如何在javacv中识别和填充我的形状轮廓？

Question

我正在 javacv 上开发项目，我需要知道如何识别以下图像并使用特定颜色填充该图像？

我尝试浏览这个question，这是我使用的图像

我尝试浏览这段代码，并在 javacv 中开发了一个代码

import com.googlecode.javacpp.Loader;
import com.googlecode.javacv.CanvasFrame;
import static com.googlecode.javacpp.Loader.*;
import static com.googlecode.javacv.cpp.opencv_core.*;
import static com.googlecode.javacv.cpp.opencv_highgui.*;
import static com.googlecode.javacv.cpp.opencv_imgproc.*;
import java.io.File;
import javax.swing.JFileChooser;

public class PolyGonIdentification {
    public static void main(String[] args) {
        CanvasFrame cnvs=new CanvasFrame("Polygon");
        cnvs.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);

        CvMemStorage storage=CvMemStorage.create();
        CvSeq squares = new CvContour();
        squares = cvCreateSeq(0, sizeof(CvContour.class), sizeof(CvSeq.class), storage);
        JFileChooser f=new JFileChooser();
        int result=f.showOpenDialog(f);//show dialog box to choose files
        File myfile=null;
        String path="";
        if(result==0){
            myfile=f.getSelectedFile();//selected file taken to myfile
            path=myfile.getAbsolutePath();//get the path of the file
        }
        IplImage src = cvLoadImage(path);//hear path is actual path to image
        IplImage gry=cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,1);
        cvCvtColor(src, gry, CV_BGR2GRAY);
        cvThreshold(gry, gry, 230, 255, CV_THRESH_BINARY_INV);
        cvFindContours(gry, storage, squares, Loader.sizeof(CvContour.class),    CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE);
        System.out.println(squares.total());
        for (int i=0; i<squares.total(); i++)
        {
            cvDrawContours(gry, squares, CvScalar.ONE, CvScalar.ONE, 127, 1, 8);
        }
        IplConvKernel mat=cvCreateStructuringElementEx(7, 7, 3, 3, CV_SHAPE_RECT,    null);
        cvDilate(gry, gry, mat, CV_C);
        cvErode(gry, gry, mat, CV_C);
        cnvs.showImage(gry);

    }
}

我的最终结果应该是这样的图片

上面的代码生成了这种图像。请问有人可以帮我解决这个问题吗？

Answer 1

您可以使用此代码存档

    import com.googlecode.javacpp.Loader;
    import com.googlecode.javacv.CanvasFrame;
    import static com.googlecode.javacpp.Loader.*;
    import static com.googlecode.javacv.cpp.opencv_core.*;
    import static com.googlecode.javacv.cpp.opencv_highgui.*;
    import static com.googlecode.javacv.cpp.opencv_imgproc.*;
    import java.io.File;
    import javax.swing.JFileChooser;

    public class Ishape {
        public static void main(String[] args) {
            CanvasFrame cnvs=new CanvasFrame("Polygon");
            cnvs.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);

            CvMemStorage storage=CvMemStorage.create();
            CvSeq squares = new CvContour();
            squares = cvCreateSeq(0, sizeof(CvContour.class), sizeof(CvSeq.class), storage);
            JFileChooser f=new JFileChooser();
            int result=f.showOpenDialog(f);//show dialog box to choose files
                File myfile=null;
                String path="";
            if(result==0){
                myfile=f.getSelectedFile();//selected file taken to myfile
                path=myfile.getAbsolutePath();//get the path of the file
            }
            IplImage src = cvLoadImage(path);//hear path is actual path to image
            IplImage gry=cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,1);
            cvCvtColor(src, gry, CV_BGR2GRAY);
            cvThreshold(gry, gry, 230, 255, CV_THRESH_BINARY_INV);
            cvFindContours(gry, storage, squares, Loader.sizeof(CvContour.class), CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE);
            CvSeq ss=null;
            for (int i=0; i<1; i++)
            {
                cvDrawContours(gry, squares, CvScalar.WHITE, CV_RGB(248, 18, 18), 1, -1, 8);
                ss=cvApproxPoly(squares, sizeof(CvContour.class), storage, CV_POLY_APPROX_DP, 8, 0);
            }
            IplConvKernel mat=cvCreateStructuringElementEx(7, 7, 3, 3, CV_SHAPE_RECT, null);
            cvDilate(gry, gry, mat, CV_C);
            cvErode(gry, gry, mat, CV_C);
            cnvs.showImage(gry);

        }
    }

结果

这将被输出，我相信这可能会帮助您解决问题。

Answer 2

您只需要使用外部检索模式查找轮廓：

CV_RETR_EXTERNAL retrives only the extreme outer contours

在您的情况下，这是最好的模式，因为您有一个外部轮廓，而这个轮廓正是您要寻找的。 Here's 文档。

在此之后，只需使用drawContours 和CV_FILLED 作为厚度参数绘制它以填充外部多边形。

Answer 3

代码完全按照预期执行：

// as stated [in the answer to your previous question][1], findContours leaves gry set to 0, or black
cvFindContours(gry, storage, squares, Loader.sizeof(CvContour.class),   
         CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE); 

    System.out.println(squares.total()); // nothing interesting

    for (int i = 0; i < squares.total(); i++)
    {
        // draw a gray contour (127) on a black image
        cvDrawContours(gry, squares, CvScalar.ONE, CvScalar.ONE, 127, 1, 8);
    }

要更正它，您必须将 gry 设置为 255（白色，在调用 drawContours 之前绘制黑色轮廓！即 0，而不是 127。）