我想检测采用了android圈。我成功地实现了检测线的算法，但没有试图绘制霍夫圈algoritm时被显示出来。

这是我的code：

 垫thresholdImage =新材料（getFrameHeight（）+ getFrameHeight（）/ 2，getFrameWidth（），CvType.CV_8UC1）;
            mYuv.put（0，0，数据）;
            Imgproc.cvtColor（mYuv，目的地，Imgproc.COLOR_YUV420sp2RGB，4）;
            Imgproc.cvtColor（目的地，thresholdImage，Imgproc.COLOR_RGB2GRAY，4）;
            Imgproc.GaussianBlur（thresholdImage，thresholdImage，新尺寸（9,9），2,2）;

        垫圈=新垫（）;


        Imgproc.HoughCircles（thresholdImage，圆，Imgproc.CV_HOUGH_GRADIENT，1D，（双）thresholdImage.height（）/ 70，200D，100D）;

        Log.w（圈子，circles.cols（）+）;
        为（中间体X = 0 X  - 其中; circles.cols（）; X ++）
        {
                双vCircle [] = circles.get（0，x）的;

                点中心=新的点（Math.round（vCircle [0]），Math.round（vCircle [1]））;
                INT半径=（int）的Math.round（vCircle [2]）;
                //绘制圆心
                Core.circle（目的地，中心，3个，新标量（0,255,0），-1，8,0）;
                //绘制圆形轮廓
                Core.circle（目的地，圆心，半径，新的标量（0,0,255），3，8，0）;

        }
 

解决方案

您可能会得到这个排序了，但几件事情。我会检查你的社交圈垫实际上有一定的效果;有时vCircle似乎又回来了空;尝试其他版本HoughCircles之一：

  iCannyUpperThreshold = 100;
iMinRadius = 20;
iMaxRadius = 400;
iAccumulator = 300;

Imgproc.HoughCircles（thresholdImage，圆，Imgproc.CV_HOUGH_GRADIENT，
         2.0，thresholdImage.rows（）/ 8，iCannyUpperThreshold，iAccumulator，
         iMinRadius，iMaxRadius）;

如果（circles.cols（）大于0）
    为（中间体X = 0 X  - 其中; circles.cols（）; X ++）
        {
        双vCircle [] = circles.get（0，x）的;

        如果（vCircle == NULL）
            打破;

        点PT =新的点（Math.round（vCircle [0]），Math.round（vCircle [1]））;
        INT半径=（int）的Math.round（vCircle [2]）;

        //绘制发现圈
        Core.circle（目的地，PT，半径，新的标量（0,255,0），iLineThickness）;
        Core.circle（目的地，PT，3，新的标量（0,0,255），iLineThickness）;
        }
 

（我换你的code到煤矿，改名为一些东西，换回来的，我的认为的我得回去，这样它的作品...）

乙。

I am trying to detect circles using android. I succeeded to implement the detect lines algorithm but nothing gets displayed when trying the draw hough circles algoritm.

Here is my code:

Mat thresholdImage = new Mat(getFrameHeight() + getFrameHeight() / 2, getFrameWidth(), CvType.CV_8UC1);
            mYuv.put(0, 0, data);
            Imgproc.cvtColor(mYuv, destination, Imgproc.COLOR_YUV420sp2RGB, 4);
            Imgproc.cvtColor(destination, thresholdImage, Imgproc.COLOR_RGB2GRAY, 4);
            Imgproc.GaussianBlur(thresholdImage, thresholdImage, new Size(9, 9), 2, 2 );

        Mat circles = new Mat();


        Imgproc.HoughCircles(thresholdImage, circles, Imgproc.CV_HOUGH_GRADIENT, 1d, (double)thresholdImage.height()/70, 200d, 100d);

        Log.w("circles", circles.cols()+"");
        for (int x = 0; x < circles.cols(); x++) 
        {
                double vCircle[]=circles.get(0,x);

                Point center=new Point(Math.round(vCircle[0]), Math.round(vCircle[1]));
                int radius = (int)Math.round(vCircle[2]);
                // draw the circle center
                Core.circle(destination, center, 3,new Scalar(0,255,0), -1, 8, 0 );
                // draw the circle outline
                Core.circle( destination, center, radius, new Scalar(0,0,255), 3, 8, 0 );

        }

You may have got this sorted by now, but a few things. I'd check your circles mat actually has some results; sometimes vCircle seems to come back null; try one of the other versions of HoughCircles:

iCannyUpperThreshold = 100;
iMinRadius = 20;
iMaxRadius = 400;
iAccumulator = 300;

Imgproc.HoughCircles(thresholdImage, circles, Imgproc.CV_HOUGH_GRADIENT, 
         2.0, thresholdImage.rows() / 8, iCannyUpperThreshold, iAccumulator, 
         iMinRadius, iMaxRadius);

if (circles.cols() > 0)
    for (int x = 0; x < circles.cols(); x++) 
        {
        double vCircle[] = circles.get(0,x);

        if (vCircle == null)
            break;

        Point pt = new Point(Math.round(vCircle[0]), Math.round(vCircle[1]));
        int radius = (int)Math.round(vCircle[2]);

        // draw the found circle
        Core.circle(destination, pt, radius, new Scalar(0,255,0), iLineThickness);
        Core.circle(destination, pt, 3, new Scalar(0,0,255), iLineThickness);
        }

(I swapped your code into mine, renamed some stuff and swapped it back, I think I've got it back so it works...)

B.