mirror of
https://github.com/opencv/opencv.git
synced 2024-12-24 17:18:28 +08:00
90 lines
2.5 KiB
C++
90 lines
2.5 KiB
C++
/**
|
|
* @file houghclines.cpp
|
|
* @brief This program demonstrates line finding with the Hough transform
|
|
*/
|
|
|
|
#include "opencv2/imgcodecs.hpp"
|
|
#include "opencv2/highgui.hpp"
|
|
#include "opencv2/imgproc.hpp"
|
|
|
|
using namespace cv;
|
|
using namespace std;
|
|
|
|
int main(int argc, char** argv)
|
|
{
|
|
// Declare the output variables
|
|
Mat dst, cdst, cdstP;
|
|
|
|
//![load]
|
|
const char* default_file = "../../../data/sudoku.png";
|
|
const char* filename = argc >=2 ? argv[1] : default_file;
|
|
|
|
// Loads an image
|
|
Mat src = imread( filename, IMREAD_GRAYSCALE );
|
|
|
|
// Check if image is loaded fine
|
|
if(src.empty()){
|
|
printf(" Error opening image\n");
|
|
printf(" Program Arguments: [image_name -- default %s] \n", default_file);
|
|
return -1;
|
|
}
|
|
//![load]
|
|
|
|
//![edge_detection]
|
|
// Edge detection
|
|
Canny(src, dst, 50, 200, 3);
|
|
//![edge_detection]
|
|
|
|
// Copy edges to the images that will display the results in BGR
|
|
cvtColor(dst, cdst, COLOR_GRAY2BGR);
|
|
cdstP = cdst.clone();
|
|
|
|
//![hough_lines]
|
|
// Standard Hough Line Transform
|
|
vector<Vec2f> lines; // will hold the results of the detection
|
|
HoughLines(dst, lines, 1, CV_PI/180, 150, 0, 0 ); // runs the actual detection
|
|
//![hough_lines]
|
|
//![draw_lines]
|
|
// Draw the lines
|
|
for( size_t i = 0; i < lines.size(); i++ )
|
|
{
|
|
float rho = lines[i][0], theta = lines[i][1];
|
|
Point pt1, pt2;
|
|
double a = cos(theta), b = sin(theta);
|
|
double x0 = a*rho, y0 = b*rho;
|
|
pt1.x = cvRound(x0 + 1000*(-b));
|
|
pt1.y = cvRound(y0 + 1000*(a));
|
|
pt2.x = cvRound(x0 - 1000*(-b));
|
|
pt2.y = cvRound(y0 - 1000*(a));
|
|
line( cdst, pt1, pt2, Scalar(0,0,255), 3, CV_AA);
|
|
}
|
|
//![draw_lines]
|
|
|
|
//![hough_lines_p]
|
|
// Probabilistic Line Transform
|
|
vector<Vec4i> linesP; // will hold the results of the detection
|
|
HoughLinesP(dst, linesP, 1, CV_PI/180, 50, 50, 10 ); // runs the actual detection
|
|
//![hough_lines_p]
|
|
//![draw_lines_p]
|
|
// Draw the lines
|
|
for( size_t i = 0; i < linesP.size(); i++ )
|
|
{
|
|
Vec4i l = linesP[i];
|
|
line( cdstP, Point(l[0], l[1]), Point(l[2], l[3]), Scalar(0,0,255), 3, LINE_AA);
|
|
}
|
|
//![draw_lines_p]
|
|
|
|
//![imshow]
|
|
// Show results
|
|
imshow("Source", src);
|
|
imshow("Detected Lines (in red) - Standard Hough Line Transform", cdst);
|
|
imshow("Detected Lines (in red) - Probabilistic Line Transform", cdstP);
|
|
//![imshow]
|
|
|
|
//![exit]
|
|
// Wait and Exit
|
|
waitKey();
|
|
return 0;
|
|
//![exit]
|
|
}
|