地形(籍)图扫描纠正的精度分析

通过对某市地形 (籍 )图扫描纠正的试验 ,根据对纠正控制点的不同数量、不同分布 ,以及不同纠正数学模型的结果对比和精度分析 ,分析地形 (籍 )图纠正的各种模型和方案的优缺点 ,为地形图扫描矢量化选择合适的纠正模型和方法提供实用的参考

Accuracy Analysis of Scanned Topographic Map Image Correction

Topographic map scanning and digitization is one of major derived data capture methods in GIS.In the previous studies,efforts are made to investigate into the error characteristics and distribution in scanned map digitization.In this paper,accuracy analysis of scanned map image correction is further discussed based on the experiment method,and a practical correction model is presented.In the experiment,a topographic map is firstly scanned and the image is then corrected,the root mean square error as an indicator represented the accuracy is calculated from the coordinated differences between corresponding points in the original map and the corrected map.Several schemes are tested in the experiment,including different numbers of correction control points,different spatial distribution of control points,and different correction polynomial models.The results of each test are then compared and analyzed.The advantage and disadvantage of each correction model are analyzed.In the end,conclusions are drawn based on the case studies,which proposed practical reference in determining the pertinent model in scanned map image correction.