canny算子进行边缘检测的源代码。

（1）首先对图像进行高斯滤波，去除噪声的影响；

（2）对滤波后图像计算梯度的幅值和方向

（3）对梯度幅值进行模极大值抑制

（4）双阈值确定边缘-canny edge detection operator to the source code. (1) First of all Gaussian image filtering to remove noise　(2) after filtering the image calculated gradient amplitude and direction of (3) of the gradient amplitude for modulus maxima suppression (4) dual-threshold determine the edge