boofcv.alg.feature.detect.grid

Class DetectSquareCalibrationPoints

java.lang.Object

boofcv.alg.feature.detect.grid.DetectSquareCalibrationPoints

public class DetectSquareCalibrationPoints
extends java.lang.Object

Detects square grid calibration targets from binary images. The output is a set of ordered calibration points with the number of rows and columns. Calibration points are in a row-major ordering. Processing steps:

1. Morphological noise reduction
2. Create blob clusters
3. Detect rectangles
4. Order rectangles and extract calibration points.

See comments inside of code for how false positive blobs are removed. Rotational orientation is not ensured and for some applications the orientation might need to be adjusted.

Constructor Summary

Constructors

Constructor and Description
DetectSquareCalibrationPoints(double relativeSizeThreshold, double spaceToSquareRatio, int gridCols, int gridRows)

Method Summary

Methods

Modifier and Type	Method and Description
java.util.List<QuadBlob>	getAllSquares()
boofcv.struct.image.ImageSInt32	getBlobs()
DetectQuadBlobsBinary	getDetectBlobs()
java.lang.String	getErrorMessage()
java.util.List<georegression.struct.point.Point2D_F64>	getInterestPoints()
java.util.List<QuadBlob>	getInterestSquares()
int	getNumberOfLabels()
java.util.List<QuadBlob>	getSquaresBad()
java.util.List<georegression.struct.point.Point2D_F64>	getTargetQuadrilateral() Returns corner points in quadrilateral that bounds all the target points, approximately.
boolean	process(boofcv.struct.image.ImageUInt8 thresholded) Processes the image and detects calibration targets.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DetectSquareCalibrationPoints

public DetectSquareCalibrationPoints(double relativeSizeThreshold,
                             double spaceToSquareRatio,
                             int gridCols,
                             int gridRows)

Parameters:

relativeSizeThreshold - Increases or decreases the minimum allowed blob size. Try 1.0

spaceToSquareRatio - length of the space relative to the length of a square in the grid

gridCols - Number of squares wide the grid is. Target dependent.

gridRows - Number of squares tall the grid is. Target dependent.

Method Detail

process

public boolean process(boofcv.struct.image.ImageUInt8 thresholded)

Processes the image and detects calibration targets. If one is found then true is returned and calibration points are extracted.

Parameters:

thresholded - Binary image where potential grid squares are set to one.

Returns:

True if it was successful and false otherwise. If false call getMessage() for details.

getTargetQuadrilateral

public java.util.List<georegression.struct.point.Point2D_F64> getTargetQuadrilateral()

Returns corner points in quadrilateral that bounds all the target points, approximately.

getBlobs

public boofcv.struct.image.ImageSInt32 getBlobs()

getErrorMessage

public java.lang.String getErrorMessage()

getAllSquares

public java.util.List<QuadBlob> getAllSquares()

getInterestSquares

public java.util.List<QuadBlob> getInterestSquares()

getInterestPoints

public java.util.List<georegression.struct.point.Point2D_F64> getInterestPoints()

getSquaresBad

public java.util.List<QuadBlob> getSquaresBad()

getNumberOfLabels

public int getNumberOfLabels()

getDetectBlobs

public DetectQuadBlobsBinary getDetectBlobs()