Android studioを用いたOpenCVでの色、文字認識

前提・実現したいこと

今openCVを用いて色認識、文字認識、図形認識を行うプログラムを作成しているのですが、
とあるサイト内にあった”四角形を認識する方法”は実装したのですが、色認識、文字認識を実装するにあたり、
今使っているツールでの実例且つ先ほど述べた実装ソースに組み合わせやすい方法が見つかりません。
具体的でなくてもいいのでここであれをしたらいいのではということでも教えていただければと思います。

発生している問題・エラーメッセージ

適切な手段がわからない

該当のソースコード

java
1import android.content.Intent;
2import android.graphics.Bitmap;
3import android.os.Parcelable;
4import android.os.Bundle;
5import android.widget.ImageView;
6
7import androidx.appcompat.app.AppCompatActivity;
8
9import org.opencv.android.Utils;
10import org.opencv.core.Core;
11import org.opencv.core.CvType;
12import org.opencv.core.Mat;
13import org.opencv.core.MatOfPoint;
14import org.opencv.core.MatOfPoint2f;
15import org.opencv.core.Point;
16import org.opencv.core.Scalar;
17import org.opencv.core.Size;
18import org.opencv.imgproc.Imgproc;
19
20import java.util.ArrayList;
21import java.util.List;
22
23public class Seartchj extends AppCompatActivity {
24    static {
25        System.loadLibrary("opencv_java3");
26    }
27    Bitmap picture;
28    private  ImageView imageView2;
29    int youso[][]= new int[16][16];
30    @Override
31    protected void onCreate(Bundle savedInstanceState) {
32        //imageView = findViewById(R.id.image_vie);
33        super.onCreate(savedInstanceState);
34        setContentView(R.layout.activity_seartchj);
35        imageView2 = findViewById(R.id.image_vie);
36        Intent i= getIntent();
37        picture = (i!=null)? (Bitmap) i.getParcelableExtra("data") :null;
38        onImageScan();
39    }
40    private void onImageScan() {
41        Mat mat = new Mat();
42        Utils.bitmapToMat(picture, mat, false);
43        mat = getThreshold(mat);
44        List<MatOfPoint> contours = getContour(mat);
45        List<List<Point>> points = contour2point(contours);
46    }
47    private Mat getThreshold(Mat mat) {
48        Mat mat_rgb = mat.clone();
49       List<Mat> channels_rgb = new ArrayList<Mat>();
50        Core.split(mat_rgb, channels_rgb);
51        Imgproc.cvtColor(mat_rgb, mat_rgb, Imgproc.COLOR_RGB2GRAY);
52        Core.subtract(channels_rgb.get(0), mat_rgb, channels_rgb.get(0));
53        Core.subtract(channels_rgb.get(1), mat_rgb, channels_rgb.get(1));
54        Core.subtract(channels_rgb.get(2), mat_rgb, channels_rgb.get(2));
55        Imgproc.threshold(channels_rgb.get(0), channels_rgb.get(0), 0.0, 255.0, Imgproc.THRESH_BINARY | Imgproc.THRESH_OTSU);
56        Imgproc.threshold(channels_rgb.get(1), channels_rgb.get(1), 0.0, 255.0, Imgproc.THRESH_BINARY | Imgproc.THRESH_OTSU);
57        Imgproc.threshold(channels_rgb.get(2), channels_rgb.get(2), 0.0, 255.0, Imgproc.THRESH_BINARY | Imgproc.THRESH_OTSU);
58        List<MatOfPoint> contour_rgb0 = getContour(channels_rgb.get(0));
59        List<MatOfPoint> contour_rgb1 = getContour(channels_rgb.get(1));
60        List<MatOfPoint> contour_rgb2 = getContour(channels_rgb.get(2));
61        Mat mat_yuv = mat.clone();
62        Imgproc.cvtColor(mat_yuv, mat_yuv, Imgproc.COLOR_BGR2YUV);
63        List<Mat> channels_yuv = new ArrayList<Mat>();
64        Core.split(mat_yuv, channels_yuv);
65        Imgproc.cvtColor(mat_yuv, mat_yuv, Imgproc.COLOR_RGB2GRAY);
66        Core.subtract(channels_yuv.get(0), mat_yuv, channels_yuv.get(0));
67        Core.subtract(channels_yuv.get(1), mat_yuv, channels_yuv.get(1));
68        Core.subtract(channels_yuv.get(2), mat_yuv, channels_yuv.get(2));
