return keep;
}
-#if defined(CV_MAJOR_VERSION) && (CV_MAJOR_VERSION >= 3)
namespace {
+const int INTERSECT_NONE = 0;
+const int INTERSECT_PARTIAL = 1;
+const int INTERSECT_FULL = 2;
+
+class RotatedRect {
+ public:
+ RotatedRect() {}
+ RotatedRect(
+ const Eigen::Vector2f& p_center,
+ const Eigen::Vector2f& p_size,
+ float p_angle)
+ : center(p_center), size(p_size), angle(p_angle) {}
+ void get_vertices(Eigen::Vector2f* pt) const {
+ // M_PI / 180. == 0.01745329251
+ double _angle = angle * 0.01745329251;
+ float b = (float)cos(_angle) * 0.5f;
+ float a = (float)sin(_angle) * 0.5f;
+
+ pt[0].x() = center.x() - a * size.y() - b * size.x();
+ pt[0].y() = center.y() + b * size.y() - a * size.x();
+ pt[1].x() = center.x() + a * size.y() - b * size.x();
+ pt[1].y() = center.y() - b * size.y() - a * size.x();
+ pt[2] = 2 * center - pt[0];
+ pt[3] = 2 * center - pt[1];
+ }
+ Eigen::Vector2f center;
+ Eigen::Vector2f size;
+ float angle;
+};
template <class Derived>
-cv::RotatedRect bbox_to_rotated_rect(const Eigen::ArrayBase<Derived>& box) {
+RotatedRect bbox_to_rotated_rect(const Eigen::ArrayBase<Derived>& box) {
CAFFE_ENFORCE_EQ(box.size(), 5);
// cv::RotatedRect takes angle to mean clockwise rotation, but RRPN bbox
// representation means counter-clockwise rotation.
- return cv::RotatedRect(
- cv::Point2f(box[0], box[1]), cv::Size2f(box[2], box[3]), -box[4]);
+ return RotatedRect(
+ Eigen::Vector2f(box[0], box[1]),
+ Eigen::Vector2f(box[2], box[3]),
+ -box[4]);
+}
+
+// Eigen doesn't seem to support 2d cross product, so we make one here
+float cross_2d(const Eigen::Vector2f& A, const Eigen::Vector2f& B) {
+ return A.x() * B.y() - B.x() * A.y();
}
-// TODO: cvfix_rotatedRectangleIntersection is a replacement function for
+// rotated_rect_intersection_pts is a replacement function for
// cv::rotatedRectangleIntersection, which has a bug due to float underflow
-// When OpenCV version is upgraded to be >= 4.0,
-// we can remove this replacement function.
// For anyone interested, here're the PRs on OpenCV:
// https://github.com/opencv/opencv/issues/12221
// https://github.com/opencv/opencv/pull/12222
-int cvfix_rotatedRectangleIntersection(
- const cv::RotatedRect& rect1,
- const cv::RotatedRect& rect2,
- cv::OutputArray intersectingRegion) {
+// Note that we do not check if the number of intersections is <= 8 in this case
+int rotated_rect_intersection_pts(
+ const RotatedRect& rect1,
+ const RotatedRect& rect2,
+ Eigen::Vector2f* intersections,
+ int& num) {
// Used to test if two points are the same
const float samePointEps = 0.00001f;
const float EPS = 1e-14;
+ num = 0; // number of intersections
- cv::Point2f vec1[4], vec2[4];
- cv::Point2f pts1[4], pts2[4];
-
- std::vector<cv::Point2f> intersection;
+ Eigen::Vector2f vec1[4], vec2[4], pts1[4], pts2[4];
- rect1.points(pts1);
- rect2.points(pts2);
-
- int ret = cv::INTERSECT_FULL;
+ rect1.get_vertices(pts1);
+ rect2.get_vertices(pts2);
// Specical case of rect1 == rect2
- {
- bool same = true;
+ bool same = true;
- for (int i = 0; i < 4; i++) {
- if (fabs(pts1[i].x - pts2[i].x) > samePointEps ||
- (fabs(pts1[i].y - pts2[i].y) > samePointEps)) {
- same = false;
- break;
- }
+ for (int i = 0; i < 4; i++) {
+ if (fabs(pts1[i].x() - pts2[i].x()) > samePointEps ||
+ (fabs(pts1[i].y() - pts2[i].y()) > samePointEps)) {
+ same = false;
+ break;
}
+ }
- if (same) {
- intersection.resize(4);
-
- for (int i = 0; i < 4; i++) {
- intersection[i] = pts1[i];
- }
-
