Question

我正在尝试从手机的相机拍摄照片，然后将其传递给tesseract引擎，并通过您在下面看到的代码将结果写在文本视图中。

MainActivity：

package com.example.arbazalam.myapplication;

import android.Manifest;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.MediaStore;
import android.speech.tts.TextToSpeech;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {

    private MyTessOCR mTessOCR = new MyTessOCR(MainActivity.this);

    private Button takePictureButton;
    private ImageView imageView;

    int TAKE_PHOTO_CODE = 0;
    public static int count = 0;

    private TextView resultText;


    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mTessOCR = new MyTessOCR(MainActivity.this);

        resultText = findViewById(R.id.textView_result);

        if (checkPermissions()){
            //  permissions  granted.

        }

        final String dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + "/picFolder/";
        final File newdir = new File(dir);
        newdir.mkdirs();

        Button capture = findViewById(R.id.btnCapture);
        capture.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {

                count++;
                String file = dir+count+".jpg";
                File newfile = new File(file);
                try {
                    newfile.createNewFile();

                    Bitmap bitmap = BitmapFactory.decodeFile(file);
                    doOCR(bitmap);


                }
                catch (IOException e)
                {
                }

                Uri outputFileUri = FileProvider.getUriForFile(MainActivity.this, BuildConfig.APPLICATION_ID, newfile);

                Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);

                startActivityForResult(cameraIntent, TAKE_PHOTO_CODE);
            }
        });


    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data)
    {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == TAKE_PHOTO_CODE && resultCode == RESULT_OK) {
            Log.d("CameraDemo", "Pic saved");
        }
    }





    public static final int MULTIPLE_PERMISSIONS = 10;

    String[] permissions= new String[]{
            Manifest.permission.WRITE_EXTERNAL_STORAGE,
            Manifest.permission.CAMERA};
         //   Manifest.permission.ACCESS_COARSE_LOCATION,
          //  Manifest.permission.ACCESS_FINE_LOCATION};




    private  boolean checkPermissions() {
        int result;
        List<String> listPermissionsNeeded = new ArrayList<>();
        for (String p:permissions) {
            result = ContextCompat.checkSelfPermission(MainActivity.this,p);
            if (result != PackageManager.PERMISSION_GRANTED) {
                listPermissionsNeeded.add(p);
            }
        }
        if (!listPermissionsNeeded.isEmpty()) {
            ActivityCompat.requestPermissions(this, listPermissionsNeeded
                    .toArray(new String[listPermissionsNeeded.size()]),MULTIPLE_PERMISSIONS );
            return false;
        }
        return true;
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
            case MULTIPLE_PERMISSIONS:{
                if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                    // permissions granted.
                } else {
                    Toast.makeText(this, "Go to settings and enable permissions", Toast.LENGTH_LONG)
                            .show();
                    }
                    // permissions list of don't granted permission
                }
                return;
            }
        }



    private void doOCR(final Bitmap bitmap2) {
        String text = mTessOCR.getOCRResult(bitmap2);
        resultText.setText(text);

    }
}

MyTessOCR：

package com.example.arbazalam.myapplication;


import android.content.Context;
import android.content.res.AssetManager;
import android.graphics.Bitmap;
import android.os.Environment;
import android.util.Log;

import com.googlecode.tesseract.android.TessBaseAPI;

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;

public class MyTessOCR {
    private String datapath;
    private TessBaseAPI mTess;
    public Context context;

    public MyTessOCR(Context context)
    {
        this.context = context;
        datapath = Environment.getExternalStorageDirectory() + "/ocrctz/";
        File dir = new File(datapath + "/tessdata/");
        File file = new File(datapath + "/tessdata/" + "eng.traineddata");
        if (!file.exists())
        {
            Log.d("mylog", "in file doesn't exist");
            dir.mkdirs();
            copyFile(context);
        }

        mTess = new TessBaseAPI();
        String language = "eng";
        mTess.init(datapath, language);
        //Auto only
        mTess.setPageSegMode(TessBaseAPI.PageSegMode.PSM_AUTO_ONLY);
    }

    public void stopRecognition() {
        mTess.stop();
    }

    public String getOCRResult(Bitmap bitmap)
    {
        mTess.setImage(bitmap);
        String detected = mTess.getUTF8Text();
        return detected;
    }

    public void onDestroy()
    {
        if (mTess != null)
            mTess.end();
    }

    private void copyFile(Context context)
    {
        AssetManager assetManager = context.getAssets();
        try
        {   InputStream in = assetManager.open("eng.traineddata");
            OutputStream out = new FileOutputStream(datapath + "/tessdata/" + "eng.traineddata");
            byte[] buffer = new byte[1024];
            int read = in.read(buffer);
            while (read != -1) {
                out.write(buffer, 0, read);
                read = in.read(buffer);            }
        } catch (Exception e)
        {
            Log.d("mylog", "couldn't copy with the following error : "+e.toString());
        }
    }
}

但我收到此错误消息：

java.lang.RuntimeException: Failed to read bitmap

在这行代码中：

mTess.setImage(bitmap);

为什么会发生这种情况，我该如何解决？我使用Windows 10和android studio 3.0.1与API 27和min API 21。

Answer 1

此错误的原因是位图必须为非空或位图配置必须为ARGB_8888或无法从位图读取像素

mTess.setImage（bitmap）;代码是

public

ReadFile.readBitmap（bmp）;代码是

public void setImage(Bitmap bmp) {
    if (mRecycled)
        throw new IllegalStateException();

    Pix image = ReadFile.readBitmap(bmp);

    if (image == null) {
        throw new RuntimeException("Failed to read bitmap");//Here's the log printed.
    }

    nativeSetImagePix(mNativeData, image.getNativePix());

    image.recycle();
}

我犯了一个错误，因为位图配置是RGB_565。

java.lang.RuntimeException：无法读取位图

1 个答案: