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ImageCorrelation
Computes the correlation of pattern and image.
| Name | Type | Description | |
|---|---|---|---|
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inImage | Image | Input image |
|
inPatternImage | Image | Pattern to be compared with input image |
|
inRoi | Region* | Range of pixels to be processed |
|
inCorrelationMeasure | CorrelationMeasure | Measure of correlation |
 |
outCorrelation | Real | Value 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 Image Conversions category.
Examples
 |
 |
Normalized cross correlation between the sample images equals 0.919.
|
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Normalized cross correlation between the sample images equals 0.798.
Errors
This filter can throw an exception to report error. Read how to deal with errors in Error Handling.
List of possible exceptions:
| Error type | Description |
|---|---|
| DomainError | Not supported correlation measure in ImageCorrelation. |
Complexity Level
This filter is available on Advanced Complexity Level.
See Also
- ImageCorrelationImage – Computes an image of correlation between a pattern and the input image at each possible location.
- LocateMultipleObjects_NCC – Finds all occurrences of a predefined template on an image by analysing the normalized correlation between pixel values.
