Package com.irurueta.geometry.estimators

Class RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator

java.lang.Object

com.irurueta.geometry.estimators.ProjectiveTransformation2DRobustEstimator

com.irurueta.geometry.estimators.PointCorrespondenceProjectiveTransformation2DRobustEstimator

com.irurueta.geometry.estimators.RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator

public class RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator
extends PointCorrespondenceProjectiveTransformation2DRobustEstimator

Finds the best projective 2D transformation for provided collections of matched 2D points using RANSAC algorithm.

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	computeAndKeepInliers	Indicates whether inliers must be computed and kept.
private boolean	computeAndKeepResiduals	Indicates whether residuals must be computed and kept.
static final boolean	DEFAULT_COMPUTE_AND_KEEP_INLIERS	Indicates that by default inliers will only be computed but not kept.
static final boolean	DEFAULT_COMPUTE_AND_KEEP_RESIDUALS	Indicates that by default residuals will only be computed but not kept.
static final double	DEFAULT_THRESHOLD	Constant defining default threshold to determine whether points are inliers or not.
static final double	MIN_THRESHOLD	Minimum value that can be set as threshold.
private double	threshold	Threshold to determine whether points are inliers or not when testing possible estimation solutions.

Fields inherited from class com.irurueta.geometry.estimators.PointCorrespondenceProjectiveTransformation2DRobustEstimator

DEFAULT_ROBUST_METHOD, inputPoints, outputPoints

Fields inherited from class com.irurueta.geometry.estimators.ProjectiveTransformation2DRobustEstimator

confidence, covariance, DEFAULT_CONFIDENCE, DEFAULT_KEEP_COVARIANCE, DEFAULT_MAX_ITERATIONS, DEFAULT_PROGRESS_DELTA, DEFAULT_REFINE_RESULT, inliersData, keepCovariance, listener, locked, MAX_CONFIDENCE, MAX_PROGRESS_DELTA, maxIterations, MIN_CONFIDENCE, MIN_ITERATIONS, MIN_PROGRESS_DELTA, MINIMUM_SIZE, progressDelta, refineResult

Constructor Summary

Constructors

Constructor	Description
RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator()	Constructor.
RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator(ProjectiveTransformation2DRobustEstimatorListener listener)	Constructor.
RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator(ProjectiveTransformation2DRobustEstimatorListener listener, List<Point2D> inputPoints, List<Point2D> outputPoints)	Constructor with listener and lists of points to be used to estimate a projective 2D transformation.
RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator(List<Point2D> inputPoints, List<Point2D> outputPoints)	Constructor with lists of points to be used to estimate a projective 2D transformation.

Method Summary

Modifier and Type	Method	Description
ProjectiveTransformation2D	estimate()	Estimates a projective 2D transformation using a robust estimator and the best set of matched 2D point correspondences found using the robust estimator
com.irurueta.numerical.robust.RobustEstimatorMethod	getMethod()	Returns method being used for robust estimation.
protected double	getRefinementStandardDeviation()	Gets standard deviation used for Levenberg-Marquardt fitting during refinement.
double	getThreshold()	Returns threshold to determine whether points are inliers or not when testing possible estimation solutions.
boolean	isComputeAndKeepInliersEnabled()	Indicates whether inliers must be computed and kept.
boolean	isComputeAndKeepResidualsEnabled()	Indicates whether residuals must be computed and kept.
void	setComputeAndKeepInliersEnabled(boolean computeAndKeepInliers)	Specifies whether inliers must be computed and kept.
void	setComputeAndKeepResidualsEnabled(boolean computeAndKeepResiduals)	Specifies whether residuals must be computed and kept.
void	setThreshold(double threshold)	Sets threshold to determine whether points are inliers or not when testing possible estimation solutions.

Methods inherited from class com.irurueta.geometry.estimators.PointCorrespondenceProjectiveTransformation2DRobustEstimator

attemptRefine, create, create, create, create, create, create, create, create, create, create, create, create, create, create, create, create, getInputPoints, getOutputPoints, getQualityScores, isReady, setPoints, setQualityScores

Methods inherited from class com.irurueta.geometry.estimators.ProjectiveTransformation2DRobustEstimator

createFromLines, createFromLines, createFromLines, createFromLines, createFromLines, createFromLines, createFromLines, createFromLines, createFromPoints, createFromPoints, createFromPoints, createFromPoints, createFromPoints, createFromPoints, createFromPoints, createFromPoints, getConfidence, getCovariance, getInliersData, getListener, getMaxIterations, getProgressDelta, isCovarianceKept, isListenerAvailable, isLocked, isResultRefined, setConfidence, setCovarianceKept, setListener, setMaxIterations, setProgressDelta, setResultRefined

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_THRESHOLD

public static final double DEFAULT_THRESHOLD

Constant defining default threshold to determine whether points are inliers or not. By default, 1.0 is considered a good value for cases where measures are done on pixels, since typically the minimum resolution is 1 pixel.

See Also:

• Constant Field Values

MIN_THRESHOLD

public static final double MIN_THRESHOLD

Minimum value that can be set as threshold. Threshold must be strictly greater than 0.0.

See Also:

• Constant Field Values

DEFAULT_COMPUTE_AND_KEEP_INLIERS

public static final boolean DEFAULT_COMPUTE_AND_KEEP_INLIERS

Indicates that by default inliers will only be computed but not kept.

