Using HSV space real-color image enhanced by homomorphic filter in two channels
Mingquan Zhou · Computer Engineering and Applications Journal · 2009
It provides good dynamic range compression in each red,green,and blue(RGB) channel of real-color image,but it fails in color rendition.In this paper,a real-color image is transformed from RGB space to HSV space at first.Then saturation channel is enhanced by Butterworth high-pass homomorphic filter and lightness channel is enhanced by Gaussian high-pass homomorphic filter.In addition,a new method how to fix on the cut-off frequency of high-pass filter in homomorphic enhancement is studied and the ratio coefficient of high-pass filter is explained.Experiments show the compression of real-color image dynamic range is obviously effective and it successes in color rendition.