JavaCV 边缘检测方法与线圆检测

1． 用OpenCV验证常用边缘检测方法，

1public class EdgeDetection {
2
3    private final  static String path=System.getProperty("user.dir")+"\\catton.jpg";
4    static{
5        platformUtils.loadLibraries();
6    }
7
8    public static void main(String[] args) {
9        Mat srcimage;
10        //读取一张灰度图片
11        srcimage= Imgcodecs.imread(path,Imgcodecs.IMREAD_COLOR);
12        if (srcimage.empty()) {
13            System.err.println("加载图片出错，请检查图片路径！");
14            return;
15        }
16        System.out.println(srcimage);
17        // 索贝尔水平检测 边缘检测
18       // Imgproc.Sobel(srcimage,dstimg, CvType.CV_8UC1,1, 0);
19
20        //索贝尔垂直检测
21        Mat Sobel_dstimg=new Mat();
22       // Imgproc.Sobel(srcimage, dstimg, CvType.CV_8UC1,0, 1);
23
24        // Canny 边缘检测
25        Mat canny_dstimg=new Mat();
26        Imgproc.Canny(srcimage,canny_dstimg,50,240);
27
28        //拉普拉斯边检测
29        Mat laplacian_dstimg=new Mat();
30        Imgproc.Laplacian(srcimage,laplacian_dstimg,CvType.CV_8UC1);
31
32        HighGui.imshow("边缘检测 原图像",srcimage);
33        HighGui.imshow("边缘检测 Canny输出图像",canny_dstimg);
34        HighGui.imshow("边缘检测 Laplacian输出图像",laplacian_dstimg);
35        // 无限等待按键按下
36        HighGui.waitKey(0);
37    }
38}

2． 用OpenCV验证Hough变换检测图像中的直线或圆

1package com.gitee.dgw.lesson9;
2
3import com.gitee.dgw.lesson1.platformUtils;
4import org.opencv.core.Mat;
5import org.opencv.core.Point;
6import org.opencv.core.Scalar;
7import org.opencv.highgui.HighGui;
8import org.opencv.imgcodecs.Imgcodecs;
9import org.opencv.imgproc.Imgproc;
10
11
12
13/**
14 * @program: learn-opencv
15 * @description:
16 * @author: Mr.Dai
17 * @create: 2020-04-10 22:01
18 **/
19public class HoughDetect {
20
21    private final  static String path=System.getProperty("user.dir")+"\\line.png";
22    static{
23        platformUtils.loadLibraries();
24    }
25    public static void main(String[] args) {
26
27        Mat srcimage;
28        //读取一张灰度图片
29        srcimage= Imgcodecs.imread(path,Imgcodecs.IMREAD_COLOR);
30        if (srcimage.empty()) {
31            System.err.println("加载图片出错，请检查图片路径！");
32            return;
33        }
34        System.out.println(srcimage);
35        Mat dst_img=srcimage.clone();
36        Imgproc.Canny(srcimage, dst_img, 200, 500, 5, false);
37
38        Imgproc.cvtColor(srcimage,dst_img,Imgproc.COLOR_RGB2GRAY);
39        //dectCircle(srcimage, dst_img);
40        Mat storage = new Mat();
41        Imgproc.HoughLinesP(dst_img, storage, 1, Math.PI / 180, 50, 0, 0);
42        for (int x = 0; x < storage.rows(); x++)
43        {
44            double[] vec = storage.get(x, 0);
45            double x1 = vec[0], y1 = vec[1], x2 = vec[2], y2 = vec[3];
46            Point start = new Point(x1, y1);
47            Point end = new Point(x2, y2);
48            Imgproc.line(srcimage, start, end, new Scalar(0, 0, 255, 255), 1, Imgproc.LINE_4, 0);
49        }
50        HighGui.imshow("边缘检测 原图像",dst_img);
51        HighGui.imshow("边缘检测 Canny输出图像",srcimage);
52        // 无限等待按键按下
53        HighGui.waitKey(0);
54    }
55
56    private static void dectCircle(Mat srcimage, Mat dst_img) {
57        Mat circles = new Mat();
58        Imgproc.HoughCircles(dst_img, circles, Imgproc.HOUGH_GRADIENT, 1, 100, 440, 50, 0, 345);
59        //概率霍夫变换）
60        for (int i = 0; i < circles.cols(); i++)
61        {
62            double[] vCircle = circles.get(0, i);
63            Point center = new Point(vCircle[0], vCircle[1]);
64            int radius = (int) Math.round(vCircle[2]);
65            // circle center
66            Imgproc.circle(srcimage, center, 3, new Scalar(0, 255, 0), -1, 8, 0);
67            // circle outline
68            Imgproc.circle(srcimage, center, radius, new Scalar(0, 0, 255), 3, 8, 0);
69        }
70    }
71}