A Comparative Study of Image Enhancement Techniques for Iris Images

Abstract: Image Enhancement techniques which improve the quality (clarity) of images for human viewing, removing blurring and noise, increasing contrast, and revealing. This enhancer accommodates most of the image enhancement techniques with a user input interface, which can be used to combine two or more of these techniques. The existing techniques of image enhancement can be classified into three categories: Spatial Domain, Frequency domain and Histogram Equalization. In spatial domain methodpixel values may be modified according to rules that depend on the original pixel value, frequency domain techniques are suited for processing the image according to the frequency content and histogram equalization assigns the intensity values of pixels in the input image such that the output image contains a uniform distribution of intensities. Keywords?Image Enhancement, Spatial based domain enhancement, Frequency based domain enhancement, Histogram Equalization.