Researchof Night Colorimage Enhancement Technology

The study of the technology to improve night image is a research focusing on theimage quality improvement techniques, which has a bright future in computer visionfield. Currently, the night image enhancement technology has yielded some results,but it is far from mature, so it still has great research value and development space,and attracts more and more researchers to join it.Image enhancement technique is mainly used for processing single night image.It can emphasize certain features of original image and restore the scene which wasblurred in original image. The images which are processed by image enhancementtechnique will have good qualities and can improve the reliabilities of visual perfor-mance systems. Existing methods include: histogram method, wavelet-based methods,retinex algorithm and night removal method based on the color estimation model. Themain innovations and characteristics of this paper are as follows:(1) A retinex algorithm for night color image enhancement based onL0Minimization filtering. The algorithm processes brightness image of HSV colorspace using the l0Minimization filtering. Then different strategies are used to enhancethe reflectance image and original image. At last, I compose the two part images to anew image as the final result. Under the premise of no significant amplification ofnoise, the algorithm can effectively improve the contrast and the entropy of the nightcolor images and can avoid halo artifacts. The experimental results show that theproposed algorithm has better enhancement. The image enhancement results meet thehuman eye habits well.(2) Night removal by ameliorative color estimation model and detail enhancement.The algorithm enhances the overall brightness of night image by impro ving the colorestimation model which is proposed by Huiyuan Fu. Then I enhance the detail infor-mation by detail enhancement technology based on guided filter. The experimentalresults show that the proposed algorithm can enhance night image effectively. Butthere are still some problems that need further study.