EdgeDetectSobelFilter Class

Defines a EdgeDetectSobelFilter effect to process the image. This class cannot be inherited.

C++

public: class EdgeDetectSobelFilter : public BaseFilter;

public sealed class EdgeDetectSobelFilter : BaseFilter;

Visual Basic

Public sealed Class EdgeDetectSobelFilter
Inherits BaseFilter

Remarks

Edge detecting an image significantly reduces the amount of data and filters out useless information, while preserving the important structural properties in an image. There are many ways to perform edge detection. However, the majority of different methods may be grouped into two categories, gradient and Laplacian. The gradient method detects the edges by looking for the maximum and minimum in the first derivative of the image. The Laplacian method searches for zero crossings in the second derivative of the image to find edges. An edge has the one-dimensional shape of a ramp and calculating the derivative of the image can highlight its location.

The Sobel operator performs a 2-D spatial gradient measurement on an image. The Sobel edge detector uses a pair of 3x3 convolution masks, one estimating the gradient in the x-direction (columns) and the other estimating the gradient in the y-direction (rows).