#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>

#include <sstream>

void distanceTransform(int size)
{
    std::stringstream ss;
    int rectangleSize = size / 4;

    // Create sample Mat with white rectangle
    cv::Mat data = cv::Mat::zeros(size, size, CV_8UC1);
    cv::rectangle(data, cv::Point(rectangleSize, rectangleSize), cv::Point(size - rectangleSize, size - rectangleSize), cv::Scalar::all(255), CV_FILLED);
    cv::Mat copy;
    data.copyTo(copy);

    ss << size << "-rectangle.tiff";
    cv::imwrite(ss.str(), data);

    // distance transform with [Borgefors86]
    cv::distanceTransform(data, data, CV_DIST_L2, CV_DIST_MASK_5);
    ss.str("");
    ss << size << "-borgefors86.tiff";
    cv::imwrite(ss.str(), data);

    cv::threshold(data, data, 0, 255, CV_THRESH_BINARY);
    ss.str("");
    ss << size << "-borgefors86-binary.tiff";
    cv::imwrite(ss.str(), data);

    // distance transform with [Felzenszwalb04]
    cv::distanceTransform(copy, copy, CV_DIST_L2, CV_DIST_MASK_PRECISE);
    ss.str("");
    ss << size << "-felzenszwalb04.tiff";
    cv::imwrite(ss.str(), copy);

    cv::threshold(copy, copy, 0, 255, CV_THRESH_BINARY);
    ss.str("");
    ss << size << "-felzenszwalb04-binary.tiff";
    cv::imwrite(ss.str(), copy);
}

int main()
{
    distanceTransform(2500);
    distanceTransform(10000);

    return 0;
}