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1   /*
2    * Copyright (C) 2017 Alberto Irurueta Carro (alberto@irurueta.com)
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *         http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package com.irurueta.geometry.estimators;
17  
18  import com.irurueta.algebra.Matrix;
19  import com.irurueta.geometry.MetricTransformation2D;
20  import com.irurueta.geometry.Point2D;
21  import com.irurueta.geometry.refiners.MetricTransformation2DRefiner;
22  import com.irurueta.numerical.robust.InliersData;
23  import com.irurueta.numerical.robust.RobustEstimatorException;
24  import com.irurueta.numerical.robust.RobustEstimatorMethod;
25  
26  import java.util.List;
27  
28  /**
29   * This is an abstract class to robustly find the best metric transformation
30   * for collections of matching 2D points.
31   * Implementations of this class should be able to detect and discard outliers
32   * in order to find the best solution.
33   */
34  @SuppressWarnings("DuplicatedCode")
35  public abstract class MetricTransformation2DRobustEstimator {
36  
37      /**
38       * Minimum number of matched points required to estimate a metric 2D
39       * transformation.
40       */
41      public static final int MINIMUM_SIZE = MetricTransformation2DEstimator.MINIMUM_SIZE;
42  
43      /**
44       * For some point configurations a solution can be found with only 2 points.
45       */
46      public static final int WEAK_MINIMUM_SIZE = MetricTransformation2DEstimator.WEAK_MINIMUM_SIZE;
47  
48      /**
49       * Default amount of progress variation before notifying a change in
50       * estimation progress. By default, this is set to 5%.
51       */
52      public static final float DEFAULT_PROGRESS_DELTA = 0.05f;
53  
54      /**
55       * Minimum allowed value for progress delta.
56       */
57      public static final float MIN_PROGRESS_DELTA = 0.0f;
58  
59      /**
60       * Maximum allowed value for progress delta.
61       */
62      public static final float MAX_PROGRESS_DELTA = 1.0f;
63  
64      /**
65       * Constant defining default confidence of the estimated result, which is
66       * 99%. This means that with a probability of 99% estimation will be
67       * accurate because chosen sub-samples will be inliers.
68       */
69      public static final double DEFAULT_CONFIDENCE = 0.99;
70  
71      /**
72       * Default maximum allowed number of iterations.
73       */
74      public static final int DEFAULT_MAX_ITERATIONS = 5000;
75  
76      /**
77       * Minimum allowed confidence value.
78       */
79      public static final double MIN_CONFIDENCE = 0.0;
80  
81      /**
82       * Maximum allowed confidence value.
83       */
84      public static final double MAX_CONFIDENCE = 1.0;
85  
86      /**
87       * Minimum allowed number of iterations.
88       */
89      public static final int MIN_ITERATIONS = 1;
90  
91      /**
92       * Indicates that is refined by default using Levenberg-Marquardt
93       * fitting algorithm over found inliers.
94       */
95      public static final boolean DEFAULT_REFINE_RESULT = true;
96  
97      /**
98       * Indicates that covariance is not kept by default after refining result.
99       */
100     public static final boolean DEFAULT_KEEP_COVARIANCE = false;
101 
102     /**
103      * Default robust estimator method when none is provided.
104      */
105     public static final RobustEstimatorMethod DEFAULT_ROBUST_METHOD = RobustEstimatorMethod.PROMEDS;
106 
107     /**
108      * Listener to be notified of events such as when estimation starts, ends
109      * or its progress significantly changes.
110      */
111     protected MetricTransformation2DRobustEstimatorListener listener;
112 
113     /**
114      * Indicates if this estimator is locked because an estimation is being
115      * computed.
116      */
117     protected boolean locked;
118 
119     /**
120      * Amount of progress variation before notifying a progress change during
121      * estimation.
122      */
123     protected float progressDelta;
124 
125     /**
126      * Amount of confidence expressed as a value between 0.0 and 1.0 (which is
127      * equivalent to 100%). The amount of confidence indicates the probability
128      * that the estimated result is correct. Usually this value will be close
129      * to 1.0, but not exactly 1.0.
130      */
131     protected double confidence;
132 
133     /**
134      * Maximum allowed number of iterations. When the maximum number of
135      * iterations is exceeded, result will not be available, however an
136      * approximate result will be available for retrieval.
137      */
138     protected int maxIterations;
139 
140     /**
141      * Data related to inliers found after estimation.
142      */
143     protected InliersData inliersData;
144 
145     /**
146      * Indicates whether result must be refined using Levenberg-Marquardt
147      * fitting algorithm over found inliers.
148      * If true, inliers will be computed and kept in any implementation
149      * regardless of the settings.
150      */
151     protected boolean refineResult;
152 
153     /**
154      * Indicates whether covariance must be kept after refining result.
155      * This setting is only taken into account if result is refined.
156      */
157     private boolean keepCovariance;
158 
159     /**
160      * Estimated covariance of estimated 2D Euclidean transformation.
161      * This is only available when result has been refined and covariance is
162      * kept.
163      */
164     private Matrix covariance;
165 
166     /**
167      * List of points to be used to estimate a metric 3D transformation.
168      * Each point in the list of input points must be matched with the
169      * corresponding point in the list of output points located at the same
170      * position. Hence, both input points and output points must have the same
171      * size, and their size must be greater or equal than MINIMUM_SIZE.
172      */
173     protected List<Point2D> inputPoints;
174 
175     /**
176      * List of points to be used to estimate a metric 2D transformation.
177      * Each point in the lis tof output points must be matched with the
178      * corresponding point in the list of input points located at the same
179      * position. Hence, both input points and output points must have the same
180      * size, and their size must be greater or equal than MINIMUM_SIZE.
181      */
182     protected List<Point2D> outputPoints;
183 
184     /**
185      * Indicates whether estimation can start with only 2 points or not.
186      * True allows 2 points, false requires 3.
187      */
188     private boolean weakMinimumSizeAllowed;
189 
190     /**
191      * Constructor.
192      */
193     protected MetricTransformation2DRobustEstimator() {
194         progressDelta = DEFAULT_PROGRESS_DELTA;
195         confidence = DEFAULT_CONFIDENCE;
196         maxIterations = DEFAULT_MAX_ITERATIONS;
197         refineResult = DEFAULT_REFINE_RESULT;
198         keepCovariance = DEFAULT_KEEP_COVARIANCE;
199     }
200 
201     /**
202      * Constructor.
203      *
204      * @param listener listener to be notified of events such as when estimation
205      *                 starts, ends or its progress significantly changes.
206      */
207     protected MetricTransformation2DRobustEstimator(final MetricTransformation2DRobustEstimatorListener listener) {
208         this();
209         this.listener = listener;
210     }
211 
212     /**
213      * Constructor with lists of points to be used to estimate a metric 2D
214      * transformation.
215      * Points in the list located at the same position are considered to be
216      * matched. Hence, both lists must have the same size, and their size must
217      * be greater or equal than MINIMUM_SIZE.