- cv::Mat(intersection).copyTo(intersectingRegion);
-
- return cv::INTERSECT_FULL;
+ if (same) {
+ for (int i = 0; i < 4; i++) {
+ intersections[i] = pts1[i];
}
+ num = 4;
+ return INTERSECT_FULL;
}
// Line vector
// A line from p1 to p2 is: p1 + (p2-p1)*t, t=[0,1]
for (int i = 0; i < 4; i++) {
- vec1[i].x = pts1[(i + 1) % 4].x - pts1[i].x;
- vec1[i].y = pts1[(i + 1) % 4].y - pts1[i].y;
-
- vec2[i].x = pts2[(i + 1) % 4].x - pts2[i].x;
- vec2[i].y = pts2[(i + 1) % 4].y - pts2[i].y;
+ vec1[i] = pts1[(i + 1) % 4] - pts1[i];
+ vec2[i] = pts2[(i + 1) % 4] - pts2[i];
}
// Line test - test all line combos for intersection
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
// Solve for 2x2 Ax=b
- float x21 = pts2[j].x - pts1[i].x;
- float y21 = pts2[j].y - pts1[i].y;
-
- const auto& l1 = vec1[i];
- const auto& l2 = vec2[j];
// This takes care of parallel lines
- float det = l2.x * l1.y - l1.x * l2.y;
+ float det = cross_2d(vec2[j], vec1[i]);
if (std::fabs(det) <= EPS) {
continue;
}
- float t1 = (l2.x * y21 - l2.y * x21) / det;
- float t2 = (l1.x * y21 - l1.y * x21) / det;
+ auto vec12 = pts2[j] - pts1[i];
+
+ float t1 = cross_2d(vec2[j], vec12) / det;
+ float t2 = cross_2d(vec1[i], vec12) / det;
if (t1 >= 0.0f && t1 <= 1.0f && t2 >= 0.0f && t2 <= 1.0f) {
- float xi = pts1[i].x + vec1[i].x * t1;
- float yi = pts1[i].y + vec1[i].y * t1;
- intersection.push_back(cv::Point2f(xi, yi));
+ intersections[num++] = pts1[i] + t1 * vec1[i];
}
}
}
- if (!intersection.empty()) {
- ret = cv::INTERSECT_PARTIAL;
- }
-
// Check for vertices from rect1 inside rect2
- for (int i = 0; i < 4; i++) {
- // We do a sign test to see which side the point lies.
- // If the point all lie on the same sign for all 4 sides of the rect,
- // then there's an intersection
- int posSign = 0;
- int negSign = 0;
+ {
+ const auto& AB = vec2[0];
+ const auto& DA = vec2[3];
+ auto ABdotAB = AB.squaredNorm();
+ auto ADdotAD = DA.squaredNorm();
+ for (int i = 0; i < 4; i++) {
+ // assume ABCD is the rectangle, and P is the point to be judged
+ // P is inside ABCD iff. P's projection on AB lies within AB
+ // and P's projection on AD lies within AD
- float x = pts1[i].x;
- float y = pts1[i].y;
+ auto AP = pts1[i] - pts2[0];
- for (int j = 0; j < 4; j++) {
- // line equation: Ax + By + C = 0
- // see which side of the line this point is at
-
- // float causes underflow!
- // Original version:
- // float A = -vec2[j].y;
- // float B = vec2[j].x;
- // float C = -(A * pts2[j].x + B * pts2[j].y);
- // float s = A * x + B * y + C;
-
- double A = -vec2[j].y;
- double B = vec2[j].x;
- double C = -(A * pts2[j].x + B * pts2[j].y);
- double s = A * x + B * y + C;
-
- if (s >= 0) {
- posSign++;
- } else {
- negSign++;
- }
- }
+ auto APdotAB = AP.dot(AB);
+ auto APdotAD = -AP.dot(DA);
- if (posSign == 4 || negSign == 4) {
- intersection.push_back(pts1[i]);
+ if ((APdotAB >= 0) && (APdotAD >= 0) && (APdotAB <= ABdotAB) &&
+ (APdotAD <= ADdotAD)) {
+ intersections[num++] = pts1[i];
+ }
}
}
// Reverse the check - check for vertices from rect2 inside rect1
- for (int i = 0; i < 4; i++) {
- // We do a sign test to see which side the point lies.
- // If the point all lie on the same sign for all 4 sides of the rect,
- // then there's an intersection
- int posSign = 0;
- int negSign = 0;
-
- float x = pts2[i].x;
- float y = pts2[i].y;
-
- for (int j = 0; j < 4; j++) {
- // line equation: Ax + By + C = 0
- // see which side of the line this point is at
-
- // float causes underflow!
