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FIL.ImageCorrelation

Computes the correlation of pattern and image.

Namespace:FilNet
Assembly:FIL.NET.dll

Syntax

C++
C#
 
public static void ImageCorrelation
(
	FilNet.Image inImage,
	FilNet.Image inPatternImage,
	NullableRef<FilNet.Region> inRoi,
	FilNet.CorrelationMeasure inCorrelationMeasure,
	out float outCorrelation
)

Parameters

Name Type Range Default Description
inImageFilNet.ImageInput image.
inPatternImageFilNet.ImagePattern to be compared with input image.
inRoiFilNet.NullableRef<FilNet.Region>Range of pixels to be processed. Default value: ftl::NIL.
inCorrelationMeasureFilNet.CorrelationMeasureMeasure of correlation.
outCorrelationfloatValue of correlation of pattern and image.

Description

The operation computes the correlation between two images using the selected measure.

  • If the inCorrelationMeasure is set to CrossCorrelation then the resulting outCorrelation is the sum of products of corresponding pixel values of the images.
  • If the inCorrelationMeasure is set to NormalizedCrossCorrelation then the resulting outCorrelation is the normalized sum of products of corresponding pixel values of the images. This value always lies in closed interval \([-1,1]\), with \(1\) indicating the images ideal correlation.

The operation requires that the images being processed have equal format and dimensions, otherwise an error with appropriate description occurs. To obtain an image of desired dimensions one can use ResizeImage or CropImage filter. To alter the format of an image one can use filters contained in ImageConversions category.

Examples

Normalized cross correlation between the sample images equals 0.919.

Normalized cross correlation between the sample images equals 0.798.

Errors

List of possible exceptions:

Error type Description
DomainError Not supported correlation measure in ImageCorrelation.

Function Overrides

See also