218      *
219      * @param inputPoints  list of input points to be used to estimate a
220      *                     metric 2D transformation.
221      * @param outputPoints list of output points to be used to estimate a
222      *                     metric 2D transformation.
223      * @throws IllegalArgumentException if provided lists of points don't have
224      *                                  the same size or their size is smaller than MINIMUM_SIZE.
225      */
226     protected MetricTransformation2DRobustEstimator(final List<Point2D> inputPoints, final List<Point2D> outputPoints) {
227         this();
228         internalSetPoints(inputPoints, outputPoints);
229     }
230 
231     /**
232      * Constructor with listener and lists of points to be used to estimate a
233      * metric 2D transformation.
234      * Points in the list located at the same position are considered to be
235      * matched. Hence, both lists must have the same size, and their size must
236      * be greater or equal than MINIMUM_SIZE.
237      *
238      * @param listener     listener to be notified of events such as when estimation
239      *                     starts, ends or its progress significantly changes.
240      * @param inputPoints  list of input points to be used to estimate a
241      *                     metric 2D transformation.
242      * @param outputPoints list of output points to be used to estimate a
243      *                     metric 2D transformation.
244      * @throws IllegalArgumentException if provided lists of points don't have
245      *                                  the same size or their size is smaller than MINIMUM_SIZE.
246      */
247     protected MetricTransformation2DRobustEstimator(
248             final MetricTransformation2DRobustEstimatorListener listener,
249             final List<Point2D> inputPoints, final List<Point2D> outputPoints) {
250         this(listener);
251         internalSetPoints(inputPoints, outputPoints);
252     }
253 
254     /**
255      * Constructor.
256      *
257      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
258      */
259     protected MetricTransformation2DRobustEstimator(final boolean weakMinimumSizeAllowed) {
260         this();
261         this.weakMinimumSizeAllowed = weakMinimumSizeAllowed;
262     }
263 
264     /**
265      * Constructor.
266      *
267      * @param listener               listener to be notified of events such as when estimation
268      *                               starts, ends or its progress significantly changes.
269      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
270      */
271     protected MetricTransformation2DRobustEstimator(
272             final MetricTransformation2DRobustEstimatorListener listener, final boolean weakMinimumSizeAllowed) {
273         this();
274         this.listener = listener;
275         this.weakMinimumSizeAllowed = weakMinimumSizeAllowed;
276     }
277 
278     /**
279      * Constructor with lists of points to be used to estimate a metric 2D
280      * transformation.
281      * Points in the list located at the same position are considered to be
282      * matched. Hence, both lists must have the same size, and their size must
283      * be greater or equal than MINIMUM_SIZE.
284      *
285      * @param inputPoints            list of input points to be used to estimate a
286      *                               metric 2D transformation.
287      * @param outputPoints           list of output points to be used to estimate a
288      *                               metric 2D transformation.
289      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
290      * @throws IllegalArgumentException if provided lists of points don't have
291      *                                  the same size or their size is smaller than MINIMUM_SIZE.
292      */
293     protected MetricTransformation2DRobustEstimator(
294             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final boolean weakMinimumSizeAllowed) {
295         this();
296         this.weakMinimumSizeAllowed = weakMinimumSizeAllowed;
297         internalSetPoints(inputPoints, outputPoints);
298     }
299 
300     /**
301      * Constructor with listener and lists of points to be used to estimate a
302      * metric 2D transformation.
303      * Points in the list located at the same position are considered to be
304      * matched. Hence, both lists must have the same size, and their size must
305      * be greater or equal than MINIMUM_SIZE.
306      *
307      * @param listener               listener to be notified of events such as when estimation
308      *                               starts, ends or its progress significantly changes.
309      * @param inputPoints            list of input points to be used to estimate a
310      *                               metric 2D transformation.
311      * @param outputPoints           list of output points to be used to estimate a
312      *                               metric 2D transformation.
313      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
314      * @throws IllegalArgumentException if provided lists of points don't have
315      *                                  the same size or their size is smaller than MINIMUM_SIZE.
316      */
317     protected MetricTransformation2DRobustEstimator(
318             final MetricTransformation2DRobustEstimatorListener listener,
319             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final boolean weakMinimumSizeAllowed) {
320         this(listener);
321         this.weakMinimumSizeAllowed = weakMinimumSizeAllowed;
322         internalSetPoints(inputPoints, outputPoints);
323     }
324 
325     /**
326      * Returns list of input points to be used to estimate a metric 2D
327      * transformation.
328      * Each point in the list of input points must be matched with the
329      * corresponding point in the list of output points located at the same
330      * position. Hence, both input points and output points must have the same
331      * size, and their size must be greater or equal than MINIMUM_SIZE.
332      *
333      * @return list of input points to be used to estimate a metric 2D
334      * transformation.
335      */
336     public List<Point2D> getInputPoints() {
337         return inputPoints;
338     }
339 
340     /**
341      * Returns list of output points to be used to estimate a metric 2D
342      * transformation.
343      * Each point in the list of output points must be matched with the
344      * corresponding point in the list of input points located at the same
345      * position. Hence, both input points and output points must have the same
346      * size, and their size must be greater or equal than MINIMUM_SIZE.
347      *
348      * @return list of output points to be used to estimate a metric 2D
349      * transformation.
350      */
351     public List<Point2D> getOutputPoints() {
352         return outputPoints;
353     }
354 
355     /**
356      * Sets list of points to be used to estimate a metric 2D
357      * transformation.
358      * Points in the list located at the same position are considered to be
359      * matched. Hence, both lists must have the same size, and their size must
360      * be greater or equal than MINIMUM_SIZE.
361      *
362      * @param inputPoints  list of input points to be used to estimate a
363      *                     metric 2D transformation.
364      * @param outputPoints list of output points to be used to estimate a
365      *                     metric 2D transformation.
366      * @throws IllegalArgumentException if provided lists of points don't have
367      *                                  the same size or their size is smaller than MINIMUM_SIZE.
368      * @throws LockedException          if estimator is locked because a computation is
369      *                                  already in progress.
370      */
371     public void setPoints(final List<Point2D> inputPoints, final List<Point2D> outputPoints) throws LockedException {
372         if (isLocked()) {
373             throw new LockedException();
374         }
375         internalSetPoints(inputPoints, outputPoints);
376     }
377 
378     /**
379      * Indicates if estimator is ready to start the metric 2D transformation
380      * estimation.
381      * This is true when input data (i.e. lists of matched points) are provided
382      * and a minimum of MINIMUM_SIZE points are available.
383      *
384      * @return true if estimator is ready, false otherwise.
385      */
386     public boolean isReady() {
387         return inputPoints != null && outputPoints != null && inputPoints.size() == outputPoints.size()
388                 && inputPoints.size() >= getMinimumPoints();
389     }
390 
391     /**
392      * Returns quality scores corresponding to each pair of matched points.
393      * The larger the score value the better the quality of the matching.
