#include <iostream>

#include <opencv/cv.h>

#include <opencv/highgui.h>

using namespace std;

using namespace cv;

int

main(int argc, char** argv)

{

     const int rows = 256;

     const int cols = 256;

     Mat img(rows, cols, CV_8UC1, Scalar(255));

     line(img, Point(0, 10), Point(255, 10), Scalar(0), 2, 4);

     line(img, Point(-5, 20), Point(260, 20), Scalar(0), 2, 4);

     line(img, Point(10, 0), Point(10, 255), Scalar(0), 2, 4);

     float x0 = 0.0/pow(2.0, -2.0);

     float x1 = 255.0/pow(2.0, -2.0);

     float y = 30.5/pow(2.0, -2.0);

     line(img, Point(int(x0), int(y)), Point(int(x1), int(y)),

          Scalar(0), 2, 4, 2);

     cerr << "saving linetest.png...\n";

     imwrite("linetest.png", img);

     return 0;

}