- // Original version:
- // float A = -vec1[j].y;
- // float B = vec1[j].x;
- // float C = -(A * pts1[j].x + B * pts1[j].y);
- // float s = A*x + B*y + C;
-
- double A = -vec1[j].y;
- double B = vec1[j].x;
- double C = -(A * pts1[j].x + B * pts1[j].y);
- double s = A * x + B * y + C;
-
- if (s >= 0) {
- posSign++;
- } else {
- negSign++;
- }
- }
+ {
+ const auto& AB = vec1[0];
+ const auto& DA = vec1[3];
+ auto ABdotAB = AB.squaredNorm();
+ auto ADdotAD = DA.squaredNorm();
+ for (int i = 0; i < 4; i++) {
+ auto AP = pts2[i] - pts1[0];
- if (posSign == 4 || negSign == 4) {
- intersection.push_back(pts2[i]);
- }
- }
+ auto APdotAB = AP.dot(AB);
+ auto APdotAD = -AP.dot(DA);
- // Get rid of dupes
- for (int i = 0; i < (int)intersection.size() - 1; i++) {
- for (size_t j = i + 1; j < intersection.size(); j++) {
- float dx = intersection[i].x - intersection[j].x;
- float dy = intersection[i].y - intersection[j].y;
- // can be a really small number, need double here
- double d2 = dx * dx + dy * dy;
-
- if (d2 < samePointEps * samePointEps) {
- // Found a dupe, remove it
- std::swap(intersection[j], intersection.back());
- intersection.pop_back();
- j--; // restart check
+ if ((APdotAB >= 0) && (APdotAD >= 0) && (APdotAB <= ABdotAB) &&
+ (APdotAD <= ADdotAD)) {
+ intersections[num++] = pts2[i];
}
}
}
- if (intersection.empty()) {
- return cv::INTERSECT_NONE;
- }
+ return num ? INTERSECT_PARTIAL : INTERSECT_NONE;
+}
- // If this check fails then it means we're getting dupes
- // CV_Assert(intersection.size() <= 8);
-
- // At this point, there might still be some edge cases failing the check above
- // However, it doesn't affect the result of polygon area,
- // even if the number of intersections is greater than 8.
- // Therefore, we just print out these cases for now instead of assertion.
- // TODO: These cases should provide good reference for improving the accuracy
- // for intersection computation above (for example, we should use
- // cross-product/dot-product of vectors instead of line equation to
- // judge the relationships between the points and line segments)
-
- if (intersection.size() > 8) {
- LOG(ERROR) << "Intersection size = " << intersection.size();
- LOG(ERROR) << "Rect 1:";
- for (int i = 0; i < 4; i++) {
- LOG(ERROR) << " (" << pts1[i].x << " ," << pts1[i].y << "),";
+// Compute convex hull using Graham scan algorithm
+int convex_hull_graham(
+ const Eigen::Vector2f* p,
+ const int& num_in,
+ Eigen::Vector2f* q) {
+ int m = 0;
+ std::vector<int> order;
+
+ // start from point with minimum y
+ int t = 0;
+ for (int i = 0; i < num_in; i++) {
+ if (p[i].y() < p[t].y()) {
+ t = i;
}
- LOG(ERROR) << "Rect 2:";
- for (int i = 0; i < 4; i++) {
- LOG(ERROR) << " (" << pts2[i].x << " ," << pts2[i].y << "),";
+ }
+ order.push_back(t);
+ do {
+ t = order[m] + 1;
+ if (t >= num_in) {
+ t = 0;
}
- LOG(ERROR) << "Intersections:";
- for (auto& p : intersection) {
- LOG(ERROR) << " (" << p.x << " ," << p.y << "),";
+ for (int i = 0; i < num_in; i++) {
+ if (cross_2d(p[i] - p[order[m]], p[t] - p[order[m]]) < 0) {
+ t = i;
+ }
}
- }
-
- cv::Mat(intersection).copyTo(intersectingRegion);
+ m++;
+ order.push_back(t);
+ } while (order[m] != order[0]);
+ // ignore the ending point (which is the same as the starting point)
+ for (int i = 0; i < m; i++)
+ q[i] = p[order[i]];
+ return m;
+}
- return ret;
+double polygon_area(const Eigen::Vector2f* q, const int& m) {
+ if (m <= 2)
+ return 0;
+ double area = 0;
+ for (int i = 1; i < m - 1; i++)
+ area += fabs(cross_2d(q[i] - q[0], q[i + 1] - q[0]));
+ return area / 2.0;
}
/**
* Returns the intersection area of two rotated rectangles.
