This was also stated in my Sobel and Laplace edge detection tutorial, but I just wanted reemphasize the point of why you would want to detect edges.

这也是我在索贝尔和拉普拉斯边缘检测教程，但我只是想再次强调这一点的，为什么你会要检测的边缘。

youdao

An improved algorithm for the image edge detection based on Sobel algorithm was proposed to overcome the disadvantages, which the obtained edges of the image is thick and sensitive to the noise.

针对该算法存在检测出的边缘粗且对噪声极其敏感的缺点，提出了一种改进算法。

youdao