c# - How to find arcs or open curves in a line drawing?

Question

I'm facing a problem which I thought was simple but now it's tearing up my scalp.

Given a line drawing, is it possible to find the number of arcs or curves in the drawing? If possible at all, what would be the best way to go about this?

Example:

The above image has two curves but I have been trying all sorts of algorithms to locate them with no success. Any thoughts?

Answer 1

我建议以下问题：

我们可以在绘图上取任意一点，然后开始向任意方向移动（根据 - 取第二个绘图点，第三个，第四个，……）在每一步之后，我们检查：我们是否已经到过这一点。

如果是 - 绘图已关闭。

如果没有更多要检查的点 - 绘图未关闭。