三维超声系统越来越多地被应用到微创手术过程中,但是,在三维超声系统使用前必须对三维超声系统进行标定求解出超声图像平面坐标系和附属在超声探头上定位装置坐标系之间的转换关系,传统的标定方法比较繁琐,为此,开发了一种多"N"形线框标定模板.首先自动提取几张图像的特征点,利用相似三角形原理,得到超声图像特征点在模板中的同源点,利用直接求解方法快速地标定出结果.实验结果证明,整个标定过程在3min之内,满足临床应用的需求,同时,该方法同样具有高精度.

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