394      * This implementation always returns null.
395      * Subclasses using quality scores must implement proper behaviour.
396      *
397      * @return quality scores corresponding to each pair of matched points.
398      */
399     public double[] getQualityScores() {
400         return null;
401     }
402 
403     /**
404      * Sets quality scores corresponding to each pair of matched points.
405      * The larger the score value the better the quality of the matching.
406      * This implementation makes no action.
407      * Subclasses using quality scores must implement proper behaviour.
408      *
409      * @param qualityScores quality scores corresponding to each pair of matched
410      *                      points.
411      * @throws LockedException          if robust estimator is locked because an
412      *                                  estimation is already in progress.
413      * @throws IllegalArgumentException if provided quality scores length is
414      *                                  smaller than MINIMUM_SIZE (i.e. 3 samples).
415      */
416     public void setQualityScores(final double[] qualityScores) throws LockedException {
417     }
418 
419     /**
420      * Returns reference to listener to be notified of events such as when
421      * estimation starts, ends or its progress significantly changes.
422      *
423      * @return listener to be notified of events.
424      */
425     public MetricTransformation2DRobustEstimatorListener getListener() {
426         return listener;
427     }
428 
429     /**
430      * Sets listener to be notified of events such as when estimation starts,
431      * ends or its progress significantly changes.
432      *
433      * @param listener listener to be notified of events.
434      * @throws LockedException if robust estimator is locked.
435      */
436     public void setListener(final MetricTransformation2DRobustEstimatorListener listener) throws LockedException {
437         if (isLocked()) {
438             throw new LockedException();
439         }
440         this.listener = listener;
441     }
442 
443     /**
444      * Indicates whether listener has been provided and is available for
445      * retrieval.
446      *
447      * @return true if available, false otherwise.
448      */
449     public boolean isListenerAvailable() {
450         return listener != null;
451     }
452 
453     /**
454      * Indicates whether estimation can start with only 2 points or not.
455      *
456      * @return true allows 2 points, false requires 3.
457      */
458     public boolean isWeakMinimumSizeAllowed() {
459         return weakMinimumSizeAllowed;
460     }
461 
462     /**
463      * Specifies whether estimation can start with only 2 points or not.
464      *
465      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
466      * @throws LockedException if estimator is locked.
467      */
468     public void setWeakMinimumSizeAllowed(final boolean weakMinimumSizeAllowed) throws LockedException {
469         if (isLocked()) {
470             throw new LockedException();
471         }
472         this.weakMinimumSizeAllowed = weakMinimumSizeAllowed;
473     }
474 
475     /**
476      * Required minimum number of point correspondences to start the estimation.
477      * Can be either 2 or 3.
478      *
479      * @return minimum number of point correspondences.
480      */
481     public int getMinimumPoints() {
482         return weakMinimumSizeAllowed ? WEAK_MINIMUM_SIZE : MINIMUM_SIZE;
483     }
484 
485     /**
486      * Indicates if this instance is locked because estimation is being
487      * computed.
488      *
489      * @return true if locked, false otherwise.
490      */
491     public boolean isLocked() {
492         return locked;
493     }
494 
495     /**
496      * Returns amount of progress variation before notifying a progress change
497      * during estimation.
498      *
499      * @return amount of progress variation before notifying a progress change
500      * during estimation.
501      */
502     public float getProgressDelta() {
503         return progressDelta;
504     }
505 
506     /**
507      * Sets amount of progress variation before notifying a progress change
508      * during estimation.
509      *
510      * @param progressDelta amount of progress variation before notifying a
511      *                      progress change during estimation.
512      * @throws IllegalArgumentException if progress delta is less than zero or
513      *                                  greater than 1.
514      * @throws LockedException          if this estimator is locked because an estimation
515      *                                  is being computed.
516      */
517     public void setProgressDelta(final float progressDelta) throws LockedException {
518         if (isLocked()) {
519             throw new LockedException();
520         }
521         if (progressDelta < MIN_PROGRESS_DELTA || progressDelta > MAX_PROGRESS_DELTA) {
522             throw new IllegalArgumentException();
523         }
524         this.progressDelta = progressDelta;
525     }
526 
527     /**
528      * Returns amount of confidence expressed as a value between 0.0 and 1.0
529      * (which is equivalent to 100%). The amount of confidence indicates the
530      * probability that the estimated result is correct. Usually this value will
531      * be close to 1.0, but not exactly 1.0.
532      *
533      * @return amount of confidence as a value between 0.0 and 1.0.
534      */
535     public double getConfidence() {
536         return confidence;
537     }
538 
539     /**
540      * Sets amount of confidence expressed as a value between 0.0 and 1.0 (which
541      * is equivalent to 100%). The amount of confidence indicates the
542      * probability that the estimated result is correct. Usually this value will
543      * be close to 1.0, but not exactly 1.0.
544      *
545      * @param confidence confidence to be set as a value between 0.0 and 1.0.
546      * @throws IllegalArgumentException if provided value is not between 0.0 and
547      *                                  1.0.
548      * @throws LockedException          if this estimator is locked because an estimator
549      *                                  is being computed.
550      */
551     public void setConfidence(final double confidence) throws LockedException {
552         if (isLocked()) {
553             throw new LockedException();
554         }
555         if (confidence < MIN_CONFIDENCE || confidence > MAX_CONFIDENCE) {
556             throw new IllegalArgumentException();
557         }
558         this.confidence = confidence;
559     }
560 
561     /**
562      * Returns maximum allowed number of iterations. If maximum allowed number
563      * of iterations is achieved without converging to a result when calling
564      * estimate(), a RobustEstimatorException will be raised.
565      *
566      * @return maximum allowed number of iterations.
567      */
568     public int getMaxIterations() {
569         return maxIterations;
570     }
571 
572     /**
573      * Sets maximum allowed number of iterations. When the maximum number of
574      * iterations is exceeded, result will not be available, however an
575      * approximate result will be available for retrieval.
576      *
577      * @param maxIterations maximum allowed number of iterations to be set.
578      * @throws IllegalArgumentException if provided value is less than 1.
579      * @throws LockedException          if this estimator is locked because an estimation
580      *                                  is being computed.
581      */
582     public void setMaxIterations(final int maxIterations) throws LockedException {
583         if (isLocked()) {
584             throw new LockedException();
585         }
586         if (maxIterations < MIN_ITERATIONS) {
587             throw new IllegalArgumentException();
588         }
589         this.maxIterations = maxIterations;
590     }
591 
592     /**
593      * Gets data related to inliers found after estimation.
594      *
595      * @return data related to inliers found after estimation.
596      */
597     public InliersData getInliersData() {
598         return inliersData;
599     }
600 
601     /**
602      * Indicates whether result must be refined using Levenberg-Marquardt
603      * fitting algorithm over found inliers.
604      * If ture, inliers will be computed and kept in any implementation
605      * regardless of the settings.
