用于三维空间坐标系变换的7参数模型，在设计坐标系变换的各行业应用中用的最多，从数学角度来说也是最严密的转换方法。

由于结果中最多可求得七个转换参数，即三个平移参数、三个旋转参数(Ex、Ey、Ez)和一个尺度缩放因子(m)，因此，通常也被称为七参数法。 -Three-dimensional coordinate system transformation for the 7 parameter model, coordinate system transformation in the design of applications using the most, the industry, from the mathematical point of view, the conversion is the most rigorous methods. Since the results can be obtained up to seven transformation parameters, ie three translation parameters, three rotation parameters (Ex, Ey, Ez) and a zoom scale factor (m), therefore, often referred to as seven-parameter method.