The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
3. CONCLUSIONS. 
The method processed the statistics of building main direction, 
and planned the segments in accordance with the main direction, 
so we can able to control the shape of the top of buildings good. 
Taking the straight line of detected edge as reference, it has a 
relative strong anti-noise capability. This method is relatively 
stable, high accurate. Extracting is more dependent on the effect 
of edge detecting, if the edge is not clear, shadow and the 
surrounding features and buildings are very alike, the detection 
result is not satisfied or the outcome is wrong. In addition, 
during the line extension because it is difficult to find a method 
of parallel extent, which can only divide region into rectangle, 
and there are no unique guidelines of merger, results in the 
extraction incomplete to the multi-angle type. 
REFERENCE 
Zhang Yu, Zhang Zuxun, Zhang Jianqing, J., 2000 The fast 
Semi-automation extraction of buildings depends on 
Geometrical restriction and image segmentation.. Transaction of 
Wu Han Survey Scientific University, Vol.25(3), pp. 239-242 
Yang Yijun, Zhao Rongchun, WangWenbing,J.2003 The 
Automatic detect of artificial buildings on image,pp.214-218 
Tao Wenbing, LiuJian.,J, 2001A new automatic extraction of 
urban buildings on navigate image, 26(7), pp.867-873 
TianYan, Zhangjun, Tao Wenbing,J, 2002 The Extraction of 
city geometrical Information. Institute of Image Recognition 
and Artificial Intelligence of HuaZhong Scienfic University. 
Technical Report. ,30(4),pp, 120-124 
ChenGuang„J,2003 Building recognition and change detection 
on remote sensing image. Theory of master ’ s degree of 
NanKing Science University,35(5)pp. 200 
ACKNOWLEDGEMENT 
Our research project i s supported by the “ National S cientific 
Fund Program (No. 40771159)”, the “ University d octor 
disciplines S cientific Fund Program of Ministry of Education 
(No. 20070 147008 )” , the “Open Research Fund Program of 
the State Key Laboratory of Information Engineering in 
Surveying, Mapping and Remote Sensing of Wuhan 
University (No. WKL(07)0303 )” , and the “42nd Postdoctor 
S cientific Fund Program (No. 20070420918 )” . 
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