606      *
607      * @return true to refine result, false to simply use result found by
608      * robust estimator without further refining.
609      */
610     public boolean isResultRefined() {
611         return refineResult;
612     }
613 
614     /**
615      * Specifies whether result must be refined using Levenberg-Marquardt
616      * fitting algorithm over found inliers.
617      *
618      * @param refineResult true to refine result, false to simply use result
619      *                     found by robust estimator without further refining.
620      * @throws LockedException if estimator is locked.
621      */
622     public void setResultRefined(final boolean refineResult) throws LockedException {
623         if (isLocked()) {
624             throw new LockedException();
625         }
626         this.refineResult = refineResult;
627     }
628 
629     /**
630      * Indicates whether covariance must be kept after refining result.
631      * This setting is only taken into account if result is refined.
632      *
633      * @return true if covariance must be kept after refining result, false
634      * otherwise.
635      */
636     public boolean isCovarianceKept() {
637         return keepCovariance;
638     }
639 
640     /**
641      * Specifies whether covariance must be kept after refining result.
642      * This setting is only taken into account if result is refined.
643      *
644      * @param keepCovariance true if covariance must be kept after refining
645      *                       result, false otherwise.
646      * @throws LockedException if estimator is locked.
647      */
648     public void setCovarianceKept(final boolean keepCovariance) throws LockedException {
649         if (isLocked()) {
650             throw new LockedException();
651         }
652         this.keepCovariance = keepCovariance;
653     }
654 
655     /**
656      * Gets estimated covariance of estimated 3D point if available.
657      * This is only available when result has been refined and covariance is
658      * kept.
659      *
660      * @return estimated covariance or null.
661      */
662     public Matrix getCovariance() {
663         return covariance;
664     }
665 
666     /**
667      * Estimates a metric 2D transformation using a robust estimator and the
668      * best set of matched 2D point correspondences found using the robust
669      * estimator.
670      *
671      * @return a metric 2D transformation.
672      * @throws LockedException          if robust estimator is locked because an
673      *                                  estimation is already in progress.
674      * @throws NotReadyException        if provided input data is not enough to start
675      *                                  the estimation.
676      * @throws RobustEstimatorException if estimation fails for any reason
677      *                                  (i.e. numerical instability, no solution available, etc).
678      */
679     public abstract MetricTransformation2D estimate() throws LockedException, NotReadyException,
680             RobustEstimatorException;
681 
682     /**
683      * Returns method being used for robust estimation.
684      *
685      * @return method being used for robust estimation.
686      */
687     public abstract RobustEstimatorMethod getMethod();
688 
689 
690     /**
691      * Creates a metric 2D transformation estimator based on 2D point
692      * correspondences and using provided robust estimator method.
693      *
694      * @param method method of a robust estimator algorithm to estimate
695      *               the best metric 2D transformation.
696      * @return an instance of metric 2D transformation estimator.
697      */
698     public static MetricTransformation2DRobustEstimator create(final RobustEstimatorMethod method) {
699         return switch (method) {
700             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator();
701             case MSAC -> new MSACMetricTransformation2DRobustEstimator();
702             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator();
703             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator();
704             default -> new RANSACMetricTransformation2DRobustEstimator();
705         };
706     }
707 
708     /**
709      * Creates a metric 2D transformation estimator based on 2D point
710      * correspondences and using provided estimator method.
711      *
712      * @param inputPoints  list of input points to be used to estimate a
713      *                     metric 2D transformation.
714      * @param outputPoints list of output points to be used to estimate a
715      *                     metric 2D transformation.
716      * @param method       method of a robust estimator algorithm to estimate the best
717      *                     metric 2D transformation.
718      * @return an instance of metric 2D transformation estimator.
719      * @throws IllegalArgumentException if provided lists of points don't have
720      *                                  the same size or their size is smaller than MINIMUM_SIZE.
721      */
722     public static MetricTransformation2DRobustEstimator create(
723             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final RobustEstimatorMethod method) {
724         return switch (method) {
725             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
726             case MSAC -> new MSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
727             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
728             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
729             default -> new RANSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
730         };
731     }
732 
733     /**
734      * Creates a metric 2D transformation estimator based on 2D point
735      * correspondences and using provided robust estimator method.
736      *
737      * @param listener listener to be notified of events such as when estimation
738      *                 starts, ends or its progress significantly changes.
739      * @param method   method of a robust estimator algorithm to estimate the best
740      *                 metric 2D transformation.
741      * @return an instance of metric 2D transformation estimator.
742      */
743     public static MetricTransformation2DRobustEstimator create(
744             final MetricTransformation2DRobustEstimatorListener listener, final RobustEstimatorMethod method) {
745         return switch (method) {
746             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener);
747             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener);
748             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(listener);
749             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(listener);
750             default -> new RANSACMetricTransformation2DRobustEstimator(listener);
751         };
752     }
753 
754     /**
755      * Creates a metric 2D transformation estimator based on 2D point
756      * correspondences and using provided robust estimator method.
757      *
758      * @param listener     listener to be notified of events such as when estimation
759      *                     starts, ends or its progress significantly changes.
760      * @param inputPoints  list of input points to be used to estimate a
761      *                     metric 2D transformation.
762      * @param outputPoints list of output points to be used to estimate a
763      *                     metric 2D transformation.
764      * @param method       method of a robust estimator algorithm to estimate the best
765      *                     metric 2D transformation.
766      * @return an instance of metric 2D transformation estimator.
767      * @throws IllegalArgumentException if provided lists of points don't have
768      *                                  the same size or their size is smaller than MINIMUM_SIZE.
769      */
770     public static MetricTransformation2DRobustEstimator create(
771             final MetricTransformation2DRobustEstimatorListener listener,
772             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final RobustEstimatorMethod method) {
773         return switch (method) {
774             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
775             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
776             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
777             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
778             default -> new RANSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
779         };
780     }
781 
782     /**
783      * Creates a metric 2D transformation estimator based on 2D point
784      * correspondences and using provided robust estimator method.
785      *
786      * @param qualityScores quality scores corresponding to each pair of matched
787      *                      points.
788      * @param method        method of a robust estimator algorithm to estimate the best
789      *                      metric 2D transformation.
790      * @return an instance of metric 2D transformation estimator.
791      * @throws IllegalArgumentException if provided quality scores length is
792      *                                  smaller than MINIMUM_SIZE (i.e. 3 matched points).
793      */
794     public static MetricTransformation2DRobustEstimator create(final double[] qualityScores,
795                                                                final RobustEstimatorMethod method) {
796         return switch (method) {
797             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator();
798             case MSAC -> new MSACMetricTransformation2DRobustEstimator();
799             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(qualityScores);
800             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(qualityScores);
801             default -> new RANSACMetricTransformation2DRobustEstimator();
802         };
803     }
804 
805     /**
806      * Creates a metric 2D transformation estimator based on 2D point
807      * correspondences and using provided robust estimator method.
