如何绘制箭头并实时显示在边框上？

Question

我需要创建四个箭头（上、下、左、右）并将它们真实地放在框架上 time.I 我正在做一些实时图像处理工作，并基于我需要的功能的结果在框架上实时显示箭头。从以下位置获取帧后：

 public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {

    mRgba = inputFrame.rgba();
    mGray = inputFrame.gray();
    if(state){

        myTask= new MyTask();
        myTask.execute(mRgba);
        //need to write method to display arrow
        return mRgba;
    }
    return mRgba;
}

它调用异步任务来识别和设置需要哪个箭头的方法 displayed.For 现在它 return 1 如果开始帧和其他帧是 same.I 需要知道的如何制作箭头并将其显示在 frame.I 上稍后将制定一个算法来阻止方向，因此让我们假设当 return 为 1 时我需要在框架中显示向上箭头。我的异步任务是：

class MyTask extends AsyncTask<Mat, Void, Integer> {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected Integer doInBackground(Mat... mats) {
        if(!isCancelled())
        return recognize(mats[0]);
        else return 0;
    }

    @Override
    protected void onPostExecute(Integer integer) {
        super.onPostExecute(integer);
        directionOfCamera=integer;
    }

    @Override
    protected void onCancelled() {
        super.onCancelled();
    }
}

识别的方法是：

public int recognize(Mat inputFrame) {

    if (startedFrame){

        deskriptor.detect(inputFrame,keypoints1);
        deskriptor.compute(inputFrame,keypoints1,deskriptor1);

        startedFrame=false;
        return 0;
    }

    deskriptor.detect(inputFrame,keypoints2);

    Size size;
    size=keypoints2.size();

    if(size.height!= 0) {
    deskriptor.compute(inputFrame,keypoints2,deskriptor2);

    List<MatOfDMatch> matches = new LinkedList<MatOfDMatch>();

    matcher.knnMatch(deskriptor1, deskriptor2, matches,2);

        //Calculating good match list...
        LinkedList<DMatch> goodMatchesList = new LinkedList<DMatch>();

        for (int i = 0; i < matches.size(); i++) {
            MatOfDMatch matofDMatch = matches.get(i);
            DMatch[] dmatcharray = matofDMatch.toArray();
            DMatch m1 = dmatcharray[0];
            DMatch m2 = dmatcharray[1];

            if (m1.distance <= m2.distance * nndrRatio) {
                goodMatchesList.addLast(m1);

            }
        }

        if (goodMatchesList.size() >= 7) {

            List<KeyPoint> controlKeypointlist = keypoints1.toList();
            List<KeyPoint> liveKeypointlist = keypoints2.toList();

            LinkedList<Point> objectPoints = new LinkedList<>();
            LinkedList<Point> scenePoints = new LinkedList<>();

            for (int i = 0; i < goodMatchesList.size(); i++) {
                objectPoints.addLast(controlKeypointlist.get(goodMatchesList.get(i).queryIdx).pt);
                scenePoints.addLast(liveKeypointlist.get(goodMatchesList.get(i).trainIdx).pt);
            }

            MatOfPoint2f objMatOfPoint2f = new MatOfPoint2f();
            objMatOfPoint2f.fromList(objectPoints);

            MatOfPoint2f scnMatOfPoint2f = new MatOfPoint2f();
            scnMatOfPoint2f.fromList(scenePoints);

            return 1;

        }
    }

    return 0;
}

基本上应该是这样的：

如果缺少任何有帮助的代码，请告诉我，我会添加。

Answer 1

作为解决方案 - 在 Adobe After Effects 中绘制箭头并使用这个AirBnB library来实现它

如何绘制箭头并实时显示在边框上？

How to draw an arrow,put on frame and display in real time?

java

android

android-xml

android-drawable