Research Of Image Enhancement Algorithms And Its Application Under The Conditions Of The Fog And Haze

Image processing technology has been widely used and has made tremendous achievements in military, transportation and other fields in recent years. The images under the conditions of the foggy and haze are so vague and dim, which greatly reduces the useful information in the images and brings a lot of trouble to people's life. So the study on the technique of image enhancement under the conditions of the foggy weather has an important meaning. The thesis mainly researches the algorithm of image enhancement, especially under the conditions of the foggy and hazes.The Retinex algorithm is a new kind of image enhancement method. Comparing with the conventional enhancement methods, the Retinex has several features, such as color constancy, processing quickly, and good visual characteristics etc. Thus the thesis mainly researches the technique of image enhancement under the conditions of the foggy and hazes by the usage of Retinex algorithm and applies the Retinex algorithm in traffic management and aviation shooting.The thesis researches Retinex algorithm on the basis of color consistence theory. It firstly focuses on the research of global Retinex algorithm, and proposes an improved algorithm by analyzing the shortcomings of global Retinex algorithm.Then the paper divides local Retinex algorithms into three kinds of methods, which are SSR (single scale Retinex algorithm), MSR (multi-scale Retinex algorithm) and MSRCR (with the color recovery of multi-scale Retinex algorithm).implements by the research of local Retinex algorithms. The paper proposes the MSR algorithm based on mathematical morphology and MSRCR algorithm based on gaussian recursive filtering by the research of MSR and MSRCR algorithms.Finally the paper applies the several enhancement algorithms in the license plate identification, and evaluates the algorithms by the recognition rate of the license plate numbers.The paper compares the several enhancement algorithms by the usage of three kinds of recognition algorithm of the license plate.Then the paper applies the several enhancement algorithms in aviation shooting, and analyses the several enhancement algorithms by the subjective and objective evaluation index.