Journal of the Korean Data and Information Science Society

The Korean Data and Information Science Society (한국데이터정보과학회)
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Adaptive image contrast enhancement algorithm based on block approach

블럭방법에 근거한 영상의 적응적 대비증폭 알고리즘

  • Kim, Yeong-Hwa (Department of Applied Statistics, Chung-Ang University)
  • 김영화 (중앙대학교 응용통계학과)
  • Received : 2011.03.18
  • Accepted : 2011.04.20
  • Published : 2011.05.31
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Abstract

The noise caused by a variety of reasons worsens the quality of input image when we use the images reproducing device. The basic difficulty to solve this problem is that the noise and the signal are difficult to be distinguished. Contrast enhancement such as unsharp masking is one of the most important procedures to improve the quality of input images. The conventional unsharp masking enhances the images by adding their amplified high frequency components. The noise component of the input images, however, also tends to be amplified due to the nature of the unsharp masking. This paper considers the block approach for detecting niose and image feature of the input image so that the unsharp masking could be adaptively applied accordingly. Simulation results show that it is made possible to enhance contrast of the image without boosting up the noisy components by applying the proposed algorithm.

영상 구현 장치를 사용할 때, 여러가지 이유로 인하여 발생하는 잡음은 화질을 악화시키는 문제를 발생시킨다. 이러한 문제를 해결하는 과정에서의 근본적인 어려움은 영상에서 보존해야 할 신호와 제거해야할 잡음을 구분하는 것이 쉽지않다는 것이다. 언샵 마스킹과 같은 대비증폭 과정은 영상을 개선하는데 사용되는 매우 중요한 방법이다. 이 방법을 사용하면 증폭된 고주파 성분이 원래의 영상에 더하여 영상이 개선되는 효과를 얻는데, 언샵 마스킹의 특성으로 인하여 잡음 성분도 강화되어 또렷하게 부각되는 문제가 발생한다. 본 연구에서는 입력 영상에서 신호와 잡음을 효과적으로 구별하여 적응적으로 적절한 언샵 마스킹 처리를 할 수 있는 블럭방법을 제안한다. 모의실험 결과, 제안한 알고리즘을 적용함으로써 잡음 성분을 증폭시키지 않으면서 전체적인 영상의 질을 개선할 수 있는 것이 가능한 것을 확인하였다.

Keywords

References

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