You are here: Start » AVL.NET » Function Reference » Image » Image Features » AVL.ImageMoment

AVL.ImageMoment

Computes the selected moment of an image in regular and normalized (divided by sum of pixel values) variant.

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void ImageMoment
(
	AvlNet.Image inImage,
	NullableRef<AvlNet.Region> inRoi,
	AvlNet.ImageMomentType inMomentType,
	bool inCentral,
	out float outMoment,
	NullableValue<float> outNormMoment
)

Parameters

Name Type Range Default Description
inImageAvlNet.ImageInput image.
inRoiAvlNet.NullableRef<AvlNet.Region>Range of pixels to be processed. Default value: atl::NIL.
inMomentTypeAvlNet.ImageMomentType
inCentralbool
outMomentfloat
outNormMomentAvlNet.NullableValue<float> Can be null to skip this parameter calculation.

Description

The operation computes the mathematical features of an image called moments. Those are sums computed as follows:

\[ \begin{aligned} Moment_{0,0}(Image,Roi) &= \sum_{p \in Roi} Image(p_x,p_y) \cdot 1 \\ Moment_{0,1}(Image,Roi) &= \sum_{p \in Roi} Image(p_x,p_y) \cdot p_y \\ Moment_{1,0}(Image,Roi) &= \sum_{p \in Roi} Image(p_x,p_y) \cdot p_x \\ Moment_{0,2}(Image,Roi) &= \sum_{p \in Roi} Image(p_x,p_y) \cdot p_y^2 \\ Moment_{1,1}(Image,Roi) &= \sum_{p \in Roi} Image(p_x,p_y) \cdot p_x p_y \\ Moment_{2,0}(Image,Roi) &= \sum_{p \in Roi} Image(p_x,p_y) \cdot p_x^2 \end{aligned} \]

The summing is conducted over all pixels in inRoi region, while \( p_x \) and \( p_y \) denote, accordingly, x and y coordinate of a pixel.

When inCentral parameter is set, the image is shifted before computations, so that its mass center is at location (0,0).

Hardware Acceleration

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 Black image on input in ImageMoment.
DomainError Empty region on input in ImageMoment.
DomainError Region exceeds an input image in ImageMoment.

Function Overrides

See also