808      *
809      * @param inputPoints   list of input points to be used to estimate a
810      *                      metric 2D transformation.
811      * @param outputPoints  list of output points to be used to estimate a
812      *                      metric 2D transformation.
813      * @param qualityScores quality scores corresponding to each pair of matched
814      *                      points.
815      * @param method        method of a robust estimator algorithm to estimate the best
816      *                      metric 2D transformation.
817      * @return an instance of metric 2D transformation estimator.
818      * @throws IllegalArgumentException if provided lists of points or scores
819      *                                  don't have the same size or their size is smaller than MINIMUM_SIZE.
820      */
821     public static MetricTransformation2DRobustEstimator create(
822             final List<Point2D> inputPoints, final List<Point2D> outputPoints,
823             final double[] qualityScores, final RobustEstimatorMethod method) {
824         return switch (method) {
825             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
826             case MSAC -> new MSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
827             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints, qualityScores);
828             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(inputPoints, outputPoints, qualityScores);
829             default -> new RANSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints);
830         };
831     }
832 
833     /**
834      * Creates a metric 2D transformation estimator based on 2D point
835      * correspondences and using provided robust estimator method.
836      *
837      * @param listener      listener to be notified of events such as when estimation
838      *                      starts, ends or its progress significantly changes.
839      * @param qualityScores quality scores corresponding to each pair of matched
840      *                      points.
841      * @param method        method of a robust estimator algorithm to estimate the best
842      *                      metric 2D transformation.
843      * @return an instance of metric 2D transformation estimator.
844      * @throws IllegalArgumentException if provided quality scores don't have
845      *                                  the required minimum size.
846      */
847     public static MetricTransformation2DRobustEstimator create(
848             final MetricTransformation2DRobustEstimatorListener listener, final double[] qualityScores,
849             final RobustEstimatorMethod method) {
850         return switch (method) {
851             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener);
852             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener);
853             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(listener, qualityScores);
854             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(listener, qualityScores);
855             default -> new RANSACMetricTransformation2DRobustEstimator(listener);
856         };
857     }
858 
859     /**
860      * Creates a metric 2D transformation estimator based on 2D point
861      * correspondences and using provided robust estimator method.
862      *
863      * @param listener      listener to be notified of events such as when estimation
864      *                      starts, ends or its progress significantly changes.
865      * @param inputPoints   list of input points to be used to estimate a
866      *                      metric 2D transformation.
867      * @param outputPoints  list of output points to be used to estimate a
868      *                      metric 2D transformation.
869      * @param qualityScores quality scores corresponding to each pair of matched
870      *                      points.
871      * @param method        method of a robust estimator algorithm to estimate the best
872      *                      metric 2D transformation.
873      * @return an instance of metric 2D transformation estimator.
874      * @throws IllegalArgumentException if provided lists of points don't have
875      *                                  the same size of their size is smaller than MINIMUM_SIZE.
876      */
877     public static MetricTransformation2DRobustEstimator create(
878             final MetricTransformation2DRobustEstimatorListener listener,
879             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final double[] qualityScores,
880             final RobustEstimatorMethod method) {
881         return switch (method) {
882             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
883             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
884             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(
885                     listener, inputPoints, outputPoints, qualityScores);
886             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(
887                     listener, inputPoints, outputPoints, qualityScores);
888             default -> new RANSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints);
889         };
890     }
891 
892     /**
893      * Creates a metric 2D transformation estimator based on 2D point
894      * correspondences and using provided robust estimator method.
895      *
896      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
897      * @param method                 method of a robust estimator algorithm to estimate
898      *                               the best metric 2D transformation.
899      * @return an instance of metric 2D transformation estimator.
900      */
901     public static MetricTransformation2DRobustEstimator create(
902             final boolean weakMinimumSizeAllowed, final RobustEstimatorMethod method) {
903         return switch (method) {
904             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
905             case MSAC -> new MSACMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
906             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
907             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
908             default -> new RANSACMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
909         };
910     }
911 
912     /**
913      * Creates a metric 2D transformation estimator based on 2D point
914      * correspondences and using provided estimator method.
915      *
916      * @param inputPoints            list of input points to be used to estimate a
917      *                               metric 2D transformation.
918      * @param outputPoints           list of output points to be used to estimate a
919      *                               metric 2D transformation.
920      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
921      * @param method                 method of a robust estimator algorithm to estimate the best
922      *                               metric 2D transformation.
923      * @return an instance of metric 2D transformation estimator.
924      * @throws IllegalArgumentException if provided lists of points don't have
925      *                                  the same size or their size is smaller than MINIMUM_SIZE.
926      */
927     public static MetricTransformation2DRobustEstimator create(
928             final List<Point2D> inputPoints, final List<Point2D> outputPoints,
929             final boolean weakMinimumSizeAllowed, final RobustEstimatorMethod method) {
930         return switch (method) {
931             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(
932                     inputPoints, outputPoints, weakMinimumSizeAllowed);
933             case MSAC -> new MSACMetricTransformation2DRobustEstimator(
934                     inputPoints, outputPoints, weakMinimumSizeAllowed);
935             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(
936                     inputPoints, outputPoints, weakMinimumSizeAllowed);
937             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(
938                     inputPoints, outputPoints, weakMinimumSizeAllowed);
939             default -> new RANSACMetricTransformation2DRobustEstimator(
940                     inputPoints, outputPoints, weakMinimumSizeAllowed);
941         };
942     }
943 
944     /**
945      * Creates a metric 2D transformation estimator based on 2D point
946      * correspondences and using provided robust estimator method.
947      *
948      * @param listener               listener to be notified of events such as when estimation
949      *                               starts, ends or its progress significantly changes.
950      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
951      * @param method                 method of a robust estimator algorithm to estimate the best
952      *                               metric 2D transformation.
953      * @return an instance of metric 2D transformation estimator.
954      */
955     public static MetricTransformation2DRobustEstimator create(
956             final MetricTransformation2DRobustEstimatorListener listener, final boolean weakMinimumSizeAllowed,
957             final RobustEstimatorMethod method) {
958         return switch (method) {
959             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
960             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
961             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
962             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
963             default -> new RANSACMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
964         };
965     }
966 
967     /**
968      * Creates a metric 2D transformation estimator based on 2D point
969      * correspondences and using provided robust estimator method.
970      *
971      * @param listener               listener to be notified of events such as when estimation
972      *                               starts, ends or its progress significantly changes.
973      * @param inputPoints            list of input points to be used to estimate a
974      *                               metric 2D transformation.
975      * @param outputPoints           list of output points to be used to estimate a
976      *                               metric 2D transformation.
977      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
978      * @param method                 method of a robust estimator algorithm to estimate the best
979      *                               metric 2D transformation.
980      * @return an instance of metric 2D transformation estimator.
981      * @throws IllegalArgumentException if provided lists of points don't have
982      *                                  the same size or their size is smaller than MINIMUM_SIZE.
