光谱差异是提取建筑物阴影信息的一个重要依据。基于ALOS卫星图像阴影与建筑物高度关系的分析,文章阐述了依据阴影来估算建筑物高度的原理和方法,辅以数据融合的方法,利用多光谱影像中的光谱差异从ALOS全色图像中准确提取阴影信息,从而建立一种基于图像阴影提取城市建筑物高度及分布信息的标准化流程。同时,在天津的城市建筑物高度获取试验中,建筑物高度提取精度的抽样验证率达到87.6%,初步显示出了ALOS卫星数据在城市建筑物高度测量方面的巨大潜力。
Spectral difference is an important aspect for extracting shadows of buildings.Based on the analysis of the relationship between the building heights and the shadows in ALOS Images,the paper presents the principle and the method for building heights estimation in a city from the shadows of an image,and works out a feasible approach to determining shadow zones in a panchromatic ALOS Images.It has also contributed a standard process for extracting buildings distribution information of different heights in a city from the shadows in a panchromatic ALOS Images.A result with about 87.6% accuracy has been achieved while applying this technique to Tianjin City,which has demonstrated prospective applications of satellite remote sensing to urban purposes.