See Also:

• Constant Field Values

DEFAULT_COMPUTE_AND_KEEP_RESIDUALS

public static final boolean DEFAULT_COMPUTE_AND_KEEP_RESIDUALS

Indicates that by default residuals will only be computed but not kept.

See Also:

• Constant Field Values

threshold

private double threshold

Threshold to determine whether points are inliers or not when testing possible estimation solutions. The threshold refers to the amount of error (i.e. distance) a possible solution has on a matched pair of points.

computeAndKeepInliers

private boolean computeAndKeepInliers

Indicates whether inliers must be computed and kept.

computeAndKeepResiduals

private boolean computeAndKeepResiduals

Indicates whether residuals must be computed and kept.

Constructor Details

RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator

public RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator()

Constructor.

RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator

public RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator(List<Point2D> inputPoints,
 List<Point2D> outputPoints)

Constructor with lists of points to be used to estimate a projective 2D transformation. Points in the list located at the same position are considered to be matched. Hence, both lists must have the same size, and their size must be greater or equal than MINIMUM_SIZE.

Parameters:

inputPoints - list of input points to be used to estimate a projective 2D transformation.

outputPoints - list of output points to be used to estimate a projective 2D transformation.

Throws:

IllegalArgumentException - if provided lists of points don't have the same size or their size is smaller than MINIMUM_SIZE.

RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator

public RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator(ProjectiveTransformation2DRobustEstimatorListener listener)

Constructor.

Parameters:

listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator

public RANSACPointCorrespondenceProjectiveTransformation2DRobustEstimator(ProjectiveTransformation2DRobustEstimatorListener listener,
 List<Point2D> inputPoints,
 List<Point2D> outputPoints)

Constructor with listener and lists of points to be used to estimate a projective 2D transformation. Points in the list located at the same position are considered to be matched. Hence, both lists must have the same size, and their size must be greater or equal than MINIMUM_SIZE.

Parameters:

listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

inputPoints - list of input points to be used to estimate a projective 2D transformation.

outputPoints - list of output points to be used to estimate a projective 2D transformation.

Throws:

IllegalArgumentException - if provided lists of points don't have the same size or their size is smaller than MINIMUM_SIZE.

Method Details

getThreshold

public double getThreshold()

Returns threshold to determine whether points are inliers or not when testing possible estimation solutions. The threshold refers to the amount of error (i.e. Euclidean distance) a possible solution has on a matched pair of points.

Returns:

threshold to determine whether points are inliers or not when testing possible estimation solutions.

setThreshold

public void setThreshold(double threshold)
                  throws LockedException

Sets threshold to determine whether points are inliers or not when testing possible estimation solutions. The threshold refers to the amount of error (i.e. Euclidean distance) a possible solution has on a matched pair of points.

Parameters:

threshold - threshold to be set.

Throws:

IllegalArgumentException - if provided value is equal or less than zero.

LockedException - if robust estimator is locked because an estimation is already in progress.

isComputeAndKeepInliersEnabled

public boolean isComputeAndKeepInliersEnabled()

Indicates whether inliers must be computed and kept.

Returns:

true if inliers must be computed and kept, false if inliers only need to be computed but not kept.

setComputeAndKeepInliersEnabled

public void setComputeAndKeepInliersEnabled(boolean computeAndKeepInliers)
                                     throws LockedException

Specifies whether inliers must be computed and kept.

Parameters:

computeAndKeepInliers - true if inliers must be computed and kept, false if inliers only need to be computed but not kept.

Throws:

LockedException - if estimator is locked.

isComputeAndKeepResidualsEnabled

public boolean isComputeAndKeepResidualsEnabled()

Indicates whether residuals must be computed and kept.

Returns:

true if residuals must be computed and kept, false if residuals only need to be computed but not kept.

setComputeAndKeepResidualsEnabled

public void setComputeAndKeepResidualsEnabled(boolean computeAndKeepResiduals)
                                       throws LockedException

Specifies whether residuals must be computed and kept.

Parameters:

computeAndKeepResiduals - true if residuals must be computed and kept, false if residuals only need to be computed but not kept.

Throws:

LockedException - if estimator is locked.

estimate

public ProjectiveTransformation2D estimate()
                                    throws LockedException,
NotReadyException,
com.irurueta.numerical.robust.RobustEstimatorException

Estimates a projective 2D transformation using a robust estimator and the best set of matched 2D point correspondences found using the robust estimator

Specified by:

estimate in class ProjectiveTransformation2DRobustEstimator

Returns:

a projective 2D transformation

Throws:

LockedException - if robust estimator is locked because an estimation is already in progress

NotReadyException - if provided input data is not enough to start the estimation

com.irurueta.numerical.robust.RobustEstimatorException - if estimation fails for any reason (i.e. numerical instability, no solution available, etc)

getMethod

public com.irurueta.numerical.robust.RobustEstimatorMethod getMethod()

Returns method being used for robust estimation.

Specified by:

getMethod in class ProjectiveTransformation2DRobustEstimator

Returns:

method being used for robust estimation.

getRefinementStandardDeviation

protected double getRefinementStandardDeviation()

Gets standard deviation used for Levenberg-Marquardt fitting during refinement. Returned value gives an indication of how much variance each residual has. Typically, this value is related to the threshold used on each robust estimation, since residuals of found inliers are within the range of such threshold.

Specified by:

getRefinementStandardDeviation in class ProjectiveTransformation2DRobustEstimator

Returns:

standard deviation used for refinement.