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인간 시각의 인지 특성을 이용한 영상 화질 향상 방법

Image Enhancement Using Human Visual Perception

  • 방성배 (경희대학교 전자정보대학) ;
  • 김원하 (경희대학교 전자정보대학)
  • Bang, Seangbae (College of Electronics & Information, Kyung Hee University) ;
  • Kim, Wonha (College of Electronics & Information, Kyung Hee University)
  • 투고 : 2017.12.26
  • 심사 : 2018.03.08
  • 발행 : 2018.03.30

초록

본 논문은 영상 신호의 방향을 고려하여 기존의 multiband energy scaling 방법의 문제점을 보완하면서 human visual system(HVS)에 적합한 영상 local contrast 향상 방법을 개발하였다. 기존의 multiband energy scaling 방법은 신호 방향에 대한 고려 없이 화질을 향상시켜 ringing artifact가 발생하였으나 본 논문에서는 block gradient를 사용하여 신호의 방향을 측정하고 측정된 신호 방향에 따라 주파수 신호를 향상시켜 ringing artifact의 발생 없이 화질을 향상시켰다. 또한 본 논문은 human visual system(HVS)은 각 신호의 값 하나하나 보다는 각 신호가 가지는 주파수에 성분에 민감하게 반응한다는 것을 이용하여 주파수 성분에 대한 인간 시각의 민감도를 모델링한 contrast sensitivity function(CSF)에 따라 영상의 화질을 향상시켰다. 결국 본 논문에서 제안하는 방법은 신호의 특성과 인간 시각의 특성을 모두 고려하여 영상의 화질을 향상시키기 때문에 기존의 화질 향상 방법들에 비해 영상 신호와 인간 시각 특성에 더욱 적합하게 화질을 향상시킬 수 있다.

We develop the signal processing method for adaptive implementing direction of signal and the frequency sensitivity of human visual system(HVS). Existing multiband energy scaling method makes ringing artifact because it does not consider signal direction. To solve this problem, we use block gradient for signal direction in addition to existing method. And we use the fact that frequency component of signal is more sensitive than value of signal over human eyes. we enhance the signal according to contrast sensitivity function(CSF) which is the model of frequency sensitivity of human eye. Compared that the existing analysis models only improve the efficiencies in the existing systems, the developed method can process the image signals to be more desirable and suitable to HVS.

키워드

참고문헌

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