"Development of Algorithm for High Resolution Retinex for Image Enhancement"

Retinex is a method used for image processing. Image processing has a great role in Medical science. Medical images such as MRI, CT, Ultrasound, X-Ray has to be processed for proper diagnosis. Retinex technique can be used for the processing of these images. By retinex processing it can provide better dynamic range compression, color consistency and lightness rendition. The different methods proposed by retinex algorithm includes Light Compensation Algorithm in Color Facial Image, Retinex for bridging the gap between color images and the human observation of scenes, Color Image Contrast Enhancement by Retinex, Color Image Enhancement with Adaptive Filter. In this paper we discuss about an algorithm for frequency domain based high resolution retinex for medical image processing. Initially we introduce Fast Fourier Transform to the image. Then Gaussian filtering is done and the inverse fourier transform is taken. Next step is to apply logarithmic function. Finally gain/offset is applied to obtain the enhanced output image. The method can produce good contrast enhancement. It can be used for both color image and gray image. Since it can process gray images the medical images can be processed successfully. The output for Single Scale Retinex, Multi Scale Retinex and Multi Scale Retinex with Color Restoration are obtained.