*/
double rotated_rect_intersection(
- const cv::RotatedRect& rect1,
- const cv::RotatedRect& rect2) {
- std::vector<cv::Point2f> intersectPts, orderedPts;
+ const RotatedRect& rect1,
+ const RotatedRect& rect2) {
+ // There are up to 16 intersections returned from
+ // rotated_rect_intersection_pts
+ Eigen::Vector2f intersectPts[16], orderedPts[16];
+ int num = 0; // number of intersections
// Find points of intersection
- // TODO: cvfix_rotatedRectangleIntersection is a replacement function for
+ // TODO: rotated_rect_intersection_pts is a replacement function for
// cv::rotatedRectangleIntersection, which has a bug due to float underflow
- // When OpenCV version is upgraded to be >= 4.0,
- // we can remove this replacement function and use the following instead:
- // auto ret = cv::rotatedRectangleIntersection(rect1, rect2, intersectPts);
// For anyone interested, here're the PRs on OpenCV:
// https://github.com/opencv/opencv/issues/12221
// https://github.com/opencv/opencv/pull/12222
- auto ret = cvfix_rotatedRectangleIntersection(rect1, rect2, intersectPts);
- if (intersectPts.size() <= 2) {
+ // Note: it doesn't matter if #intersections is greater than 8 here
+ auto ret = rotated_rect_intersection_pts(rect1, rect2, intersectPts, num);
+ CAFFE_ENFORCE(num <= 16);
+ if (num <= 2)
return 0.0;
- }
// If one rectangle is fully enclosed within another, return the area
// of the smaller one early.
- if (ret == cv::INTERSECT_FULL) {
- return std::min(rect1.size.area(), rect2.size.area());
+ if (ret == INTERSECT_FULL) {
+ return std::min(
+ rect1.size.x() * rect1.size.y(), rect2.size.x() * rect2.size.y());
}
// Convex Hull to order the intersection points in clockwise or
// counter-clockwise order and find the countour area.
- cv::convexHull(intersectPts, orderedPts);
- return cv::contourArea(orderedPts);
+ int num_convex = convex_hull_graham(intersectPts, num, orderedPts);
+ return polygon_area(orderedPts, num_convex);
}
} // namespace
auto heights = proposals.col(3);
EArrX areas = widths * heights;
- std::vector<cv::RotatedRect> rotated_rects(proposals.rows());
+ std::vector<RotatedRect> rotated_rects(proposals.rows());
for (int i = 0; i < proposals.rows(); ++i) {
rotated_rects[i] = bbox_to_rotated_rect(proposals.row(i));
}
auto heights = proposals.col(3);
EArrX areas = widths * heights;
- std::vector<cv::RotatedRect> rotated_rects(proposals.rows());
+ std::vector<RotatedRect> rotated_rects(proposals.rows());
for (int i = 0; i < proposals.rows(); ++i) {
rotated_rects[i] = bbox_to_rotated_rect(proposals.row(i));
}
return keep;
}
-#endif // CV_MAJOR_VERSION >= 3
template <class Derived1, class Derived2>
std::vector<int> nms_cpu(
const std::vector<int>& sorted_indices,
float thresh,
int topN = -1) {
-#if defined(CV_MAJOR_VERSION) && (CV_MAJOR_VERSION >= 3)
CAFFE_ENFORCE(proposals.cols() == 4 || proposals.cols() == 5);
if (proposals.cols() == 4) {
// Upright boxes
// Rotated boxes with angle info
return nms_cpu_rotated(proposals, scores, sorted_indices, thresh, topN);
}
-#else
- return nms_cpu_upright(proposals, scores, sorted_indices, thresh, topN);
-#endif // CV_MAJOR_VERSION >= 3
}
// Greedy non-maximum suppression for proposed bounding boxes
float score_thresh = 0.001,
unsigned int method = 1,
int topN = -1) {
-#if defined(CV_MAJOR_VERSION) && (CV_MAJOR_VERSION >= 3)
CAFFE_ENFORCE(proposals.cols() == 4 || proposals.cols() == 5);
if (proposals.cols() == 4) {
// Upright boxes
method,
topN);
}
-#else
- return soft_nms_cpu_upright(
- out_scores,
- proposals,
- scores,
- indices,
- sigma,
- overlap_thresh,
- score_thresh,
- method,
- topN);
-#endif // CV_MAJOR_VERSION >= 3
}
template <class Derived1, class Derived2, class Derived3>