摘要
在近景摄影测量中,常常需要对直线特征的标志进行定位,而标志定位的精度会影响到整个测量的精度。不同特征的控制点标志,对应不同的识别方法,因此控制点标志的选择须根据不同的要求,进行综合研究分析。本文提出一种新的混合方法,首先采用Hough变换对直线特征标志进行直线检测,得到直线初值;然后采用灰度矩边缘直线拟合定位法,对标志点中心进行子像素定位。通过实验证明:经过Hough变换得到粗值的灰度矩边缘直线拟合定位法达到较高的定位精度,证明了该混合方法的有效性。
Targets based on linear feature often needs to be localized in close-range photogrammetry. However, the precision of localization will influence the precision of measurement at large. Different method of detection is adopted for the target with different feature. So it should be general analyzed to choose the targets of control point according to different need. A new mixed algorithm is proposed in the paper and the procedure that is taken in the algorithm can be divided into two steps. Firstly, the rough location of the lines is extracted with Hough algorithm. Then straight line fitting based on Gray Moment Operators for Edge Location is adopted to extract the centre of target respectively. The results of experiments show that the method for sub-pixel localization, after rough location using Hough transformation, can locates the target and obtains high precision.
出处
《测绘科学》
CSCD
北大核心
2008年第6期76-77,59,共3页
Science of Surveying and Mapping
基金
云南省教育厅科研基金资助项目(07Y10146)
红河学院博硕启动科研基金资助项目(XSS06030)
