Kernel.Sobel

classmethod Kernel.Sobel()

Sobel edge detector

Returns:

3 x 3 Sobel kernel

Return type:

Kernel

Return the Sobel kernel for horizontal gradient

\[\begin{split}\mathbf{K} = \frac{1}{8} \begin{bmatrix} 1 & 0 & -1 \\ 2 & 0 & -2 \\ 1 & 0 & -1 \end{bmatrix}\end{split}\]

Example:

>>> from machinevisiontoolbox import Kernel
>>> K = Kernel.Sobel()
>>> K
Kernel: 3x3, min=-0.25, max=0.25, mean=0 (Sobel)
>>> K.print()
  0.12  0.00 -0.12
  0.25  0.00 -0.25
  0.12  0.00 -0.12

Note

• This kernel is an effective vertical-edge detector

• The y-derivative (horizontal-edge) kernel is K.T

References:

• P. Corke, Robotics, Vision & Control for Python, Springer, 2023, Section 11.5.1.3.

Seealso:

DGauss