Authors : Mi Deling , Feng Peng , Pan Yingjun , Pan Yingjun and Jin Wei
Abstract: We present in this study, a new Multi-scale Geometrical Analysis method for ophthalmic image contrast enhancement based on the contourlet transform. The contourlet transform has better performace in representing edges than wavelets due to its anisotropy and directionality and is therefore, well-suited for multiscale edge enhancement. We modify the contourlet coefficients in corresponding subband and take the noise into account for more precisely reconstruction and better visualization. We compare this approach with enhancement based on the curvelet transform, and the traditional Histogram Stretching (HS). Our findings are that contourlet based enhancement out-performs other enhancement methods on low contrast and dynamic range images and can clearly identify the vessels and nerves in ophthalmic image.
Mi Deling , Feng Peng , Pan Yingjun , Pan Yingjun and Jin Wei , 2007. Contrast Enhancement in Retinal Image via Multi-Scale Geometrical Analysis . Asian Journal of Information Technology, 6: 986-990.