RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator.java
/*
* Copyright (C) 2015 Alberto Irurueta Carro (alberto@irurueta.com)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.irurueta.geometry.estimators;
import com.irurueta.geometry.Line2D;
import com.irurueta.geometry.PinholeCamera;
import com.irurueta.geometry.Plane;
import com.irurueta.numerical.robust.RANSACRobustEstimator;
import com.irurueta.numerical.robust.RANSACRobustEstimatorListener;
import com.irurueta.numerical.robust.RobustEstimator;
import com.irurueta.numerical.robust.RobustEstimatorException;
import com.irurueta.numerical.robust.RobustEstimatorMethod;
import java.util.ArrayList;
import java.util.List;
/**
* Finds the best pinhole camera for provided collections of matched lines and
* planes using RANSAC algorithm.
*/
@SuppressWarnings("DuplicatedCode")
public class RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator
extends DLTLinePlaneCorrespondencePinholeCameraRobustEstimator {
/**
* Constant defining default threshold to determine whether planes are
* inliers or not.
* Residuals to determine whether planes are inliers or not are computed by
* comparing two planes algebraically (e.g. doing the dot product of their
* parameters).
* A residual of 0 indicates that dot product was 1 or -1 and lines were
* equal.
* A residual of 1 indicates that dot product was 0 and lines were
* orthogonal.
* If dot product between lines is -1, then although their director vectors
* are opposed, lines are considered equal, since sign changes are not taken
* into account and their residuals will be 0.
*/
public static final double DEFAULT_THRESHOLD = 1e-6;
/**
* Minimum value that can be set as threshold.
* Threshold must be strictly greater than 0.0.
*/
public static final double MIN_THRESHOLD = 0.0;
/**
* Indicates that by default inliers will only be computed but not kept.
*/
public static final boolean DEFAULT_COMPUTE_AND_KEEP_INLIERS = false;
/**
* Indicates that by default residuals will only be computed but not kept.
*/
public static final boolean DEFAULT_COMPUTE_AND_KEEP_RESIDUALS = false;
/**
* Threshold to determine whether planes are inliers or not when testing
* possible estimation solutions.
* The threshold refers to the amount of error a possible solution has on a
* plane respect the back-projected plane of a line using estimated camera.
*/
private double threshold;
/**
* Indicates whether inliers must be computed and kept.
*/
private boolean computeAndKeepInliers;
/**
* Indicates whether residuals must be computed and kept.
*/
private boolean computeAndKeepResiduals;
/**
* Constructor.
*/
public RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator() {
super();
threshold = DEFAULT_THRESHOLD;
computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
}
/**
* Constructor with lists of matched planes and 2D lines to estimate a
* pinhole camera.
* Points and lines in the lists located at the same position are considered
* to be matched. Hence, both lists must have the same size, and their size
* must be greater or equal than MIN_NUMBER_OF_LINE_PLANE_CORRESPONDENCES
* (4 matches).
*
* @param planes list of planes used to estimate a pinhole camera.
* @param lines list of corresponding projected 2D lines used to estimate
* a pinhole camera.
* @throws IllegalArgumentException if provided lists don't have the same
* size or their size is smaller than required minimum size (4 matches).
*/
public RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator(
final List<Plane> planes, final List<Line2D> lines) {
super(planes, lines);
threshold = DEFAULT_THRESHOLD;
computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
}
/**
* Constructor with listener.
*
* @param listener listener to be notified of events such as when estimation
* starts, ends or its progress significantly changes.
*/
public RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator(
final PinholeCameraRobustEstimatorListener listener) {
super(listener);
threshold = DEFAULT_THRESHOLD;
computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
}
/**
* Constructor with listener and lists of matched planes and 2D lines to
* estimate a pinhole camera.
* Points and lines in the lists located at the same position are considered
* to be matched. Hence, both lists must have the same size, and their size
* must be greater or equal than MIN_NUMBER_OF_LINE_PLANE_CORRESPONDENCES
* (4 matches).
*
* @param listener listener to be notified of events such as when estimation
* starts, ends or its progress significantly changes.
* @param planes list of planes used to estimate a pinhole camera.
* @param lines list of corresponding projected 2D lines used to estimate
* a pinhole camera.
* @throws IllegalArgumentException if provided lists don't have the same
* size or their size is smaller than required minimum size (4 matches).
*/
public RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator(
final PinholeCameraRobustEstimatorListener listener, final List<Plane> planes, final List<Line2D> lines) {
super(listener, planes, lines);
threshold = DEFAULT_THRESHOLD;
computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
}
/**
* Returns threshold to determine whether planes are inliers or not when
* testing possible estimation solutions.
* The threshold refers to the amount of error a possible solution has on a
* plane respect the back-projected plane of a line using estimated camera
* Residuals to determine whether planes are inliers or not are computed by
* comparing two planes algebraically (e.g. doing the dot product of their
* parameters).
