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1   /*
2    * Copyright (C) 2015 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.geometry.CoincidentPointsException;
19  import com.irurueta.geometry.CoordinatesType;
20  import com.irurueta.geometry.Point3D;
21  import com.irurueta.geometry.ProjectiveTransformation3D;
22  import com.irurueta.numerical.robust.PROSACRobustEstimator;
23  import com.irurueta.numerical.robust.PROSACRobustEstimatorListener;
24  import com.irurueta.numerical.robust.RobustEstimator;
25  import com.irurueta.numerical.robust.RobustEstimatorException;
26  import com.irurueta.numerical.robust.RobustEstimatorMethod;
27  
28  import java.util.List;
29  
30  /**
31   * Finds the best projective 3D transformation for provided collections of
32   * matched 3D points using PROSAC algorithm.
33   */
34  @SuppressWarnings("DuplicatedCode")
35  public class PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator
36          extends PointCorrespondenceProjectiveTransformation3DRobustEstimator {
37  
38      /**
39       * Constant defining default threshold to determine whether points are
40       * inliers or not.
41       * By default, 1.0 is considered a good value for cases where measures are
42       * done on pixels, since typically the minimum resolution is 1 pixel.
43       */
44      public static final double DEFAULT_THRESHOLD = 1.0;
45  
46      /**
47       * Minimum value that can be set as threshold.
48       * Threshold must be strictly greater than 0.0.
49       */
50      public static final double MIN_THRESHOLD = 0.0;
51  
52      /**
53       * Indicates that by default inliers will only be computed but not kept.
54       */
55      public static final boolean DEFAULT_COMPUTE_AND_KEEP_INLIERS = false;
56  
57      /**
58       * Indicates that by default residuals will only be computed but not kept.
59       */
60      public static final boolean DEFAULT_COMPUTE_AND_KEEP_RESIDUALS = false;
61  
62      /**
63       * Threshold to determine whether points are inliers or not when testing
64       * possible estimation solutions.
65       * The threshold refers to the amount of error (i.e. distance) a possible
66       * solution has on a matched pair of points.
67       */
68      private double threshold;
69  
70      /**
71       * Quality scores corresponding to each pair of matched points.
72       * The larger the score value the better the quality of the matching.
73       */
74      private double[] qualityScores;
75  
76      /**
77       * Indicates whether inliers must be computed and kept.
78       */
79      private boolean computeAndKeepInliers;
80  
81      /**
82       * Indicates whether residuals must be computed and kept.
83       */
84      private boolean computeAndKeepResiduals;
85  
86      /**
87       * Constructor.
88       */
89      public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator() {
90          super();
91          threshold = DEFAULT_THRESHOLD;
92          computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
93          computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
94      }
95  
96      /**
97       * Constructor with lists of points to be used to estimate a projective 3D
98       * transformation.
99       * Points in the list located at the same position are considered to be
100      * matched. Hence, both lists must have the same size, and their size must
101      * be greater or equal than MINIMUM_SIZE.
102      *
103      * @param inputPoints  list of input points to be used to estimate a
104      *                     projective 3D transformation.
105      * @param outputPoints list of output points to be used to estimate a
106      *                     projective 3D transformation.
107      * @throws IllegalArgumentException if provided lists of points don't have
108      *                                  the same size or their size is smaller than MINIMUM_SIZE.
109      */
110     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(
111             final List<Point3D> inputPoints, final List<Point3D> outputPoints) {
112         super(inputPoints, outputPoints);
113         threshold = DEFAULT_THRESHOLD;
114         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
115         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
116     }
117 
118     /**
119      * Constructor.
120      *
121      * @param listener listener to be notified of events such as when estimation
122      *                 starts, ends or its progress significantly changes.
123      */
124     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(
125             final ProjectiveTransformation3DRobustEstimatorListener listener) {
126         super(listener);
127         threshold = DEFAULT_THRESHOLD;
128         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
129         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
130     }
131 
132     /**
133      * Constructor with listener and lists of points to be used to estimate a
134      * projective 3D transformation.
