RobotVision/transformations.cpp at master · nathanchu/RobotVision · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
#include "transformations.h"

#include <opencv2/opencv.hpp>
#include <vector>

namespace robot_vision {

Transformation::Transformation(const cv::Mat& translation, const cv::Mat& rotation) {
  mat_ = (cv::Mat_<double>(4, 4) <<
    rotation.at<double>(0, 0), rotation.at<double>(0, 1), rotation.at<double>(0, 2), translation.at<double>(0, 0),
    rotation.at<double>(1, 0), rotation.at<double>(1, 1), rotation.at<double>(1, 2), translation.at<double>(1, 0),
    rotation.at<double>(2, 0), rotation.at<double>(2, 1), rotation.at<double>(2, 2), translation.at<double>(2, 0),
    0, 0, 0, 1
  );
}

Transformation::Transformation(const cv::Mat& rotation, const cv::Vec3d& translation) {
  mat_ = (cv::Mat_<double>(4, 4) <<
    rotation.at<double>(0, 0), rotation.at<double>(0, 1), rotation.at<double>(0, 2), translation[0],
    rotation.at<double>(1, 0), rotation.at<double>(1, 1), rotation.at<double>(1, 2), translation[1],
    rotation.at<double>(2, 0), rotation.at<double>(2, 1), rotation.at<double>(2, 2), translation[2],
    0, 0, 0, 1
  );
}

cv::Mat Transformation::Self() {
  return mat_;
}

std::vector<double> Transformation::ToVector() const {
  std::vector<double> out;
  out.reserve(16);
  for (int i=0; i<4; ++i) {
    for (int j=0; j<4; ++j) {
      out.push_back(mat_.at<double>(i, j));
    }
  }
  return out;
}

Transformation Transformation::operator*(const Transformation& other) const {
  return Transformation(mat_*other.mat_);
}

Transformation Transformation::operator/(const Transformation& other) const {
  return Transformation(mat_/other.mat_);
}

Transformation Transformation::operator*(double other) const {
  return Transformation(mat_*other);
}

Transformation Transformation::operator/(double other) const {
  return Transformation(mat_/other);
}

Transformation Transformation::operator+(const Transformation& other) const {
  return Transformation(mat_+other.mat_);
}

Transformation Transformation::operator-(const Transformation& other) const {
  return Transformation(mat_-other.mat_);
}

cv::Mat Transformation::ToVec() {
  cv::Mat out = (cv::Mat_<double>(4, 1) <<
    mat_.at<double>(0, 3),
    mat_.at<double>(1, 3),
    mat_.at<double>(2, 3),
    1
  );
  return out;
}

cv::Vec3d Transformation::ToVec3d() {
  cv::Vec3d out = cv::Vec3d(
    mat_.at<double>(0, 3),
    mat_.at<double>(1, 3),
    mat_.at<double>(2, 3)
  );
  return out;
}

cv::Mat Transformation::ToRot() {
  cv::Mat out = (cv::Mat_<double>(3, 3) <<
    mat_.at<double>(0, 0), mat_.at<double>(0, 1), mat_.at<double>(0, 2),
    mat_.at<double>(1, 0), mat_.at<double>(1, 1), mat_.at<double>(1, 2),
    mat_.at<double>(2, 0), mat_.at<double>(2, 1), mat_.at<double>(2, 2)
  );
  return out;
}

Transformation Transformation::Inverse() {
  cv::Mat inv;
  cv::invert(mat_, inv);
  return Transformation(inv);
}

Transformation TransformationAverage(const std::vector<Transformation>& mats) {
  Transformation s((cv::Mat_<double>(4, 4) <<
    0, 0, 0, 0,
    0, 0, 0, 0,
    0, 0, 0, 0,
    0, 0, 0, 0
  ));
  for (Transformation e : mats) {
    s = s + e;
  }
  s = s/mats.size();
  cv::Mat U, W, Vt;
  cv::SVD::compute(s.ToRot(), W, U, Vt);

  double det_U = cv::determinant(U);
  double det_Vt = cv::determinant(Vt);

  if (abs(det_U*det_Vt - 1) <= 0.01) {
    Transformation out(U*Vt, s.ToVec3d());
    return out;
  } else {
    cv::Mat flip = (cv::Mat_<double>(3, 3) <<
      1, 0, 0,
      0, 1, 0,
      0, 0, -1
    );
    Transformation out(U*(Vt*flip), s.ToVec3d());
    return out;
  }
}

double TransformationDifference(const Transformation& a, const Transformation& b, double rotation_weight, double translation_weight) {
  Transformation s = a-b;
  cv::Mat rot = s.ToRot();
  cv::Vec3d pos = s.ToVec3d();
  double sum = 0;
  for (int i=0; i<3; ++i) {
    for (int j=0; j<3; ++j) {
      double c = rot.at<double>(i, j)*rotation_weight;
      sum += c;
    }
  }
  for (int i=0; i<3; ++i) {
    double c = pos[i]*translation_weight;
    sum += c*c;
  }
  return sum;
}

}  // namespace robot_vision