JAVA CODE:
B4X:
package com.tuts.prakash.simpleocr;
import android.Manifest;
import android.content.pm.PackageManager;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.util.SparseArray;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.widget.TextView;
import com.google.android.gms.vision.CameraSource;
import com.google.android.gms.vision.Detector;
import com.google.android.gms.vision.text.TextBlock;
import com.google.android.gms.vision.text.TextRecognizer;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {
SurfaceView mCameraView;
TextView mTextView;
CameraSource mCameraSource;
private static final String TAG = "MainActivity";
private static final int requestPermissionID = 101;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mCameraView = findViewById(R.id.surfaceView);
mTextView = findViewById(R.id.text_view);
startCameraSource();
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
if (requestCode != requestPermissionID) {
Log.d(TAG, "Got unexpected permission result: " + requestCode);
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
return;
}
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
try {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
return;
}
mCameraSource.start(mCameraView.getHolder());
} catch (IOException e) {
e.printStackTrace();
}
}
}
private void startCameraSource() {
//Create the TextRecognizer
final TextRecognizer textRecognizer = new TextRecognizer.Builder(getApplicationContext()).build();
if (!textRecognizer.isOperational()) {
Log.w(TAG, "Detector dependencies not loaded yet");
} else {
//Initialize camerasource to use high resolution and set Autofocus on.
mCameraSource = new CameraSource.Builder(getApplicationContext(), textRecognizer)
.setFacing(CameraSource.CAMERA_FACING_BACK)
.setRequestedPreviewSize(1280, 1024)
.setAutoFocusEnabled(true)
.setRequestedFps(2.0f)
.build();
/**
* Add call back to SurfaceView and check if camera permission is granted.
* If permission is granted we can start our cameraSource and pass it to surfaceView
*/
mCameraView.getHolder().addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
if (ActivityCompat.checkSelfPermission(getApplicationContext(),
Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.CAMERA},
requestPermissionID);
return;
}
mCameraSource.start(mCameraView.getHolder());
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
mCameraSource.stop();
}
});
//Set the TextRecognizer's Processor.
textRecognizer.setProcessor(new Detector.Processor<TextBlock>() {
@Override
public void release() {
}
/**
* Detect all the text from camera using TextBlock and the values into a stringBuilder
* which will then be set to the textView.
* */
@Override
public void receiveDetections(Detector.Detections<TextBlock> detections) {
final SparseArray<TextBlock> items = detections.getDetectedItems();
if (items.size() != 0 ){
mTextView.post(new Runnable() {
@Override
public void run() {
StringBuilder stringBuilder = new StringBuilder();
for(int i=0;i<items.size();i++){
TextBlock item = items.valueAt(i);
stringBuilder.append(item.getValue());
stringBuilder.append("\n");
}
mTextView.setText(stringBuilder.toString());
}
});
}
}
});
}
}
}