135      * Points in the list located at the same position are considered to be
136      * matched. Hence, both lists must have the same size, and their size must
137      * be greater or equal than MINIMUM_SIZE.
138      *
139      * @param listener     listener to be notified of events such as when estimation
140      *                     stars, ends or its progress significantly changes.
141      * @param inputPoints  list of input points to be used to estimate a
142      *                     projective 3D transformation.
143      * @param outputPoints list of output points to be used to estimate a
144      *                     projective 3D transformation.
145      * @throws IllegalArgumentException if provided lists of points don't have
146      *                                  the same size or their size is smaller than MINIMUM_SIZE.
147      */
148     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(
149             final ProjectiveTransformation3DRobustEstimatorListener listener,
150             final List<Point3D> inputPoints, final List<Point3D> outputPoints) {
151         super(listener, inputPoints, outputPoints);
152         threshold = DEFAULT_THRESHOLD;
153         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
154         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
155     }
156 
157     /**
158      * Constructor.
159      *
160      * @param qualityScores quality scores corresponding to each pair of matched
161      *                      points.
162      * @throws IllegalArgumentException if provided quality scores length is
163      *                                  smaller than MINIMUM_SIZE (i.e. 3 samples).
164      */
165     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(final double[] qualityScores) {
166         super();
167         threshold = DEFAULT_THRESHOLD;
168         internalSetQualityScores(qualityScores);
169         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
170         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
171     }
172 
173     /**
174      * Constructor with lists of points to be used to estimate a projective 3D
175      * transformation.
176      * Points in the list located at the same position are considered to be
177      * matched. Hence, both lists must have the same size, and their size must
178      * be greater or equal than MINIMUM_SIZE.
179      *
180      * @param inputPoints   list of input points to be used to estimate a
181      *                      projective 3D transformation.
182      * @param outputPoints  list of output points to be used to estimate a
183      *                      projective 3D transformation.
184      * @param qualityScores quality scores corresponding to each pair of matched
185      *                      points.
186      * @throws IllegalArgumentException if provided lists of points and array
187      *                                  of quality scores don't have the same size or their size is smaller than
188      *                                  MINIMUM_SIZE.
189      */
190     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(
191             final List<Point3D> inputPoints, final List<Point3D> outputPoints, final double[] qualityScores) {
192         super(inputPoints, outputPoints);
193 
194         if (qualityScores.length != inputPoints.size()) {
195             throw new IllegalArgumentException();
196         }
197 
198         threshold = DEFAULT_THRESHOLD;
199         internalSetQualityScores(qualityScores);
200         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
201         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
202     }
203 
204     /**
205      * Constructor.
206      *
207      * @param listener      listener to be notified of events such as when estimation
208      *                      starts, ends or its progress significantly changes.
209      * @param qualityScores quality scores corresponding to each pair of matched
210      *                      points.
211      * @throws IllegalArgumentException if provided quality scores length is
212      *                                  smaller than MINIMUM_SIZE (i.e. 3 samples).
213      */
214     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(
215             final ProjectiveTransformation3DRobustEstimatorListener listener, final double[] qualityScores) {
216         super(listener);
217         threshold = DEFAULT_THRESHOLD;
218         internalSetQualityScores(qualityScores);
219         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
220         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
221     }
222 
223     /**
224      * Constructor with listener and lists of points to be used to estimate a
225      * projective 3D transformation.
226      * Points in the list located at the same position are considered to be
227      * matched. Hence, both lists must have the same size, and their size must
228      * be greater or equal than MINIMUM_SIZE.
229      *
230      * @param listener      listener to be notified of events such as when estimation
231      *                      starts, ends or its progress significantly changes.
232      * @param inputPoints   list of input points to be used to estimate a
233      *                      projective 3D transformation.
234      * @param outputPoints  list of output points to be used to estimate a
235      *                      projective 3D transformation.
236      * @param qualityScores quality scores corresponding to each pair of matched
237      *                      points.
