The Infrared And Visible Image Fusion System And Application Research

Infrared and visible image fusion technology can extract image feature from different wavelengths, and enhance our ability of perceiving image information in the field of detection. Therefore, it is drawing great attention among civil and military fields. This paper is based on the development of infrared and visible image fusion system, and a comprehensive study of infrared and visible light imaging theory, image fusion algorithm, the design and application of fusion system is conducted.Firstly, the imaging theory of front-end detector of fusion system is studied. In view of low resolution (320×240) of existing uncooled infrared detector, new driver circuit for uncooled infrared detector with the resolution of384×288is redesigned based on UL03041. For the problem of image with low contrast after correcting infrared detector’s nonuniformity, the automatic gain algorithm is designed based on FPGA. After debugging software and hardware system, it provides a better infrared imaging platform for the following fusion system.Secondly, according to traditional image fusion algorithm, which has a great amount of information after fusion and influences our observation on target or background, a kind of imaging fusion algorithm on infrared and visible images is brought about. The algorithm’s basic idea is based on the character of human eye’s field. It takes visible image information with high resolution as background and thermal sensitivity information of infrared image as target, and then preprocesses infrared image with the improved morphological filtering to remove redundant information. Next, it fuses the contour information of infrared target and visible image. Finally, it finishes color fusion based on the human eye’s sensitivity to red and green target. The result of experiments shows that the algorithm put forward in this thesis is effective and feasible. It pursues both the detailed background and enhanced target information in fusion image, and takes less running time than wavelet and pyramidal algorithm.Then, multisource image fusion system which concludes infrared, low light level(LLL) and visible light CCD is developed. It uses binocular imaging theory of parallel optical axis to design the front-end of imaging system, to calculate imaging parallax of different view fields and parameters needed in affine transformations. It narrows down differences of different images by using bilinear interpolation algorithm and realizes rapid and real-time image registration by looking up table in hardware. The front-end imaging part and back-end control display part of fusion system are connected by fiber so as to implement remote image fusion control. Two working modes are designed:in the daytime, infrared and visible light CCD images are fused, while at night, infrared and LLL images fused. Furthermore, it checks the utility of this system by experiments.Finally, the fusion system is applied in practice. On the perspective of typical target like a flying projectile, detection ranges by visible light CCD and infrared are studied. Then, based on the temperature change on target’s surface during the flying process, computing model of the detection range by fusion system is established. With the theory of ballistics, the optimum region to detect the flying projectile in different requirements of applications is put forward.