二维测量（比较）

一、二维测量的一般步骤：

二、.二维测量算子
1.distance_pl
2.distance_pp
3.projection_pl
4.angle_ll

三、经典例程
1.fin：Detection of a fin

三个主要的算子：difference ，opening_rectangle1 ，closing_circle

2.measure_circles：fits circles into circular contour segments
to extract their positions and radii

3.track_wires_on_chip：
* This program shows how to iteratively track wire bondings.
* It assumes that the following values are present from a previous
* initialization phase:
* 1. Coordinates of the start and end points corresponding to the bond sites
* 2. Angle with which the wire departs from each of the above mentioned points
* 3. Approximated wire widths in pixels