* A residual of 0 indicates that dot product was 1 or -1 and planes were
* equal.
* A residual of 1 indicates that dot product was 0 and planes were
* orthogonal.
* If dot product between planes is -1, then although their director vectors
* are opposed, planes are considered equal, since sign changes are not
* taken into account and their residuals will be 0.
*
* @return threshold to determine whether matched planes are inliers or not.
*/
public double getThreshold() {
return threshold;
}
/**
* Sets threshold to determine whether planes are inliers or not when
* testing possible estimation solutions.
* The threshold refers to the amount of error a possible solution has on a
* plane respect the back-projected plane of a line using estimated camera
* Residuals to determine whether planes are inliers or not are computed by
* comparing two planes algebraically (e.g. doing the dot product of their
* parameters).
* A residual of 0 indicates that dot product was 1 or -1 and planes were
* equal.
* A residual of 1 indicates that dot product was 0 and planes were
* orthogonal.
* If dot product between planes is -1, then although their director vectors
* are opposed, planes are considered equal, since sign changes are not
* taken into account and their residuals will be 0.
*
* @param threshold threshold to determine whether matched planes are
* inliers or not.
* @throws IllegalArgumentException if provided value is equal or less than
* zero.
* @throws LockedException if robust estimator is locked because an
* estimation is already in progress.
*/
public void setThreshold(final double threshold) throws LockedException {
if (isLocked()) {
throw new LockedException();
}
if (threshold <= MIN_THRESHOLD) {
throw new IllegalArgumentException();
}
this.threshold = threshold;
}
/**
* Indicates whether inliers must be computed and kept.
*
* @return true if inliers must be computed and kept, false if inliers
* only need to be computed but not kept.
*/
public boolean isComputeAndKeepInliersEnabled() {
return computeAndKeepInliers;
}
/**
* Specifies whether inliers must be computed and kept.
*
* @param computeAndKeepInliers true if inliers must be computed and kept,
* false if inliers only need to be computed but not kept.
* @throws LockedException if estimator is locked.
*/
public void setComputeAndKeepInliersEnabled(final boolean computeAndKeepInliers) throws LockedException {
if (isLocked()) {
throw new LockedException();
}
this.computeAndKeepInliers = computeAndKeepInliers;
}
/**
* Indicates whether residuals must be computed and kept.
*
* @return true if residuals must be computed and kept, false if residuals
* only need to be computed but not kept.
*/
public boolean isComputeAndKeepResidualsEnabled() {
return computeAndKeepResiduals;
}
/**
* Specifies whether residuals must be computed and kept.
*
* @param computeAndKeepResiduals true if residuals must be computed and
* kept, false if residuals only need to be computed but not kept.
* @throws LockedException if estimator is locked.
*/
public void setComputeAndKeepResidualsEnabled(final boolean computeAndKeepResiduals) throws LockedException {
if (isLocked()) {
throw new LockedException();
}
this.computeAndKeepResiduals = computeAndKeepResiduals;
}
/**
* Estimates a pinhole camera using a robust estimator and
* the best set of matched 2D line/3D plane correspondences found using the
* robust estimator.
*
* @return a pinhole camera.
* @throws LockedException if robust estimator is locked because an
* estimation is already in progress.
* @throws NotReadyException if provided input data is not enough to start
* the estimation.
* @throws RobustEstimatorException if estimation fails for any reason
* (i.e. numerical instability, no solution available, etc).