238      * @throws IllegalArgumentException if provided lists of points don't have
239      *                                  the same size or their size is smaller than MINIMUM_SIZE.
240      */
241     public PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator(
242             final ProjectiveTransformation3DRobustEstimatorListener listener,
243             final List<Point3D> inputPoints, List<Point3D> outputPoints, final double[] qualityScores) {
244         super(listener, inputPoints, outputPoints);
245 
246         if (qualityScores.length != inputPoints.size()) {
247             throw new IllegalArgumentException();
248         }
249 
250         threshold = DEFAULT_THRESHOLD;
251         internalSetQualityScores(qualityScores);
252         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
253         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
254     }
255 
256     /**
257      * Returns threshold to determine whether points are inliers or not when
258      * testing possible estimation solutions.
259      * The threshold refers to the amount of error (i.e. Euclidean distance) a
260      * possible solution has on a matched pair of points.
261      *
262      * @return threshold to determine whether points are inliers or not when
263      * testing possible estimation solutions.
264      */
265     public double getThreshold() {
266         return threshold;
267     }
268 
269     /**
270      * Sets threshold to determine whether points are inliers or not when
271      * testing possible estimation solutions.
272      * The threshold refers to the amount of error (i.e. Euclidean distance) a
273      * possible solution has on a matched pair of points.
274      *
275      * @param threshold threshold to determine whether points are inliers or not.
276      * @throws IllegalArgumentException if provided values is equal or less than
277      *                                  zero.
278      * @throws LockedException          if robust estimator is locked because an
279      *                                  estimation is already in progress.
280      */
281     public void setThreshold(final double threshold) throws LockedException {
282         if (isLocked()) {
283             throw new LockedException();
284         }
285         if (threshold <= MIN_THRESHOLD) {
286             throw new IllegalArgumentException();
287         }
288         this.threshold = threshold;
289     }
290 
291     /**
292      * Returns quality scores corresponding to each pair of matched points.
293      * The larger the score value the better the quality of the matching.
294      *
295      * @return quality scores corresponding to each pair of matched points.
296      */
297     @Override
298     public double[] getQualityScores() {
299         return qualityScores;
300     }
301 
302     /**
303      * Sets quality scores corresponding to each pair of matched points.
304      * The larger the score value the better the quality of the matching.
305      *
306      * @param qualityScores quality scores corresponding to each pair of matched
307      *                      points.
308      * @throws LockedException          if robust estimator is locked because an
309      *                                  estimation is already in progress.
310      * @throws IllegalArgumentException if provided quality scores length is
311      *                                  smaller than MINIMUM_SIZE (i.e. 3 samples).
312      */
313     @Override
314     public void setQualityScores(final double[] qualityScores) throws LockedException {
315         if (isLocked()) {
316             throw new LockedException();
317         }
318         internalSetQualityScores(qualityScores);
319     }
320 
321     /**
322      * Indicates if estimator is ready to start the projective 2D transformation
323      * estimation.
324      * This is true when input data (i.e. lists of matched points and quality
325      * scores) are provided and a minimum of MINIMUM_SIZE points are available.
326      *
327      * @return true if estimator is ready, false otherwise.
328      */
329     @Override
330     public boolean isReady() {
331         return super.isReady() && qualityScores != null && qualityScores.length == inputPoints.size();
332     }
333 
334     /**
335      * Indicates whether inliers must be computed and kept.
336      *
337      * @return true if inliers must be computed and kept, false if inliers
338      * only need to be computed but not kept.
339      */
340     public boolean isComputeAndKeepInliersEnabled() {
341         return computeAndKeepInliers;
342     }
343 
344     /**
345      * Specifies whether inliers must be computed and kept.
346      *
347      * @param computeAndKeepInliers true if inliers must be computed and kept,
348      *                              false if inliers only need to be computed but not kept.
349      * @throws LockedException if estimator is locked.
