Speckle Reduction Method in Wavelet Domain for OCT Image Enhancement

OCT 영상 개선을 위한 웨이블릿 영역에서의 Speckle 저감 방법

  • 이창수 (수원대학교 전자공학과) ;
  • 나지훈 (광주과학기술원 정보통신공학과) ;
  • 이병하 (광주과학기술원 정보통신공학과) ;
  • 장주완 (수원대학교 전자공학과)
  • Published : 2006.04.01


Optical coherence tomography (OCT) is high resolution medical imaging system which is obtaining image inside biological objects with non-destructive method. OCT system is based on Michelson interferometer with a reciprocating mirror in the reference arm and a biological object in the sample arm. The obtained OCT image suffers from a granular or mottled image, called speckle. Speckle is caused by random interferences between reflected coherence waves. In this paper, we propose effective speckle reduction method that uses wavelet transform. With wavelet domain image, sub-windowing and thresholding are performed. Finally, speckle reduction experiments for Misgurnus mizolepis skin and rat eye images are shown.


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