FilterCanny Method

CVB.Net Documentation
Edge filter using the Canny algorithm.

Namespace:  Stemmer.Cvb.Foundation
Assembly:  Stemmer.Cvb.Foundation (in Stemmer.Cvb.Foundation.dll) Version: 14.0.0.0
Syntax
Copy
public static Image Canny(
	ImagePlane imgPlane,
	EdgeFilter edgeFilter,
	int lowerThreshold,
	int upperThreshold
)

Parameters

imgPlane
Type: Stemmer.CvbImagePlane
Image plane to be filtered.
edgeFilter
Type: Stemmer.Cvb.FoundationEdgeFilter
Edge filter method to be used.
lowerThreshold
Type: SystemInt32
Lower threshold for hysteresis thresholding.
upperThreshold
Type: SystemInt32
Upper threshold for edge detection and hysteresis thresholding.

Return Value

Type: Image
The filtered image
Exceptions
ExceptionCondition
ObjectDisposedExceptionIf the input imgPlane has already been disposed.
Remarks
The algorithm uses three stages:
  1. imgPlane is differentiated in x and y direction using the edgeFilter. From the two derivatives the direction and magnitude is computed.
  2. The directional information is simplified and then the local maximum along an edge contour is determined that lies above the upperThreshold.
  3. The contours are then traced starting from the local maximum using hysteresis thresholding with the lowerThreshold to counter broken edges.
See Also

Reference

Filter Class
Stemmer.Cvb.Foundation Namespace