983      */
984     public static MetricTransformation2DRobustEstimator create(
985             final MetricTransformation2DRobustEstimatorListener listener,
986             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final boolean weakMinimumSizeAllowed,
987             final RobustEstimatorMethod method) {
988         return switch (method) {
989             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
990                     weakMinimumSizeAllowed);
991             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
992                     weakMinimumSizeAllowed);
993             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
994                     weakMinimumSizeAllowed);
995             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
996                     weakMinimumSizeAllowed);
997             default -> new RANSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
998                     weakMinimumSizeAllowed);
999         };
1000     }
1001 
1002     /**
1003      * Creates a metric 2D transformation estimator based on 2D point
1004      * correspondences and using provided robust estimator method.
1005      *
1006      * @param qualityScores          quality scores corresponding to each pair of matched
1007      *                               points.
1008      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1009      * @param method                 method of a robust estimator algorithm to estimate the best
1010      *                               metric 2D transformation.
1011      * @return an instance of metric 2D transformation estimator.
1012      * @throws IllegalArgumentException if provided quality scores length is
1013      *                                  smaller than MINIMUM_SIZE (i.e. 3 matched points).
1014      */
1015     public static MetricTransformation2DRobustEstimator create(
1016             final double[] qualityScores, final boolean weakMinimumSizeAllowed, final RobustEstimatorMethod method) {
1017         return switch (method) {
1018             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
1019             case MSAC -> new MSACMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
1020             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(qualityScores, weakMinimumSizeAllowed);
1021             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(qualityScores, weakMinimumSizeAllowed);
1022             default -> new RANSACMetricTransformation2DRobustEstimator(weakMinimumSizeAllowed);
1023         };
1024     }
1025 
1026     /**
1027      * Creates a metric 2D transformation estimator based on 2D point
1028      * correspondences and using provided robust estimator method.
1029      *
1030      * @param inputPoints            list of input points to be used to estimate a
1031      *                               metric 2D transformation.
1032      * @param outputPoints           list of output points to be used to estimate a
1033      *                               metric 2D transformation.
1034      * @param qualityScores          quality scores corresponding to each pair of matched
1035      *                               points.
1036      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1037      * @param method                 method of a robust estimator algorithm to estimate the best
1038      *                               metric 2D transformation.
1039      * @return an instance of metric 2D transformation estimator.
1040      * @throws IllegalArgumentException if provided lists of points or scores
1041      *                                  don't have the same size or their size is smaller than MINIMUM_SIZE.
1042      */
1043     public static MetricTransformation2DRobustEstimator create(
1044             final List<Point2D> inputPoints, final List<Point2D> outputPoints,
1045             final double[] qualityScores, final boolean weakMinimumSizeAllowed, final RobustEstimatorMethod method) {
1046         return switch (method) {
1047             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(
1048                     inputPoints, outputPoints, weakMinimumSizeAllowed);
1049             case MSAC -> new MSACMetricTransformation2DRobustEstimator(
1050                     inputPoints, outputPoints, weakMinimumSizeAllowed);
1051             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(inputPoints, outputPoints, qualityScores,
1052                     weakMinimumSizeAllowed);
1053             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(inputPoints, outputPoints, qualityScores,
1054                     weakMinimumSizeAllowed);
1055             default -> new RANSACMetricTransformation2DRobustEstimator(
1056                     inputPoints, outputPoints, weakMinimumSizeAllowed);
1057         };
1058     }
1059 
1060     /**
1061      * Creates a metric 2D transformation estimator based on 2D point
1062      * correspondences and using provided robust estimator method.
1063      *
1064      * @param listener               listener to be notified of events such as when estimation
1065      *                               starts, ends or its progress significantly changes.
1066      * @param qualityScores          quality scores corresponding to each pair of matched
1067      *                               points.
1068      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1069      * @param method                 method of a robust estimator algorithm to estimate the best
1070      *                               metric 2D transformation.
1071      * @return an instance of metric 2D transformation estimator.
1072      * @throws IllegalArgumentException if provided quality scores don't have
1073      *                                  the required minimum size.
1074      */
1075     public static MetricTransformation2DRobustEstimator create(
1076             final MetricTransformation2DRobustEstimatorListener listener, final double[] qualityScores,
1077             final boolean weakMinimumSizeAllowed, final RobustEstimatorMethod method) {
1078         return switch (method) {
1079             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
1080             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
1081             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(
1082                     listener, qualityScores, weakMinimumSizeAllowed);
1083             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(
1084                     listener, qualityScores, weakMinimumSizeAllowed);
1085             default -> new RANSACMetricTransformation2DRobustEstimator(listener, weakMinimumSizeAllowed);
1086         };
1087     }
1088 
1089     /**
1090      * Creates a metric 2D transformation estimator based on 2D point
1091      * correspondences and using provided robust estimator method.
1092      *
1093      * @param listener               listener to be notified of events such as when estimation
1094      *                               starts, ends or its progress significantly changes.
1095      * @param inputPoints            list of input points to be used to estimate a
1096      *                               metric 2D transformation.
1097      * @param outputPoints           list of output points to be used to estimate a
1098      *                               metric 2D transformation.
1099      * @param qualityScores          quality scores corresponding to each pair of matched
1100      *                               points.
1101      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1102      * @param method                 method of a robust estimator algorithm to estimate the best
1103      *                               metric 2D transformation.
1104      * @return an instance of metric 2D transformation estimator.
1105      * @throws IllegalArgumentException if provided lists of points don't have
1106      *                                  the same size of their size is smaller than MINIMUM_SIZE.
1107      */
1108     public static MetricTransformation2DRobustEstimator create(
1109             final MetricTransformation2DRobustEstimatorListener listener,
1110             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final double[] qualityScores,
1111             final boolean weakMinimumSizeAllowed, final RobustEstimatorMethod method) {
1112         return switch (method) {
1113             case LMEDS -> new LMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
1114                     weakMinimumSizeAllowed);
1115             case MSAC -> new MSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
1116                     weakMinimumSizeAllowed);
1117             case PROSAC -> new PROSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
1118                     qualityScores, weakMinimumSizeAllowed);
1119             case PROMEDS -> new PROMedSMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
1120                     qualityScores, weakMinimumSizeAllowed);
1121             default -> new RANSACMetricTransformation2DRobustEstimator(listener, inputPoints, outputPoints,
1122                     weakMinimumSizeAllowed);
1123         };
1124     }
1125 
1126     /**
1127      * Creates a metric 2D transformation estimator based on 2D point
1128      * correspondences and using default robust estimator method.
1129      *
1130      * @return an instance of metric 2D transformation estimator.
1131      */
1132     public static MetricTransformation2DRobustEstimator create() {
1133         return create(DEFAULT_ROBUST_METHOD);
1134     }
1135 
1136     /**
1137      * Creates a metric 2D transformation estimator based on 2D point
1138      * correspondences and using default robust estimator method.
1139      *
1140      * @param inputPoints  list of input points to be used to estimate a
1141      *                     metric 2D transformation.
