Gaussian Distributive Filtering in Histogram Equalization

Following the rapid advances in digital technologies, more and more consumer electronic devices, such as cell phones and PDAs, are equipped with built-in camera modules. In order to be cost-effective, optoelectronics components used in such devices are usually not sophisticated enough to support professional photographing. Pictures taken by such devices tend to be of unsatisfiable quality under poor shooting conditions, and post-processing becomes very useful in improving the quality of such images. Among various post-processing techniques of digital images, histogram equalization performs contrast adjustment of an image by evenly distributing its brightness values. In digital images, however, the phenomenon of ``quantization´´ prevents ideal equalization of the histogram. To compensate for such drawback, we propose a technique named Gaussian Distributive Filter to serve as a post-enhancement method for histogram equalization techniques to fine-tune the histogram of an image. Experimental results show our proposed technique to be promising.