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FIL.GradientMagnitudeImage

Measures the strength of gradient at each pixel location.

Namespace:FilNet
Assembly:FIL.NET.dll

Syntax

C++
C#
 
public static void GradientMagnitudeImage
(
	FilNet.Image inImage,
	FilNet.GradientMaskOperator inOperator,
	FilNet.MagnitudeMeasure inMeasure,
	int inScale,
	FilNet.Image outValueImage
)

Parameters

Name Type Range Default Description
inImageFilNet.ImageInput image.
inOperatorFilNet.GradientMaskOperatorDefines how the gradient is computed.
inMeasureFilNet.MagnitudeMeasureHypotDefines how the gradient magnitude is computed. Default value: Hypot.
inScaleint<1, 16>1Scales the resulting gradient magnitudes. Default value: 1.
outValueImageFilNet.ImageGradient magnitudes of the image.

Description

The operation computes the magnitude of the intensity change at each pixel of the inImage. Firstly the selected inOperator is used to obtain two-dimensional gradient vector at each pixel. Then the magnitudes of the vectors are estimated using the inMeasure method.

Specified by inMeasure method computes magnitude (A) from horizontal gradient component (x) and vertical gradient component (y) using one of following formulas:
\[A_{Horizontal}=|x|\] \[A_{Vertical}=|y|\] \[A_{Average}=\frac{|x|+|y|}{2}\] \[A_{Sum}=|x|+|y|\] \[A_{Maximum}=Max(|x|,|y|)\] \[A_{Hypot}=\sqrt{x^{2}+y^{2} }\]

The magnitudes are multiplied by inScale factor and saturated if they exceed the greatest value of their type.

Examples

GradientMagnitudeImage performed on the sample image with inOperator = Sobel, inMeasure = Hypot.

Hardware Acceleration

This operation is optimized for SSSE3 technology for pixels of type: UINT8.

This operation is optimized for AVX2 technology for pixels of type: UINT8.

This operation is optimized for NEON technology for pixels of type: UINT8.

This operation supports automatic parallelization for multicore and multiprocessor systems.

Hardware acceleration settings may be manipulated with Settings class.

Errors

List of possible exceptions:

Error type Description
DomainError Region exceeds an input image in GradientMagnitudeImage.

Function Overrides

See also