Mastering Computer Vision with TensorFlow 2.x

The Canny edge detector

The Canny edge detector uses a two-dimensional Gaussian filter to remove the noise, then applies Sobel edge detection with non-maximum suppression to pick out the maximum ratio value between the x and y gradients at any pixel point and, finally, applies edge thresholding to detect whether or not there is an edge. The following code shows Canny edge detection on a grayscale image. The min and max values are the thresholding values that compare the image gradient to determine the edges:

Canny = cv2.Canny(gray,minVal=100,maxVal=200)

The following figure shows the image of the car after applying Sobel-x, Sobel-y, and the Canny edge detector:

As we can see, Canny performs much better than Sobel in detecting the car. This ...