1142      * @param outputPoints list of output points to be used to estimate a
1143      *                     metric 2D transformation.
1144      * @return an instance of metric 2D transformation estimator.
1145      * @throws IllegalArgumentException if provided lists of points don't have
1146      *                                  the same size of their size is smaller than MINIMUM_SIZE.
1147      */
1148     public static MetricTransformation2DRobustEstimator create(
1149             final List<Point2D> inputPoints, final List<Point2D> outputPoints) {
1150         return create(inputPoints, outputPoints, DEFAULT_ROBUST_METHOD);
1151     }
1152 
1153     /**
1154      * Creates a metric 2D transformation estimator based on 2D point
1155      * correspondences and using default robust estimator method.
1156      *
1157      * @param listener listener to be notified of events such as when estimation
1158      *                 starts, ends or its progress significantly changes.
1159      * @return an instance of metric 2D transformation estimator.
1160      */
1161     public static MetricTransformation2DRobustEstimator create(
1162             final MetricTransformation2DRobustEstimatorListener listener) {
1163         return create(listener, DEFAULT_ROBUST_METHOD);
1164     }
1165 
1166     /**
1167      * Creates a metric 2D transformation estimator based on 2D point
1168      * correspondences and using default robust estimator method.
1169      *
1170      * @param listener     listener to be notified of events such as when estimation
1171      *                     starts, ends or its progress significantly changes.
1172      * @param inputPoints  list of input points to be used to estimate a
1173      *                     metric 2D transformation.
1174      * @param outputPoints list of output points to be used to estimate a
1175      *                     metric 2D transformation.
1176      * @return an instance of metric 2D transformation estimator.
1177      * @throws IllegalArgumentException if provided lists of points don't have
1178      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1179      */
1180     public static MetricTransformation2DRobustEstimator create(
1181             final MetricTransformation2DRobustEstimatorListener listener,
1182             final List<Point2D> inputPoints, final List<Point2D> outputPoints) {
1183         return create(listener, inputPoints, outputPoints, DEFAULT_ROBUST_METHOD);
1184     }
1185 
1186     /**
1187      * Creates a metric 2D transformation estimator based on 2D point
1188      * correspondences and using default robust estimator method.
1189      *
1190      * @param qualityScores quality scores corresponding to each pair of matched
1191      *                      points.
1192      * @return an instance of metric 2D transformation estimator.
1193      */
1194     public static MetricTransformation2DRobustEstimator create(final double[] qualityScores) {
1195         return create(qualityScores, DEFAULT_ROBUST_METHOD);
1196     }
1197 
1198     /**
1199      * Creates a metric 2D transformation estimator based on 2D point
1200      * correspondences and using default robust estimator method.
1201      *
1202      * @param inputPoints   list of input points to be used to estimate a
1203      *                      metric 2D transformation.
1204      * @param outputPoints  list of output points ot be used to estimate a
1205      *                      metric 2D transformation.
1206      * @param qualityScores quality scores corresponding to each pair of points.
1207      * @return an instance of metric 2D transformation estimator.
1208      * @throws IllegalArgumentException if provided lists of points don't have
1209      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1210      */
1211     public static MetricTransformation2DRobustEstimator create(
1212             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final double[] qualityScores) {
1213         return create(inputPoints, outputPoints, qualityScores, DEFAULT_ROBUST_METHOD);
1214     }
1215 
1216     /**
1217      * Creates a metric 2D transformation estimator based on 2D point
1218      * correspondences and using default robust estimator method.
1219      *
1220      * @param listener      listener to be notified of events such as when estimation
1221      *                      starts, ends or its progress significantly changes.
1222      * @param qualityScores quality scores corresponding to each pair of matched
1223      *                      points.
1224      * @return an instance of metric 2D transformation estimator.
1225      */
1226     public static MetricTransformation2DRobustEstimator create(
1227             final MetricTransformation2DRobustEstimatorListener listener, final double[] qualityScores) {
1228         return create(listener, qualityScores, DEFAULT_ROBUST_METHOD);
1229     }
1230 
1231     /**
1232      * Creates a metric 2D transformation estimator based on 2D point
1233      * correspondences and using default robust estimator method.
1234      *
1235      * @param listener      listener to be notified of events such as when estimation
1236      *                      starts, ends or its progress significantly changes.
1237      * @param inputPoints   list of input points to be used to estimate a
1238      *                      metric 2D transformation.
1239      * @param outputPoints  list of output points ot be used to estimate a
1240      *                      metric 2D transformation.
1241      * @param qualityScores quality scores corresponding to each pair of matched
1242      *                      points.
1243      * @return an instance of metric 2D transformation estimator.
1244      * @throws IllegalArgumentException if provided lists of points don't have
1245      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1246      */
1247     public static MetricTransformation2DRobustEstimator create(
1248             final MetricTransformation2DRobustEstimatorListener listener,
1249             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final double[] qualityScores) {
1250         return create(listener, inputPoints, outputPoints, qualityScores, DEFAULT_ROBUST_METHOD);
1251     }
1252 
1253     /**
1254      * Creates a metric 2D transformation estimator based on 2D point
1255      * correspondences and using default robust estimator method.
1256      *
1257      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1258      * @return an instance of metric 2D transformation estimator.
1259      */
1260     public static MetricTransformation2DRobustEstimator create(final boolean weakMinimumSizeAllowed) {
1261         return create(weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1262     }
1263 
1264     /**
1265      * Creates a metric 2D transformation estimator based on 2D point
1266      * correspondences and using default robust estimator method.
1267      *
1268      * @param inputPoints            list of input points to be used to estimate a
1269      *                               metric 2D transformation.
1270      * @param outputPoints           list of output points to be used to estimate a
1271      *                               metric 2D transformation.
1272      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1273      * @return an instance of metric 2D transformation estimator.
1274      * @throws IllegalArgumentException if provided lists of points don't have
1275      *                                  the same size of their size is smaller than MINIMUM_SIZE.
1276      */
1277     public static MetricTransformation2DRobustEstimator create(
1278             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final boolean weakMinimumSizeAllowed) {
1279         return create(inputPoints, outputPoints, weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1280     }
1281 
1282     /**
1283      * Creates a metric 2D transformation estimator based on 2D point
1284      * correspondences and using default robust estimator method.
1285      *
1286      * @param listener               listener to be notified of events such as when estimation
1287      *                               starts, ends or its progress significantly changes.
1288      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1289      * @return an instance of metric 2D transformation estimator.
1290      */
1291     public static MetricTransformation2DRobustEstimator create(
1292             final MetricTransformation2DRobustEstimatorListener listener, final boolean weakMinimumSizeAllowed) {
1293         return create(listener, weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1294     }
1295 
1296     /**
1297      * Creates a metric 2D transformation estimator based on 2D point
1298      * correspondences and using default robust estimator method.
1299      *
1300      * @param listener               listener to be notified of events such as when estimation
1301      *                               starts, ends or its progress significantly changes.