69        Imgproc.threshold(channels_yuv.get(0), channels_yuv.get(0), 0.0, 255.0, Imgproc.THRESH_BINARY | Imgproc.THRESH_OTSU);
70        Imgproc.threshold(channels_yuv.get(1), channels_yuv.get(1), 0.0, 255.0, Imgproc.THRESH_BINARY_INV | Imgproc.THRESH_OTSU);
71        Imgproc.threshold(channels_yuv.get(2), channels_yuv.get(2), 0.0, 255.0, Imgproc.THRESH_BINARY_INV | Imgproc.THRESH_OTSU);
72        List<MatOfPoint> contour_yuv0 = getContour(channels_yuv.get(0));
73        List<MatOfPoint> contour_yuv1 = getContour(channels_yuv.get(1));
74        List<MatOfPoint> contour_yuv2 = getContour(channels_yuv.get(2));
75        Mat mat_mask = new Mat(mat.size(), CvType.CV_8UC4, Scalar.all(255));
76        Scalar color = new Scalar(0, 0, 0);
77        Imgproc.drawContours(mat_mask, contour_rgb0, -1, color, -1);
78        Imgproc.drawContours(mat_mask, contour_rgb1, -1, color, -1);
79        Imgproc.drawContours(mat_mask, contour_rgb2, -1, color, -1);
80        Imgproc.drawContours(mat_mask, contour_yuv0, -1, color, -1);
81        Imgproc.drawContours(mat_mask, contour_yuv1, -1, color, -1);
82        Imgproc.drawContours(mat_mask, contour_yuv2, -1, color, -1);
83        Imgproc.cvtColor(mat_mask, mat_mask, Imgproc.COLOR_RGB2GRAY);
84        Imgproc.threshold(mat_mask, mat_mask, 0.0, 255.0, Imgproc.THRESH_BINARY_INV | Imgproc.THRESH_OTSU);
85        return mat_mask;
86    }
87
88    private List<MatOfPoint> getContour(Mat mat) {
89        List<MatOfPoint> contour = new ArrayList<MatOfPoint>();
90        List<MatOfPoint> tmp_contours = new ArrayList<MatOfPoint>();
91        Mat hierarchy = Mat.zeros(new Size(5, 5), CvType.CV_8UC1);
92        Imgproc.findContours(mat, tmp_contours, hierarchy, Imgproc.RETR_EXTERNAL, Imgproc.CHAIN_APPROX_TC89_L1);
93        for (int i = 0; i < tmp_contours.size(); i++) {
94            if (Imgproc.contourArea(tmp_contours.get(i)) < mat.size().area() / (100 * 1)) {
95                continue;
96            }
97            MatOfPoint2f ptmat2 = new MatOfPoint2f(tmp_contours.get(i).toArray());
98            MatOfPoint2f approx = new MatOfPoint2f();
99            MatOfPoint approxf1 = new MatOfPoint();
100            double arclen = Imgproc.arcLength(ptmat2, true);
101            Imgproc.approxPolyDP(ptmat2, approx, 0.02 * arclen, true);
102            approx.convertTo(approxf1, CvType.CV_32S);
103            if (approxf1.size().area() != 3) {
104                youso[0][0]=1;
105            }else if(approxf1.size().area() !=4){
106                youso[1][0]=1;
107            }else if(approxf1.size().area() !=0){
108                youso[2][0]=1;
109            }else if(approxf1.size().area() !=5){
110                youso[3][0]=1;
111            }else if(approxf1.size().area() !=6){
112                youso[4][0]=1;
113            }
114            contour.add(approxf1);
115        }
116        return contour;
117    }
118
119    private List<List<Point>> contour2point(List<MatOfPoint> contour) {
120        List<List<Point>> points = new ArrayList<List<Point>>();
121        for(int i = 0; i < contour.size(); i++) {
122            points.add(contour.get(i).toList());
123        }
124        return points;
125    }
126    public  void sign(int c[][]){
127        if(c[0][0]==1&&c[0][1]==1){
128            //stop
129            imageView2.setImageResource(R.drawable.pen);
130        }else if(c[4][0]!=1){
131            //mitei
132        }
133    }
134
135}