로운 SFF방법을 제안한다. 전통적으로 SFF 기법에서는 초점의 품질을 측정하기 위해 하나의 초점 측도(focus measure)를 사용한다. 그러나 미소 객체의 복잡한 형태와 텍스쳐 특성에 따라 하나의 초점 측도만을 사용하는 것은 충분하지가 않은데, 본 논문에서는 향상된 초점 측도를 위해 다수의 형태소(multi-structuring elements)를 사용하는 모폴로지 연산자를 사용하는 방법을 제안한다. 최종적으로 모든 초점 측도 결과를 통합하여 최적의 깊이 맵을 계산하게 된다. 실험을 통해 제안된 알고리즘이 기존의 방법들에 비해 3차원 형상 복원 측면에서 더 정밀한 깊이 맵을 제공하는 것을 알 수 있었다.

Keywords

References

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