基于霍夫变换的外形检测算法的实现，包括图像读取与显示、彩色图像转化为灰度图、灰度图二值化、膨胀腐蚀、图像轮廓提取、线性图形检测以及椭圆检测-Shape detection algorithm based on Hough transform implementation, including the image read and display color images into grayscale, grayscale binary and expansion corrosion image