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기울기 차이 최소화를 통한 컬러 영상의 색수차 제거

Removing Chromatic Aberration in Color Image by Gradient Difference Minimization

  • 권지용 (연세대학교 전기전자공학과) ;
  • 강문기 (연세대학교 전기전자공학과)
  • Kwon, Ji Yong (Department of Electrical and Electronic Engineering, Yonsei University) ;
  • Kang, Moon Gi (Department of Electrical and Electronic Engineering, Yonsei University)
  • 투고 : 2016.08.24
  • 심사 : 2017.01.20
  • 발행 : 2017.02.25

초록

렌즈의 굴절률은 빛의 파장 대역에 따라 다르다. 이로 인하여 서로 다른 파장 대역의 광선들이 다른 위치에서 초점이 맞게 되어 영상의 화질이 떨어지게 되고 에지 주변에서 색수차가 발생하게 된다. 본 논문은 컬러 영상의 색수차를 제거하기 위한 방법을 제안하였다. 컬러 채널들 기울기들의 상관관계가 높다는 이론을 기반으로 하여 컬러 채널들의 기울기 차이에 대한 비용 함수를 설계하였다. 설계된 비용 함수의 에너지를 최소화하도록 하는 해를 찾음으로써 색수차가 제거된 고화질의 컬러 영상을 추정할 수 있다. 추가적으로, 제안하는 방법은 컬러 영상뿐만 아니라 다중 분광 대역 영상에 대해서도 적용 가능하다. 실험 결과에서 제안하는 방법이 효과적으로 색수차를 제거할 수 있다는 것을 보여준다.

Lenses have different refractive indices for different wavelengths of light. This is why different wavelengths of rays are focused at different positions in the focal plane. Images are blurred and noticeable colored edges appear around the objects, which is known as chromatic aberration (CA). In this paper, an algorithm for removing CA artifacts in color images is proposed. Based on the fact that the gradients of color channels are highly correlated, the differences of the gradients of the channels in edges are minimized. The cost function is designed by using the gradients of the channels. Experimental results show the good performance of the proposed algorithm in removing the CA artifacts.

키워드

참고문헌

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