Emgu CV Library Documentation
Sobel Method (xorder, yorder, apertureSize)
NamespacesEmgu.CVImage<(Of <(TColor, TDepth>)>)Sobel(Int32, Int32, Int32)

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Calculates the image derivative by convolving the image with the appropriate kernel: dst(x,y) = dxorder+yodersrc/dxxorder?dyyorder |(x,y) The Sobel operators combine Gaussian smoothing and differentiation so the result is more or less robust to the noise. Most often, the function is called with (xorder=1, yorder=0, aperture_size=3) or (xorder=0, yorder=1, aperture_size=3) to calculate first x- or y- image derivative.
Declaration Syntax
C#Visual BasicVisual C++
public Image<TColor, TDepth> Sobel(
	int xorder,
	int yorder,
	int apertureSize
)
Public Function Sobel ( _
	xorder As Integer, _
	yorder As Integer, _
	apertureSize As Integer _
) As Image(Of TColor, TDepth)
public:
Image<TColor, TDepth>^ Sobel(
	int xorder, 
	int yorder, 
	int apertureSize
)
Parameters
xorder (Int32)
Order of the derivative x
yorder (Int32)
Order of the derivative y
apertureSize (Int32)
Size of the extended Sobel kernel, must be 1, 3, 5 or 7. In all cases except 1, aperture_size xaperture_size separable kernel will be used to calculate the derivative.
Return Value
The result of the sobel edge detector

Assembly: Emgu.CV (Module: Emgu.CV) Version: 1.3.0.0 (1.3.0.0)