先画了一个等边三角形，然后进行canny边缘检测，再霍夫变换提取了三角形的三条边，附带一份说明用word文件，适合初学霍夫变换的人使用-At first, this Matlab program draws a equilateral triangle. Then get its edge with canny operator and get three Hough Transfom straight line. There is an word document in this zip which is the direction.