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AVL.SelectThresholdValue Method
Selects best threshold value using the image histogram.
| Namespace: | AvlNet |
|---|---|
| Assembly: | AVL.NET.dll |
Syntax
public static void SelectThresholdValue( AvlNet.Image inImage, AvlNet.ThresholdSelectionMethod inMethod, out float outThresholdValue, out float[] diagThresholdRatings, out float[] diagBackgroundPixelsFraction, out float[] diagForegroundPixelsFraction )
Parameters
| Name | Type | Range | Default | Description | |
|---|---|---|---|---|---|
 | inImage | AvlNet.Image | Input image. | ||
| inMethod | AvlNet.ThresholdSelectionMethod | Method used to select the best threshold. | ||
 | outThresholdValue | float | Best threshold separating background pixels from foreground pixels. | ||
 | diagThresholdRatings | float | Contains ratings gained if that threshold would be chosen. | ||
| diagBackgroundPixelsFraction | float | Fraction of pixels that are darker than the index value. | ||
| diagForegroundPixelsFraction | float | Fraction of pixels that are brighter than the index value. |
Description
The operation estimates an intensity threshold value that discriminates foreground pixels from background pixels in inImage.
Note that to provide meaningful results it is required that the image in fact consists of foreground and background components that strongly differ in brightness.
Examples
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SelectThresholdValue performed on the sample image (on the left) with inMethod = ClusteringKittler yields outThresholdValue = 189.5. Pixels of the input image brighter than 189.5 are presented on the right.
