Press the ‘o’ key: show the original webcam/video frame.
Press the ‘x’ key: show the Sobel gradient in the x direction.
Press the ‘y’ key: show the Sobel gradient in the y direction.
Press the ‘m’ key: show the Sobel magnitude of the gradient.
Press the ‘s’ key: show the result of Sobel + thresholding edge detection.
Press the ‘l’ key: apply Laplacian of Gaussian (LoG)edge detector.
press the ‘+’ key: increase smoothing parameter sigma.
Press the ‘-’ key: Decrease smoothing parameter sigma.
Press the ‘q’ key: quit the program