It is necessary to explore methods to find out interpolation points for processing of substantive and dense digitized data in an automatic manner . this dissertation presents two algorithms called as " quintic - curve - method " and " sixtic - curve - method " which are applied to automatically select nodes for quintic spline interpolation ( 3 )针对大量稠密数字化数据五次样条插值的需要,开发了两种插值节点自动选择算法:五次曲线法和六次曲线法。