CalibrationLineScan Class Reference

Collection of calibration line scan functions. More...

Static Public Member Functions
static Point2Dd[]	CalculateTwoPointsForCalibrationOfMovement (ImagePlane imagePlane, Area2D aoi, CalibrationPatternContrast contrast, int minContrast, ValueRange< double > pointSizeRange, ScanDirection scanDirection)
	Extracts two points which can be used for the calibration of the movement of line scan cameras. More...
static EdgeDetectionResult	DetectEdgesOfStripeTarget (Image imageStripes, Area2D aoi, int numStripes, ScanDirection scanDirection, double threshold)
	This function detects edges from a calibration pattern with alternating black and white stripes. More...
static LineScanCalibrator	CreateLineScanCalibration (Point2Dd calibrationPoint1, Point2Dd calibrationPoint2, double referenceDistanceCalibrationPoints, EdgeDetectionResult edgeDetectionResult, double referenceWidthStripes, LineScanCalibrationConfiguration configuration)
	This function calibrates linescan cameras. More...

Detailed Description

Collection of calibration line scan functions.

Member Function Documentation

CalculateTwoPointsForCalibrationOfMovement()

static Point2Dd[] CalculateTwoPointsForCalibrationOfMovement ( ImagePlane  imagePlane, Area2D  aoi, CalibrationPatternContrast  contrast, int  minContrast, ValueRange< double >  pointSizeRange, ScanDirection  scanDirection  )

static

Extracts two points which can be used for the calibration of the movement of line scan cameras.

Parameters

imagePlane	An image plane containing the calibration points.
aoi	Area of interest where the calibration points can be found
contrast	Selects whether the image shows white on black or black on white dots.
minContrast	Minimum gray value contrast between the object and the background of the calibration points. Value to be set depends on the quality of the image taken.
pointSizeRange	Desired range of the point size (in number of pixels).
scanDirection	Scan direction of the camera.

Returns

CreateLineScanCalibration()

static LineScanCalibrator CreateLineScanCalibration ( Point2Dd  calibrationPoint1, Point2Dd  calibrationPoint2, double  referenceDistanceCalibrationPoints, EdgeDetectionResult  edgeDetectionResult, double  referenceWidthStripes, LineScanCalibrationConfiguration  configuration  )

static

This function calibrates linescan cameras.

The Transformation result includes a 3rd order polynom for the line calibration and a factor to correct the movement direction. Note, that x and y do not depend on each other. All mixed coefficients are zero.

For the calibration of the movement direction an image containing two calibration dots is needed. The pixel coordinates of the dots calibrationPoint1 and calibrationPoint2 are calculated by the function CalculateTwoPointsForCalibrationOfMovement(ImagePlane, Area2D, CalibrationPatternContrast, int, ValueRange<double>, ScanDirection). CreateLineScanCalibration needs the coordinates and the reference distance between the dots referenceDistanceCalibrationPoints .

For the linescan calibration an image of a pattern with alternating black and white stripes has to be aquired. Also, the width of the stripes referenceWidthStripes has to be given as reference. Function DetectEdgesOfStripeTarget(Image, Area2D, int, ScanDirection, double) detects the stripes of the calibration pattern and gives their indices ScanLineIndices and EdgeIndices in edgeDetectionResult .

Parameters

calibrationPoint1	First calibration point (left or top).
calibrationPoint2	Second calibration point (right or bottom).
referenceDistanceCalibrationPoints	Reference distance between the two calibration points (same units as referenceWidthStripes ).
edgeDetectionResult	Containing the ScanLineIndices and EdgeIndices.
referenceWidthStripes	Reference width of stripes in calibration pattern ImageStripes.
configuration	Configuration of the linescan calibration.

Returns

A line scan calibrator including a transformation and its quality.

DetectEdgesOfStripeTarget()

static EdgeDetectionResult DetectEdgesOfStripeTarget ( Image  imageStripes, Area2D  aoi, int  numStripes, ScanDirection  scanDirection, double  threshold  )

static

This function detects edges from a calibration pattern with alternating black and white stripes.

Parameters

imageStripes	Calibration pattern with alternating black and white stripes.
aoi	Area of interest in the given image.
numStripes	Number of stripes in the calibration pattern.
scanDirection	Scan direction of the camera.
threshold	Threshold for edge detection in the given image (pixel data type dependent, see also See also Edge.FindAll(ImagePlane, EdgeSearchMode, EdgeType, double) ).

Returns

Result of the edge detection. The output of this function is used by function CreateLineScanCalibration calculating the line scan calibration. For the detection of the transition between stripes, the CVB function

See also

Edge.FindAll(ImagePlane, EdgeSearchMode, EdgeType, double)

is used. For further information see the documentation of the CVB edge tool.