Abstract:

With the fast development of city,to acquire and update urban fundamental data is more and more important.After the high-resolution satellite systems were put into operation,people attach more importance to the real-time,precise and authentic aerial imagery.The high-resolution aerial photographs are applied in more and more fields,and detecting buildings information from these photographs will be the important means of acquiring and updating urban fundamental information.Based on the relationship between the buildings shadow and the buildings real height of aerial imagery,the methods to extract the buildings height from their cast shadow are described in this article and the computer technology of detecting automatically buildings information from aerial imagery is realized.Taking the aerial imagery of Baoshan District of Shanghai as example,the autoptical data was compared with the computational data,and the result shows that the high-resolution imaging has a whopping potential of acquiring urban fundamental data.

Key words: high-resolution image, buildings’3D info, shadow analysis

摘要：

随着防震减灾事业的发展,对基础地理信息的要求日渐提高,利用卫星遥感影像快速补充与更新已有数据成为获取地理信息的主要方法。文中论述了太阳空间位置、卫星空间位置与建筑物空间位置对平面影像上阴影形状的约束,探讨了垂直于建筑物主方向的阴影平均宽度的统计算法和提取建筑物边界的点生长算法,给出了计算建筑物高度的数学公式,并研究出1种基于单幅高空间分辨率遥感图像数据的建筑物边界及高度快速自动生成技术。以上海市宝山区为试验区,得到了该区建筑物位置、面积和高度信息,经实地验证其试验结果可满足相应种类的灾情评估基础信息的要求。

关键词: 高分辨率影像, 建筑物三维信息, 阴影分析