Image Rendering Research Of Image Guidance Simulator

Image guidance simulator is a typical equip which is used to test the guidance system of image guidance weapon and to train the people who control the weapon. And how to render the image of target region realistically is one of the key of image guidance simulator. In numerous image rendering methods, the main two are virtual modeling and image mosaic, and the image mosaic has been more widely used because of its reality. Therefore, image mosaic method based on SIFT(Scale Invariant Feature Transform) features and spherical panorama mosaic are researched in this paper with the backdrop of image rendering of image guidance simulator, moreover, a visual simulation system of image guidance simulator is carried out.Firstly, aiming at the problem of image mosaic based on character points, the detection of SIFT features and image matching method ground on RANSAC(random sample consensus) are introduced, the calculate steps of image transform matrix are presented in detail and an improved Hat function blending algorithm has been advanced. All the RGB images must be transformed into HSV space and all the Hue, Saturation and Value will be adjusted into a proportional bound taking the mean value of them as the reference standard. Then the images in HSV must be transformed back into RGB form so that the Hat function blending method can be carried through. As a result, the blended image is no ghost or blur and the validity has been proved by simulation experiment.Secondly, for the sake of improving the quality of image mosaic partially, spherical panorama rendering method has been discussed. A spherical model is built and the parallelism relation between spherical coordinate and plane coordinate has been deduced. Bundle adjustment has been used in the dissertation to revise all of image transform matrix parameters jointly, avoiding the influence of accumulated error in panorama. And the improved Hat function algorithm has been extended to spherical form while Mosaicing, hence no ghosting panorama comes true.According to the research above, the visual simulation of image guidance simulator has been studied. A nearest node searching method with limitation and a proper image rendering are made use of and the seeker's visual image of long-distance missile has been simulated in real-time after it entered into last guidance phase. This system can be used to test control system and training airman. The experiment cost and risk are reduced, and the real-time missile images have important application value for image guidance study.