1302      * @param inputPoints            list of input points to be used to estimate a
1303      *                               metric 2D transformation.
1304      * @param outputPoints           list of output points to be used to estimate a
1305      *                               metric 2D transformation.
1306      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1307      * @return an instance of metric 2D transformation estimator.
1308      * @throws IllegalArgumentException if provided lists of points don't have
1309      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1310      */
1311     public static MetricTransformation2DRobustEstimator create(
1312             final MetricTransformation2DRobustEstimatorListener listener,
1313             final List<Point2D> inputPoints, final List<Point2D> outputPoints, final boolean weakMinimumSizeAllowed) {
1314         return create(listener, inputPoints, outputPoints, weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1315     }
1316 
1317     /**
1318      * Creates a metric 2D transformation estimator based on 2D point
1319      * correspondences and using default robust estimator method.
1320      *
1321      * @param qualityScores          quality scores corresponding to each pair of matched
1322      *                               points.
1323      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1324      * @return an instance of metric 2D transformation estimator.
1325      */
1326     public static MetricTransformation2DRobustEstimator create(
1327             final double[] qualityScores, final boolean weakMinimumSizeAllowed) {
1328         return create(qualityScores, weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1329     }
1330 
1331     /**
1332      * Creates a metric 2D transformation estimator based on 2D point
1333      * correspondences and using default robust estimator method.
1334      *
1335      * @param inputPoints            list of input points to be used to estimate a
1336      *                               metric 2D transformation.
1337      * @param outputPoints           list of output points ot be used to estimate a
1338      *                               metric 2D transformation.
1339      * @param qualityScores          quality scores corresponding to each pair of points.
1340      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1341      * @return an instance of metric 2D transformation estimator.
1342      * @throws IllegalArgumentException if provided lists of points don't have
1343      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1344      */
1345     public static MetricTransformation2DRobustEstimator create(
1346             final List<Point2D> inputPoints, final List<Point2D> outputPoints,
1347             final double[] qualityScores, final boolean weakMinimumSizeAllowed) {
1348         return create(inputPoints, outputPoints, qualityScores, weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1349     }
1350 
1351     /**
1352      * Creates a metric 2D transformation estimator based on 2D point
1353      * correspondences and using default robust estimator method.
1354      *
1355      * @param listener               listener to be notified of events such as when estimation
1356      *                               starts, ends or its progress significantly changes.
1357      * @param qualityScores          quality scores corresponding to each pair of matched
1358      *                               points.
1359      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1360      * @return an instance of metric 2D transformation estimator.
1361      */
1362     public static MetricTransformation2DRobustEstimator create(
1363             final MetricTransformation2DRobustEstimatorListener listener,
1364             final double[] qualityScores, final boolean weakMinimumSizeAllowed) {
1365         return create(listener, qualityScores, weakMinimumSizeAllowed, DEFAULT_ROBUST_METHOD);
1366     }
1367 
1368     /**
1369      * Creates a metric 2D transformation estimator based on 2D point
1370      * correspondences and using default robust estimator method.
1371      *
1372      * @param listener               listener to be notified of events such as when estimation
1373      *                               starts, ends or its progress significantly changes.
1374      * @param inputPoints            list of input points to be used to estimate a
1375      *                               metric 2D transformation.
1376      * @param outputPoints           list of output points ot be used to estimate a
1377      *                               metric 2D transformation.
1378      * @param qualityScores          quality scores corresponding to each pair of matched
1379      *                               points.
1380      * @param weakMinimumSizeAllowed true allows 2 points, false requires 3.
1381      * @return an instance of metric 2D transformation estimator.
1382      * @throws IllegalArgumentException if provided lists of points don't have
1383      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1384      */
1385     public static MetricTransformation2DRobustEstimator create(
1386             final MetricTransformation2DRobustEstimatorListener listener,
1387             final List<Point2D> inputPoints, final List<Point2D> outputPoints,
1388             final double[] qualityScores, final boolean weakMinimumSizeAllowed) {
1389         return create(listener, inputPoints, outputPoints, qualityScores, weakMinimumSizeAllowed,
1390                 DEFAULT_ROBUST_METHOD);
1391     }
1392 
1393     /**
1394      * Internal method to set lists of points to be used to estimate a
1395      * metric 2D transformation.
1396      * This method does not check whether estimator is locked or not.
1397      *
1398      * @param inputPoints  list of input points to be used to estimate a
1399      *                     metric 2D transformation.
1400      * @param outputPoints list of output points to be used to estimate a
1401      *                     metric 2D transformation.
1402      * @throws IllegalArgumentException if provided lists of points don't have
1403      *                                  the same size or their size is smaller than MINIMUM_SIZE.
1404      */
1405     private void internalSetPoints(final List<Point2D> inputPoints, final List<Point2D> outputPoints) {
1406         if (inputPoints.size() < getMinimumPoints()) {
1407             throw new IllegalArgumentException();
1408         }
1409         if (inputPoints.size() != outputPoints.size()) {
1410             throw new IllegalArgumentException();
1411         }
1412         this.inputPoints = inputPoints;
1413         this.outputPoints = outputPoints;
1414     }
1415 
1416     /**
1417      * Attempts to refine provided solution if refinement is requested.
1418      * This method returns a refined solution of the same provided solution
1419      * if refinement is not requested or has failed.
1420      * If refinement is enabled, and it is requested to keep covariance, this
1421      * method will also keep covariance of refined transformation.
1422      *
1423      * @param transformation transformation estimated by a robust estimator
1424      *                       without refinement.
1425      * @return solution after refinement (if requested) or the provided
1426      * non-refined solution if not requested or refinement failed.
1427      */
1428     protected MetricTransformation2D attemptRefine(final MetricTransformation2D transformation) {
1429         if (refineResult) {
1430             final var refiner = new MetricTransformation2DRefiner(transformation, keepCovariance, getInliersData(),
1431                     inputPoints, outputPoints, getRefinementStandardDeviation());
1432 
1433             try {
1434                 final var result = new MetricTransformation2D();
1435                 final var improved = refiner.refine(result);
1436 
1437                 if (keepCovariance) {
1438                     // keep covariance
1439                     covariance = refiner.getCovariance();
1440                 }
1441 
1442                 return improved ? result : transformation;
1443             } catch (final Exception e) {
1444                 // refinement failed, so we return input value
1445                 return transformation;
1446             }
1447         } else {
1448             return transformation;
1449         }
1450     }
1451 
1452     /**
1453      * Gets standard deviation used for Levenberg-Marquardt fitting during
1454      * refinement.
1455      * Returned value gives an indication of how much variance each residual
1456      * has.
1457      * Typically, this value is related to the threshold used on each robust
1458      * estimation, since residuals of found inliers are within the range of
1459      * such threshold.
1460      *
1461      * @return standard deviation used for refinement.
1462      */
1463     protected abstract double getRefinementStandardDeviation();
1464 
1465 }