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AVL.CheckPresence_PixelAmount

Verifies object presence by analysing the amount of pixels that meet the specified criteria.

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void CheckPresence_PixelAmount
(
	AvlNet.Image inImage,
	AvlNet.ShapeRegion inRoi,
	AvlNet.CoordinateSystem2D? inRoiAlignment,
	AvlNet.HSxColorModel inColorModel,
	int inBeginHue,
	int inEndHue,
	int inMinSaturation,
	int? inMaxSaturation,
	float? inMinBrightness,
	float? inMaxBrightness,
	float inMinAmount,
	float inMaxAmount,
	out bool outIsPresent,
	out float outAmount,
	AvlNet.Region outForeground,
	AvlNet.ShapeRegion outAlignedRoi,
	AvlNet.Image diagHsxImage
)

Parameters

Name Type Range Default Description
inImageAvlNet.ImageInput image.
inRoiAvlNet.ShapeRegionLocation at which object presence is being checked.
inRoiAlignmentAvlNet.CoordinateSystem2D?Adjusts the region of interest to the position of the inspected object. Default value: atl::NIL.
inColorModelAvlNet.HSxColorModelSelected color model.
inBeginHueint<0, 255>0Begin of the range of acceptable hue. Default value: 0.
inEndHueint<0, 255>255End of the range of acceptable hue. Default value: 255.
inMinSaturationint<0, 255>128Lowest acceptable saturation. Default value: 128.
inMaxSaturationint?<0, 255>Highest acceptable saturation. Default value: atl::NIL.
inMinBrightnessfloat?<0.0f, INF>128.0fLowest acceptable brightness. Default value: 128.0f.
inMaxBrightnessfloat?<0.0f, INF>Highest acceptable brightness. Default value: atl::NIL.
inMinAmountfloat<0.0f, 1.0f>0.5fLowest acceptable fraction of pixels meeting the criteria. Default value: 0.5f.
inMaxAmountfloat<0.0f, 1.0f>1.0fHighest acceptable fraction of pixels meeting the criteria. Default value: 1.0f.
outIsPresentboolFlag indicating whether the object is present or not.
outAmountfloatFraction of pixels meeting the criteria.
outForegroundAvlNet.RegionRegion of pixels meeting the criteria.
outAlignedRoiAvlNet.ShapeRegionInput ROI after transformation (in the image coordinates).
diagHsxImageAvlNet.ImageImage represented in chosen color model.

Description

The filter extracts foreground pixels by means of image thresholding and checks if their number comparing to the area of the whole ROI fits the range (inMinAmount, inMaxAmount). If the input image has 3 channels, the ThresholdToRegion_HSx filter is used for thresholding, and if the image has 1 channel (i.e. it is monochromatic), the simple ThresholdToRegion filter is performed. In the latter case only inMinBrightness and inMaxBrightness parameters matter.

Examples

CheckPresence_PixelAmount performed on sample image with inMinAmount = 0.7. The defects are present in red circles.

Errors

List of possible exceptions:

Error type Description
DomainError Incorrect inMaxBrightness value in CheckPresence_PixelAmount.
DomainError Incorrect inMinBrightness value in CheckPresence_PixelAmount.
DomainError Region exceeds an input image in CheckPresence_PixelAmount.
DomainError Not supported inImage pixel format in CheckPresence_PixelAmount. Supported formats: 3xUInt8, 1xUInt8, 1xInt8, 1xUInt16, 1xInt16, 1xInt32, 1xReal.

Function Overrides

See also