/* Copyright (c) 2012 Patrick Ruoff * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. */ #include "point_extractor.h" #include #ifdef DEBUG_EXTRACTION # include "opentrack-compat/timer.hpp" #endif PointExtractor::PointExtractor(){ //if (!AllocConsole()){} //else SetConsoleTitle("debug"); //freopen("CON", "w", stdout); //freopen("CON", "w", stderr); } // ---------------------------------------------------------------------------- std::vector PointExtractor::extract_points(cv::Mat& frame) { const int W = frame.cols; const int H = frame.rows; // convert to grayscale cv::Mat frame_gray; cv::cvtColor(frame, frame_gray, cv::COLOR_RGB2GRAY); const int region_size_min = s.min_point_size; const int region_size_max = s.max_point_size; const int thres = s.threshold; struct simple_blob { double radius; cv::Vec2d pos; double confid; bool taken; double area; simple_blob(double radius, const cv::Vec2d& pos, double confid, double area) : radius(radius), pos(pos), confid(confid), taken(false), area(area) { //qDebug() << "radius" << radius << "pos" << pos[0] << pos[1] << "confid" << confid; } bool inside(const simple_blob& other) { cv::Vec2d tmp = pos - other.pos; return sqrt(tmp.dot(tmp)) < radius; } }; // mask for everything that passes the threshold (or: the upper threshold of the hysteresis) cv::Mat frame_bin = cv::Mat::zeros(H, W, CV_8U); std::vector blobs; std::vector> contours; { cv::Mat frame_bin_; cv::threshold(frame_gray, frame_bin_, thres, 255, cv::THRESH_BINARY); frame_bin.setTo(170, frame_bin_); cv::findContours(frame_bin_, contours, CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE); } int cnt = 0; for (auto& c : contours) { if (cnt++ > 30) break; const auto m = cv::moments(cv::Mat(c)); const double area = m.m00; if (area == 0.) continue; const cv::Vec2d pos(m.m10 / m.m00, m.m01 / m.m00); double radius; // following based on OpenCV SimpleBlobDetector { std::vector dists; for (auto& k : c) { dists.push_back(cv::norm(pos - cv::Vec2d(k.x, k.y))); } std::sort(dists.begin(), dists.end()); radius = (dists[(dists.size() - 1)/2] + dists[dists.size()/2])/2; } if (radius < region_size_min || radius > region_size_max) continue; double confid = 1; { double denominator = std::sqrt(std::pow(2 * m.mu11, 2) + std::pow(m.mu20 - m.mu02, 2)); const double eps = 1e-2; if (denominator > eps) { double cosmin = (m.mu20 - m.mu02) / denominator; double sinmin = 2 * m.mu11 / denominator; double cosmax = -cosmin; double sinmax = -sinmin; double imin = 0.5 * (m.mu20 + m.mu02) - 0.5 * (m.mu20 - m.mu02) * cosmin - m.mu11 * sinmin; double imax = 0.5 * (m.mu20 + m.mu02) - 0.5 * (m.mu20 - m.mu02) * cosmax - m.mu11 * sinmax; confid = imin / imax; } } // end SimpleBlobDetector { char buf[64]; sprintf(buf, "%.2fpx %.2fc", radius, confid); cv::putText(frame, buf, cv::Point(pos[0]+30, pos[1]+20), cv::FONT_HERSHEY_DUPLEX, 1, cv::Scalar(0, 0, 255), 1); } blobs.push_back(simple_blob(radius, pos, confid, area)); } // clear old points points.clear(); using b = const simple_blob; std::sort(blobs.begin(), blobs.end(), [](b& b1, b& b2) {return b1.confid > b2.confid;}); for (auto& b : blobs) { cv::Vec2f p((b.pos[0] - W/2)/W, -(b.pos[1] - H/2)/W); points.push_back(p); } // draw output image std::vector channels_; cv::split(frame, channels_); std::vector channels; { cv::Mat frame_bin__ = frame_bin * .5; channels.push_back(channels_[0] + frame_bin__); channels.push_back(channels_[1] - frame_bin__); channels.push_back(channels_[2] - frame_bin__); cv::merge(channels, frame); } return points; }