摘要
航空影像中 ,垂直边缘对建筑物提取具有重要意义。为快速准确地提取垂直边缘 ,依据航空摄影测量学的有关知识 ,利用摄影测量成像模型推导出垂直边缘灭点位置 ,并结合物方空间几何约束和图像空间边缘信息 ,采用一种自适应模糊 Hough变换算法 ,实现了建筑物垂直边缘的自动提取。实验证明 ,该算法是行之有效的。
In aerial images, vertical line is of significant use for building extraction, which provides not only the key and reliable evidence for building existence, but also the height of buildings. In this paper, in order to extract vertical lines, a simple method for determining the vanishing point of vertical lines is first analyzed based on the knowledge about the aerial photogrammetry. It is demonstrated that, suppose the imaging plane in aerophotograph is approximately parallel with the horizontal plane, the central point of an aerial image is approximate to the vanishing point of vertical lines. This information provides a geometrical constraint for vertical line extraction in object space and makes the automatic extraction of vertical lines very straightforward and simple. Second, in order to improve the efficiency and precision of line detection and to acquire the complete description of vertical lines (e.g. line parameters, pixel positions, and length etc.), the adaptive fuzzy Hough transform, which combines the geometrical constraint in object space and gradient orientation information in image space adequately to achieve an excellent performance, is adopted to extract vertical lines automatically. Lastly, the Experimental results are given to indicate that the presented algorithm is effective and efficient for real\|time applications, and provides a key evidence and clue for automatic building extraction from aerial images.
出处
《中国图象图形学报（A辑）》
CSCD
北大核心
2004年第9期1049-1054,共6页
Journal of Image and Graphics
基金
国家自然基金项目 (60 172 0 66)
国家"863"计划项目 (2 0 0 1AA13 60 70 )
