It is known that detecting small moving objects in astronomical image sequences is a significant research problem in space surveillance.The new theory,compressive sensing,provides a very easy and computationally cheap coding scheme for onboard astronomical remote sensing.An algorithm for small moving space object detection and localization is proposed.The algorithm determines the measurements of objects by comparing the difference between the measurements of the current image and the measurements of the background scene.In contrast to reconstruct the whole image,only a foreground image is reconstructed,which will lead to an effective computational performance,and a high level of localization accuracy is achieved.Experiments and analysis are provided to show the performance of the proposed approach on detection and localization.
提出一种基于场景模型和统计学习的行人检测算法.针对训练行人检测器时面临的动态场景的复杂性和行人样本多样性等问题,通过背景建模,从场景的背景图像上提取有限的负样本用于训练,大幅度提高了分类器的检测率,同时降低了虚警;提出一种快速弱分类器选择算法,根据正、负样本特征大小的分布和期望的检测率,直接求解特征大小的阈值范围,能够满足在线训练和更新检测器的要求;提出一种基于正样本错误率的训练算法,先根据正样本加权错误率选择弱分类器,快速提高检测率,在训练结束后调整最终分类器的加权系数,在保证检测率的同时尽可能降低虚警率.实验中构建了一个试验视频数据库和行人样本库,数据库包括雨、雪、阴影、季节变化、摄像机平移、旋转、缩放等情况,并设计实现了一个实时行人检测系统BMAT(Background modeling and Adaboost training),实验结果证明了算法的有效性.
