mirror of
https://github.com/opencv/opencv.git
synced 2024-12-15 09:49:13 +08:00
97 lines
3.3 KiB
Java
97 lines
3.3 KiB
Java
/**
|
|
* @file HoughLines.java
|
|
* @brief This program demonstrates line finding with the Hough transform
|
|
*/
|
|
|
|
import org.opencv.core.*;
|
|
import org.opencv.core.Point;
|
|
import org.opencv.highgui.HighGui;
|
|
import org.opencv.imgcodecs.Imgcodecs;
|
|
import org.opencv.imgproc.Imgproc;
|
|
|
|
class HoughLinesRun {
|
|
|
|
public void run(String[] args) {
|
|
// Declare the output variables
|
|
Mat dst = new Mat(), cdst = new Mat(), cdstP;
|
|
|
|
//! [load]
|
|
String default_file = "../../../../data/sudoku.png";
|
|
String filename = ((args.length > 0) ? args[0] : default_file);
|
|
|
|
// Load an image
|
|
Mat src = Imgcodecs.imread(filename, Imgcodecs.IMREAD_GRAYSCALE);
|
|
|
|
// Check if image is loaded fine
|
|
if( src.empty() ) {
|
|
System.out.println("Error opening image!");
|
|
System.out.println("Program Arguments: [image_name -- default "
|
|
+ default_file +"] \n");
|
|
System.exit(-1);
|
|
}
|
|
//! [load]
|
|
|
|
//! [edge_detection]
|
|
// Edge detection
|
|
Imgproc.Canny(src, dst, 50, 200, 3, false);
|
|
//! [edge_detection]
|
|
|
|
// Copy edges to the images that will display the results in BGR
|
|
Imgproc.cvtColor(dst, cdst, Imgproc.COLOR_GRAY2BGR);
|
|
cdstP = cdst.clone();
|
|
|
|
//! [hough_lines]
|
|
// Standard Hough Line Transform
|
|
Mat lines = new Mat(); // will hold the results of the detection
|
|
Imgproc.HoughLines(dst, lines, 1, Math.PI/180, 150); // runs the actual detection
|
|
//! [hough_lines]
|
|
//! [draw_lines]
|
|
// Draw the lines
|
|
for (int x = 0; x < lines.rows(); x++) {
|
|
double rho = lines.get(x, 0)[0],
|
|
theta = lines.get(x, 0)[1];
|
|
|
|
double a = Math.cos(theta), b = Math.sin(theta);
|
|
double x0 = a*rho, y0 = b*rho;
|
|
Point pt1 = new Point(Math.round(x0 + 1000*(-b)), Math.round(y0 + 1000*(a)));
|
|
Point pt2 = new Point(Math.round(x0 - 1000*(-b)), Math.round(y0 - 1000*(a)));
|
|
Imgproc.line(cdst, pt1, pt2, new Scalar(0, 0, 255), 3, Imgproc.LINE_AA, 0);
|
|
}
|
|
//! [draw_lines]
|
|
|
|
//! [hough_lines_p]
|
|
// Probabilistic Line Transform
|
|
Mat linesP = new Mat(); // will hold the results of the detection
|
|
Imgproc.HoughLinesP(dst, linesP, 1, Math.PI/180, 50, 50, 10); // runs the actual detection
|
|
//! [hough_lines_p]
|
|
//! [draw_lines_p]
|
|
// Draw the lines
|
|
for (int x = 0; x < linesP.rows(); x++) {
|
|
double[] l = linesP.get(x, 0);
|
|
Imgproc.line(cdstP, new Point(l[0], l[1]), new Point(l[2], l[3]), new Scalar(0, 0, 255), 3, Imgproc.LINE_AA, 0);
|
|
}
|
|
//! [draw_lines_p]
|
|
|
|
//! [imshow]
|
|
// Show results
|
|
HighGui.imshow("Source", src);
|
|
HighGui.imshow("Detected Lines (in red) - Standard Hough Line Transform", cdst);
|
|
HighGui.imshow("Detected Lines (in red) - Probabilistic Line Transform", cdstP);
|
|
//! [imshow]
|
|
|
|
//! [exit]
|
|
// Wait and Exit
|
|
HighGui.waitKey();
|
|
System.exit(0);
|
|
//! [exit]
|
|
}
|
|
}
|
|
|
|
public class HoughLines {
|
|
public static void main(String[] args) {
|
|
// Load the native library.
|
|
System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
|
|
new HoughLinesRun().run(args);
|
|
}
|
|
}
|