350      */
351     public void setComputeAndKeepInliersEnabled(final boolean computeAndKeepInliers) throws LockedException {
352         if (isLocked()) {
353             throw new LockedException();
354         }
355         this.computeAndKeepInliers = computeAndKeepInliers;
356     }
357 
358     /**
359      * Indicates whether residuals must be computed and kept.
360      *
361      * @return true if residuals must be computed and kept, false if residuals
362      * only need to be computed but not kept.
363      */
364     public boolean isComputeAndKeepResidualsEnabled() {
365         return computeAndKeepResiduals;
366     }
367 
368     /**
369      * Specifies whether residuals must be computed and kept.
370      *
371      * @param computeAndKeepResiduals true if residuals must be computed and
372      *                                kept, false if residuals only need to be computed but not kept.
373      * @throws LockedException if estimator is locked.
374      */
375     public void setComputeAndKeepResidualsEnabled(final boolean computeAndKeepResiduals) throws LockedException {
376         if (isLocked()) {
377             throw new LockedException();
378         }
379         this.computeAndKeepResiduals = computeAndKeepResiduals;
380     }
381 
382     /**
383      * Estimates a projective 3D transformation using a robust estimator and
384      * the best set of matched 3D point correspondences found using the robust
385      * estimator.
386      *
387      * @return a projective 3D transformation.
388      * @throws LockedException          if robust estimator is locked because an
389      *                                  estimation is already in progress.
390      * @throws NotReadyException        if provided input data is not enough to start
391      *                                  the estimation.
392      * @throws RobustEstimatorException if estimation fails for any reason
393      *                                  (i.e. numerical instability, no solution available, etc).
394      */
395     @Override
396     public ProjectiveTransformation3D estimate() throws LockedException, NotReadyException, RobustEstimatorException {
397         if (isLocked()) {
398             throw new LockedException();
399         }
400         if (!isReady()) {
401             throw new NotReadyException();
402         }
403 
404         final var innerEstimator = new PROSACRobustEstimator<>(
405                 new PROSACRobustEstimatorListener<ProjectiveTransformation3D>() {
406 
407                     // point to be reused when computing residuals
408                     private final Point3D testPoint = Point3D.create(CoordinatesType.HOMOGENEOUS_COORDINATES);
409 
410                     @Override
411                     public double getThreshold() {
412                         return threshold;
413                     }
414 
415                     @Override
416                     public int getTotalSamples() {
417                         return inputPoints.size();
418                     }
419 
420                     @Override
421                     public int getSubsetSize() {
422                         return ProjectiveTransformation3DRobustEstimator.MINIMUM_SIZE;
423                     }
424 
425                     @Override
426                     public void estimatePreliminarSolutions(
427                             final int[] samplesIndices, final List<ProjectiveTransformation3D> solutions) {
428                         final var inputPoint1 = inputPoints.get(samplesIndices[0]);
429                         final var inputPoint2 = inputPoints.get(samplesIndices[1]);
430                         final var inputPoint3 = inputPoints.get(samplesIndices[2]);
431                         final var inputPoint4 = inputPoints.get(samplesIndices[3]);
432                         final var inputPoint5 = inputPoints.get(samplesIndices[4]);
433 
434                         final var outputPoint1 = outputPoints.get(samplesIndices[0]);
435                         final var outputPoint2 = outputPoints.get(samplesIndices[1]);
436                         final var outputPoint3 = outputPoints.get(samplesIndices[2]);
437                         final var outputPoint4 = outputPoints.get(samplesIndices[3]);
438                         final var outputPoint5 = outputPoints.get(samplesIndices[4]);
439 
440                         try {
441                             final var transformation = new ProjectiveTransformation3D(inputPoint1, inputPoint2,
442                                     inputPoint3, inputPoint4, inputPoint5, outputPoint1, outputPoint2, outputPoint3,
443                                     outputPoint4, outputPoint5);
444                             solutions.add(transformation);
445                         } catch (final CoincidentPointsException e) {
446                             // if points are coincident, no solution is added
447                         }
448                     }
449 
450                     @Override
451                     public double computeResidual(final ProjectiveTransformation3D currentEstimation, final int i) {
452                         final var inputPoint = inputPoints.get(i);
453                         final var outputPoint = outputPoints.get(i);