*/
@Override
public PinholeCamera estimate() throws LockedException, NotReadyException, RobustEstimatorException {
if (isLocked()) {
throw new LockedException();
}
if (!isReady()) {
throw new NotReadyException();
}
// pinhole camera estimator using DLT (Direct Linear Transform) algorithm
final var nonRobustEstimator = new DLTLinePlaneCorrespondencePinholeCameraEstimator();
nonRobustEstimator.setLMSESolutionAllowed(false);
// suggestions
nonRobustEstimator.setSuggestSkewnessValueEnabled(isSuggestSkewnessValueEnabled());
nonRobustEstimator.setSuggestedSkewnessValue(getSuggestedSkewnessValue());
nonRobustEstimator.setSuggestHorizontalFocalLengthEnabled(isSuggestHorizontalFocalLengthEnabled());
nonRobustEstimator.setSuggestedHorizontalFocalLengthValue(getSuggestedHorizontalFocalLengthValue());
nonRobustEstimator.setSuggestVerticalFocalLengthEnabled(isSuggestVerticalFocalLengthEnabled());
nonRobustEstimator.setSuggestedVerticalFocalLengthValue(getSuggestedVerticalFocalLengthValue());
nonRobustEstimator.setSuggestAspectRatioEnabled(isSuggestAspectRatioEnabled());
nonRobustEstimator.setSuggestedAspectRatioValue(getSuggestedAspectRatioValue());
nonRobustEstimator.setSuggestPrincipalPointEnabled(isSuggestPrincipalPointEnabled());
nonRobustEstimator.setSuggestedPrincipalPointValue(getSuggestedPrincipalPointValue());
nonRobustEstimator.setSuggestRotationEnabled(isSuggestRotationEnabled());
nonRobustEstimator.setSuggestedRotationValue(getSuggestedRotationValue());
nonRobustEstimator.setSuggestCenterEnabled(isSuggestCenterEnabled());
nonRobustEstimator.setSuggestedCenterValue(getSuggestedCenterValue());
final var innerEstimator = new RANSACRobustEstimator<>(new RANSACRobustEstimatorListener<PinholeCamera>() {
// 3D planes for a subset of samples
private final List<Plane> subsetPlanes = new ArrayList<>();
// 2D lines for a subset of samples
private final List<Line2D> subsetLines = new ArrayList<>();
@Override
public double getThreshold() {
return threshold;
}
@Override
public int getTotalSamples() {
return planes.size();
}
@Override
public int getSubsetSize() {
return LinePlaneCorrespondencePinholeCameraEstimator.MIN_NUMBER_OF_LINE_PLANE_CORRESPONDENCES;
}
@Override
public void estimatePreliminarSolutions(final int[] samplesIndices, final List<PinholeCamera> solutions) {
subsetPlanes.clear();
subsetPlanes.add(planes.get(samplesIndices[0]));
subsetPlanes.add(planes.get(samplesIndices[1]));
subsetPlanes.add(planes.get(samplesIndices[2]));
subsetPlanes.add(planes.get(samplesIndices[3]));
subsetLines.clear();
subsetLines.add(lines.get(samplesIndices[0]));
subsetLines.add(lines.get(samplesIndices[1]));
subsetLines.add(lines.get(samplesIndices[2]));
subsetLines.add(lines.get(samplesIndices[3]));
try {
nonRobustEstimator.setLists(subsetPlanes, subsetLines);
final var cam = nonRobustEstimator.estimate();
solutions.add(cam);
} catch (final Exception e) {
// if lines/planes configuration is degenerate, no solution is added
}
}
@Override
public double computeResidual(final PinholeCamera currentEstimation, final int i) {
final var inputLine = lines.get(i);
final var inputPlane = planes.get(i);
return singleBackprojectionResidual(currentEstimation, inputLine, inputPlane);
}
@Override
public boolean isReady() {
return RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator.this.isReady();
}
@Override
public void onEstimateStart(final RobustEstimator<PinholeCamera> estimator) {
if (listener != null) {
listener.onEstimateStart(
RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator.this);
}
}
@Override
public void onEstimateEnd(final RobustEstimator<PinholeCamera> estimator) {
if (listener != null) {
listener.onEstimateEnd(RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator.this);
}
}
@Override
public void onEstimateNextIteration(final RobustEstimator<PinholeCamera> estimator, final int iteration) {
if (listener != null) {
listener.onEstimateNextIteration(
RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator.this, iteration);
}
}
@Override
public void onEstimateProgressChange(final RobustEstimator<PinholeCamera> estimator, final float progress) {
if (listener != null) {
listener.onEstimateProgressChange(
RANSACDLTLinePlaneCorrespondencePinholeCameraRobustEstimator.this, progress);
}
}
});
try {
locked = true;
inliersData = null;
innerEstimator.setComputeAndKeepInliersEnabled(computeAndKeepInliers || refineResult);
innerEstimator.setComputeAndKeepResidualsEnabled(computeAndKeepResiduals || refineResult);
innerEstimator.setConfidence(confidence);
innerEstimator.setMaxIterations(maxIterations);
innerEstimator.setProgressDelta(progressDelta);
final var result = innerEstimator.estimate();
inliersData = innerEstimator.getInliersData();
return attemptRefine(result, nonRobustEstimator.getMaxSuggestionWeight());
} catch (final com.irurueta.numerical.LockedException e) {
throw new LockedException(e);
} catch (final com.irurueta.numerical.NotReadyException e) {
throw new NotReadyException(e);
} finally {
locked = false;
}
}
/**
* Returns method being used for robust estimation.
*
* @return method being used for robust estimation.
*/
@Override
public RobustEstimatorMethod getMethod() {
return RobustEstimatorMethod.RANSAC;
}
/**
* Gets standard deviation used for Levenberg-Marquardt fitting during
* refinement.
* Returned value gives an indication of how much variance each residual
* has.
* Typically, this value is related to the threshold used on each robust
* estimation, since residuals of found inliers are within the range of
* such threshold.
*
* @return standard deviation used for refinement.
*/
@Override
protected double getRefinementStandardDeviation() {
return threshold;
}
}