OCR需要API

Question

我正在开展OCR项目，但我遇到了TessBase API的问题; 首先，我不确切知道这个API究竟是什么以及为什么要使用它，尽管我编写的代码是在搜索时看到但仍然有错误

在那里，我必须将它作为一个lib包含在我的项目中

public void executeOCR() {

    ***TessBaseAPI baseApi = new TessBaseAPI();***
    baseApi.setDebug(true);

    baseApi.init(DATA_PATH, "eng");

    Bitmap bmps = croppedBmp.copy(Bitmap.Config.ARGB_8888, true);

    baseApi.setImage(bmps);

    String recognizedText = baseApi.getUTF8Text();

    baseApi.end();

    // Toast.makeText(Crop_Activity.this, recognizedText, Toast.LENGTH_LONG)
    // .show();

    resultEditText.setText(recognizedText);
}

错误完全在粗线上：

    ***TessBaseAPI baseApi = new TessBaseAPI();***





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

import android.app.Activity;
import android.content.Intent;
import android.content.res.AssetManager;
import android.graphics.Bitmap;
import android.graphics.PointF;
import android.graphics.drawable.BitmapDrawable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.Toast;

import com.googlecode.tesseract.android.TessBaseAPI;

public class Crop_Activity extends Activity {

    Bitmap bmp;

    RelativeLayout outerLayout, rectLayout;
    ImageView originalImage;
    Button captureButton, cropButton, sendButton, addButton;
    EditText resultEditText;
    PointF startpoint, endpoint;
    Button translate;

    String storage_path = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        storage_path = Environment.getExternalStorageDirectory().toString()
                + "/SimpleAndroidOCR/";

        createDirectories();

        if (!(new File(storage_path + "tessdata/eng.traineddata")).exists()) {
            try {
                AssetManager assetManager = getAssets();

                InputStream in = assetManager.open("Files/eng.traineddata.mp3");

                OutputStream out = new FileOutputStream(storage_path
                        + "tessdata/eng.traineddata");

                byte[] buf = new byte[1024];
                int len;

                while ((len = in.read(buf)) > 0) {
                    out.write(buf, 0, len);
                }

                in.close();
                out.close();

            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        super.onCreate(savedInstanceState);
        setContentView(R.layout.crop_image_layout);
        // requestWindowFeature(Window.FEATURE_NO_TITLE);

        outerLayout = (RelativeLayout) findViewById(R.id.outerLayout);
        rectLayout = (RelativeLayout) findViewById(R.id.rect_relativeLayout);

        originalImage = (ImageView) findViewById(R.id.origional_image);

        captureButton = (Button) findViewById(R.id.captureButton);
        captureButton.setOnClickListener(captureButton_onClick);

        cropButton = (Button) findViewById(R.id.cropButton);
        cropButton.setOnClickListener(cropButton_onClick);

        addButton = (Button) findViewById(R.id.addButton);
        addButton.setOnClickListener(addButton_onClick);

        rectLayout.bringToFront();

        outerLayout.setOnTouchListener(new MyListener());
        outerLayout.setOnClickListener(new MyListener());

        resultEditText = (EditText) findViewById(R.id.resultEditText);

        translate = (Button) findViewById(R.id.transbtn);
        translate.setOnClickListener(translate_onClick);
    }

    private void createDirectories() {

        String[] paths = new String[] { storage_path,
                storage_path + "tessdata/" };

        for (String path : paths) {
            File dir = new File(path);
            if (!dir.exists()) {
                if (!dir.mkdirs()) {
                    return;
                }
            }
        }
    }

    String DATA_PATH = "/mnt/sdcard/SimpleAndroidOCR/";

    public void executeOCR() {
        TessBaseAPI baseApi = new TessBaseAPI();
        baseApi.setDebug(true);

        baseApi.init(DATA_PATH, "eng");

        Bitmap bmps = croppedBmp.copy(Bitmap.Config.ARGB_8888, true);

        baseApi.setImage(bmps);

        String recognizedText = baseApi.getUTF8Text();

        baseApi.end();

        // Toast.makeText(Crop_Activity.this, recognizedText, Toast.LENGTH_LONG)
        // .show();

        resultEditText.setText(recognizedText);
    }

    View.OnClickListener cropButton_onClick = new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            setCroppedImage();

            executeOCR();
        }
    };