454 
455                         // transform input point and store result in mTestPoint
456                         currentEstimation.transform(inputPoint, testPoint);
457 
458                         return outputPoint.distanceTo(testPoint);
459                     }
460 
461                     @Override
462                     public boolean isReady() {
463                         return PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator.this.isReady();
464                     }
465 
466                     @Override
467                     public void onEstimateStart(final RobustEstimator<ProjectiveTransformation3D> estimator) {
468                         if (listener != null) {
469                             listener.onEstimateStart(
470                                     PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator.this);
471                         }
472                     }
473 
474                     @Override
475                     public void onEstimateEnd(final RobustEstimator<ProjectiveTransformation3D> estimator) {
476                         if (listener != null) {
477                             listener.onEstimateEnd(
478                                     PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator.this);
479                         }
480                     }
481 
482                     @Override
483                     public void onEstimateNextIteration(final RobustEstimator<ProjectiveTransformation3D> estimator,
484                             final int iteration) {
485                         if (listener != null) {
486                             listener.onEstimateNextIteration(
487                                     PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator.this,
488                                     iteration);
489                         }
490                     }
491 
492                     @Override
493                     public void onEstimateProgressChange(
494                             final RobustEstimator<ProjectiveTransformation3D> estimator, final float progress) {
495                         if (listener != null) {
496                             listener.onEstimateProgressChange(
497                                     PROSACPointCorrespondenceProjectiveTransformation3DRobustEstimator.this,
498                                     progress);
499                         }
500                     }
501 
502                     @Override
503                     public double[] getQualityScores() {
504                         return qualityScores;
505                     }
506                 });
507 
508         try {
509             locked = true;
510             inliersData = null;
511             innerEstimator.setComputeAndKeepInliersEnabled(computeAndKeepInliers || refineResult);
512             innerEstimator.setComputeAndKeepResidualsEnabled(computeAndKeepResiduals || refineResult);
513             innerEstimator.setConfidence(confidence);
514             innerEstimator.setMaxIterations(maxIterations);
515             innerEstimator.setProgressDelta(progressDelta);
516             final var transformation = innerEstimator.estimate();
517             inliersData = innerEstimator.getInliersData();
518             return attemptRefine(transformation);
519         } catch (final com.irurueta.numerical.LockedException e) {
520             throw new LockedException(e);
521         } catch (final com.irurueta.numerical.NotReadyException e) {
522             throw new NotReadyException(e);
523         } finally {
524             locked = false;
525         }
526     }
527 
528     /**
529      * Returns method being used for robust estimation.
530      *
531      * @return method being used for robust estimation.
532      */
533     @Override
534     public RobustEstimatorMethod getMethod() {
535         return RobustEstimatorMethod.PROSAC;
536     }
537 
538     /**
539      * Gets standard deviation used for Levenberg-Marquardt fitting during
540      * refinement.
541      * Returned value gives an indication of how much variance each residual
542      * has.
543      * Typically, this value is related to the threshold used on each robust
544      * estimation, since residuals of found inliers are within the range of
545      * such threshold.
546      *
547      * @return standard deviation used for refinement.
548      */
549     @Override
550     protected double getRefinementStandardDeviation() {
551         return threshold;
552     }
553 
554     /**
555      * Sets quality scores corresponding to each pair of matched points.
556      * This method is used internally and does not check whether instance is
557      * locked or not.
558      *
559      * @param qualityScores quality scores to be set.
560      * @throws IllegalArgumentException if provided quality scores length is
561      *                                  smaller than MINIMUM_SIZE.
562      */
563     private void internalSetQualityScores(final double[] qualityScores) {
564         if (qualityScores.length < MINIMUM_SIZE) {
565             throw new IllegalArgumentException();
566         }
567 
568         this.qualityScores = qualityScores;
569     }
570 
571 }