The Panoramic Map Generation Wide Area Surveillance System Technology Research

In this dissertation, we discuss the problem of panorama generation for the wide-area surveillance system. In the process of panorama generation, image registration methods are the key of our research.We use PTZ(pan-tilt-zoom)camera to acquire image sequence. The type of the mapping functions should be chosen according to the a priori known information about the acquisition process and expected image degradations. First of all, we analyze the acquisition process and then choose the 8-parameter perspective mapping function as the mapping function for the image sequence. Secondly, we analyze the relationship between the camera movement and the mapping function. We find that the mapping function is related not only to the camera movement but also to the depth of the scene. So the use of image registration is necessary for the panorama generation. There are many image registration methods, and each method is related to a type of mapping function. We need to use feature-based methods to estimate the parameters of the perspective mapping function.According to the characteristic of the image sequence, we propose a registration method which is based on Harris corner and is invariant to rotation. Firstly, we extract Harris corners from images and construct a rotation-invariant descriptor for each of them. Then we match these descriptors and eliminate the wrongs. We estimate the parameters of the mapping function with least squares iterative estimation. According to the mapping function we can align the adjacent pair of images. And then we align all of the images by the product of mapping functions. So we can generate the panorama by suturing all of the aligned images. The registration method which is based on Harris corner and is invariant to rotation is proved to be effective and robust in experiment...