    View.OnClickListener captureButton_onClick = new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            Intent i = new Intent(
                    android.provider.MediaStore.ACTION_IMAGE_CAPTURE);

            startActivityForResult(i, 0);
        }
    };

    View.OnClickListener addButton_onClick = new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            if (!resultEditText.getText().toString().equals("")) {
                SharedData.result.add(resultEditText.getText().toString());

                Toast.makeText(Crop_Activity.this, "Data added",
                        Toast.LENGTH_SHORT).show();
            }
        }
    };

    // View.OnClickListener sendButton_onClick = new View.OnClickListener() {
    //
    // @Override
    // public void onClick(View v) {
    //
    // Intent i = new Intent(Crop_Activity.this, SendActivity.class);
    //
    // startActivity(i);
    // }
    // };

    public static void launchGoogleTranslateApp(Activity activity) {

    }

    View.OnClickListener translate_onClick = new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            // Intent LaunchIntent = getPackageManager()
            // .getLaunchIntentForPackage(
            // "com.google.android.apps.translate");
            Intent LanuchIntent = new Intent();

            startActivity(LanuchIntent);

        }
    };

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

        if (resultCode == RESULT_OK) {
            Bundle extras = data.getExtras();

            bmp = (Bitmap) extras.get("data");

            originalImage.setImageBitmap(bmp);
        }
    }

    public void updateRect() {
        int left = (int) Math.min(startpoint.x, endpoint.x);
        int right = (int) Math.max(startpoint.x, endpoint.x);
        int top = (int) Math.min(startpoint.y, endpoint.y);
        int bottom = (int) Math.max(startpoint.y, endpoint.y);

        RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(right
                - left, bottom - top);

        lp.leftMargin = left;
        lp.topMargin = top;

        rectLayout.setLayoutParams(lp);
    }

    Bitmap croppedBmp;

    public void setCroppedImage() {

        try {
            Bitmap origionalBitmap = ((BitmapDrawable) originalImage
                    .getDrawable()).getBitmap();

            double w = originalImage.getWidth();
            double h = originalImage.getHeight();

            double xFactor = origionalBitmap.getWidth() / w;
            double yFactor = origionalBitmap.getHeight() / h;

            int left = (int) Math.min(startpoint.x, endpoint.x);
            int right = (int) Math.max(startpoint.x, endpoint.x);
            int top = (int) Math.min(startpoint.y, endpoint.y);
            int bottom = (int) Math.max(startpoint.y, endpoint.y);

            croppedBmp = Bitmap.createBitmap(origionalBitmap,
                    (int) (left * xFactor), (int) (top * yFactor),
                    (int) (right * xFactor) - (int) (left * xFactor),
                    (int) (bottom * yFactor) - (int) (top * yFactor));

        } catch (Exception e) {
            e.printStackTrace();

            Toast.makeText(Crop_Activity.this, "Error in Crop",
                    Toast.LENGTH_LONG).show();
        }
    }

    class MyListener implements OnTouchListener, View.OnClickListener {

        public boolean onTouch(View v, MotionEvent e) {
            if (e.getAction() == MotionEvent.ACTION_MOVE) {
                endpoint = new PointF(e.getX(), e.getY());
                updateRect();
            } else if (e.getAction() == MotionEvent.ACTION_DOWN) {
                startpoint = new PointF(e.getX(), e.getY());
                RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(
                        0, 0);
                rectLayout.setLayoutParams(lp);
            } else if (e.getAction() == MotionEvent.ACTION_UP) {
                endpoint = new PointF(e.getX(), e.getY());
                updateRect();
                cropButton.setEnabled(true);
            }

            return false;
        }

        public void onClick(View v) {
        }
    }

    class getTextFromImage extends AsyncTask<String, String, String> {

        protected String doInBackground(String... arg0) {

            try {
                executeOCR();
            } catch (Exception e) {
                e.printStackTrace();

                Toast.makeText(Crop_Activity.this, "Error in OCR",
                        Toast.LENGTH_LONG).show();
            }

            return null;
        }

        @Override
        protected void onPostExecute(String result) {

        }
    }

}

Answer 1

TessBaseApi是一类用于执行OCR的tesseract api。你可以在这个github repo上找到适用于Android的库的端口https://github.com/rmtheis/tess-two它很容易导入你的proyect你可以找到回购中的指令。