Package com.irurueta.ar.epipolar.estimators

Class LMedSFundamentalMatrixRobustEstimator

java.lang.Object
com.irurueta.ar.epipolar.estimators.FundamentalMatrixRobustEstimator
com.irurueta.ar.epipolar.estimators.LMedSFundamentalMatrixRobustEstimator
public class LMedSFundamentalMatrixRobustEstimator extends FundamentalMatrixRobustEstimator
Finds the best fundamental matrix for provided collections of matched 2D points using LMedS algorithm.

  • Field Details

    • DEFAULT_STOP_THRESHOLD

      public static final double DEFAULT_STOP_THRESHOLD
      Default value to be used for stop threshold. Stop threshold can be used to keep the algorithm iterating in case that best estimated threshold using median of residuals is not small enough. Once a solution is found that generates a threshold below this value, the algorithm will stop. The stop threshold can be used to prevent the LMedS algorithm iterating too many times in cases where samples have a very similar accuracy. For instance, in cases where proportion of outliers is very small (close to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would iterate for a long time trying to find the best solution when indeed there is no need to do that if a reasonable threshold has already been reached. Because of this behaviour the stop threshold can be set to a value much lower than the one typically used in RANSAC, and yet the algorithm could still produce even smaller thresholds in estimated results.
      See Also:

    • MIN_STOP_THRESHOLD

      public static final double MIN_STOP_THRESHOLD
      Minimum allowed stop threshold value.
      See Also:

    • stopThreshold

      private double stopThreshold
      Threshold to be used to keep the algorithm iterating in case that best estimated threshold using median of residuals is not small enough. Once a solution is found that generates a threshold below this value, the algorithm will stop. The stop threshold can be used to prevent the LMedS algorithm iterating too many times in cases where samples have a very similar accuracy. For instance, in cases where proportion of outliers is very small (close to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would iterate for a long time trying to find the best solution when indeed there is no need to do that if a reasonable threshold has already been reached. Because of this behaviour the stop threshold can be set to a value much lower than the one typically used in RANSAC, and yet the algorithm could still produce even smaller thresholds in estimated results.

  • Constructor Details

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(FundamentalMatrixEstimatorMethod fundMatrixEstimatorMethod)
      Constructor.
      Parameters:
      fundMatrixEstimatorMethod - method for non-robust fundamental matrix estimator.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(FundamentalMatrixEstimatorMethod fundMatrixEstimatorMethod, FundamentalMatrixRobustEstimatorListener listener)
      Constructor.
      Parameters:
      fundMatrixEstimatorMethod - method for non-robust fundamental matrix estimator.
      listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(FundamentalMatrixEstimatorMethod fundMatrixEstimatorMethod, List<com.irurueta.geometry.Point2D> leftPoints, List<com.irurueta.geometry.Point2D> rightPoints)
      Constructor.
      Parameters:
      fundMatrixEstimatorMethod - method for non-robust fundamental matrix estimator.
      leftPoints - 2D points on left view.
      rightPoints - 2D points on right view.
      Throws:
      IllegalArgumentException - if provided list of points do not have the same length or their length is less than 7 points.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(FundamentalMatrixEstimatorMethod fundMatrixEstimatorMethod, List<com.irurueta.geometry.Point2D> leftPoints, List<com.irurueta.geometry.Point2D> rightPoints, FundamentalMatrixRobustEstimatorListener listener)
      Constructor.
      Parameters:
      fundMatrixEstimatorMethod - method for non-robust fundamental matrix estimator.
      leftPoints - 2D points on left view.
      rightPoints - 2D points on right view.
      listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.
      Throws:
      IllegalArgumentException - if provided list of points do not have the same length or their length is less than 7 points.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator()
      Constructor.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(FundamentalMatrixRobustEstimatorListener listener)
      Constructor.
      Parameters:
      listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(List<com.irurueta.geometry.Point2D> leftPoints, List<com.irurueta.geometry.Point2D> rightPoints)
      Constructor.
      Parameters:
      leftPoints - 2D points on left view.
      rightPoints - 2D points on right view.
      Throws:
      IllegalArgumentException - if provided list of points do not have the same length or their length is less than 7 points.

    • LMedSFundamentalMatrixRobustEstimator

      public LMedSFundamentalMatrixRobustEstimator(List<com.irurueta.geometry.Point2D> leftPoints, List<com.irurueta.geometry.Point2D> rightPoints, FundamentalMatrixRobustEstimatorListener listener)
      Constructor.
      Parameters:
      leftPoints - 2D points on left view.
      rightPoints - 2D points on right view.
      listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.
      Throws:
      IllegalArgumentException - if provided list of points do not have the same length or their length is less than 7 points.

  • Method Details

    • getStopThreshold

      public double getStopThreshold()
      Returns threshold to be used to keep the algorithm iterating in case that best estimated threshold using median of residuals is not small enough. Once a solution is found that generates a threshold below this value, the algorithm will stop. The stop threshold can be used to prevent the LMedS algorithm iterating too many times in cases where samples have a very similar accuracy. For instance, in cases where proportion of outliers is very small (close to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would iterate for a long time trying to find the best solution when indeed there is no need to do that if a reasonable threshold has already been reached. Because of this behaviour the stop threshold can be set to a value much lower than the one typically used in RANSAC, and yet the algorithm could still produce even smaller thresholds in estimated results.
      Returns:
      stop threshold to stop the algorithm prematurely when a certain accuracy has been reached.

    • setStopThreshold

      public void setStopThreshold(double stopThreshold) throws com.irurueta.geometry.estimators.LockedException
      Sets threshold to be used to keep the algorithm iterating in case that best estimated threshold using median of residuals is not small enough. Once a solution is found that generates a threshold below this value, the algorithm will stop. The stop threshold can be used to prevent the LMedS algorithm iterating too many times in cases where samples have a very similar accuracy. For instance, in cases where proportion of outliers is very small (close to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would iterate for a long time trying to find the best solution when indeed there is no need to do that if a reasonable threshold has already been reached. Because of this behaviour the stop threshold can be set to a value much lower than the one typically used in RANSAC, and yet the algorithm could still produce even smaller thresholds in estimated results.
      Parameters:
      stopThreshold - stop threshold to stop the algorithm prematurely when a certain accuracy has been reached.
      Throws:
      IllegalArgumentException - if provided value is zero or negative.
      com.irurueta.geometry.estimators.LockedException - if robust estimator is locked because an estimation is already in progress.

    • estimate

      public FundamentalMatrix estimate() throws com.irurueta.geometry.estimators.LockedException, com.irurueta.geometry.estimators.NotReadyException, com.irurueta.numerical.robust.RobustEstimatorException
      Estimates a radial distortion using a robust estimator and the best set of matched 2D points found using the robust estimator.
      Specified by:
      estimate in class FundamentalMatrixRobustEstimator
      Returns:
      a radial distortion.
      Throws:
      com.irurueta.geometry.estimators.LockedException - if robust estimator is locked because an estimation is already in progress.
      com.irurueta.geometry.estimators.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 FundamentalMatrixRobustEstimator
      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 FundamentalMatrixRobustEstimator
      Returns:
      standard deviation used for refinement.