Sobel filter kernel

1. What are Sobel kernels?
2. How does Sobel kernel work?
3. What is Sobel filter used for?
4. Which kernel is used for edge detection?

What are Sobel kernels?

A kernel is just a fancy name for a small matrix.

This small matrix is 3×3 (3 rows and 3 columns). It happens to be the kernel used in the Sobel algorithm to calculate estimates of the derivatives in the vertical direction of an image.

How does Sobel kernel work?

The Sobel filter is used for edge detection. It works by calculating the gradient of image intensity at each pixel within the image. It finds the direction of the largest increase from light to dark and the rate of change in that direction.

What is Sobel filter used for?

The Sobel operator, sometimes called the Sobel–Feldman operator or Sobel filter, is used in image processing and computer vision, particularly within edge detection algorithms where it creates an image emphasising edges.

Which kernel is used for edge detection?

13.4.

To obtain the edge information, a differential convolution kernel is used. Of these kernels, Sobel convolution kernels are used for horizontal and vertical edge detection.