所以，我在android studio中开发具有明显的图像到文本功能的OCR应用程序。我在编码时认为自己是菜鸟。现在，我正在关注this教程，我对我所遵循的其他教程的结果非常满意。但是，有一个问题，我想在应用程序中或在拍摄照片后为应用程序添加裁剪功能。最好的选择是在相机屏幕上绘制一个矩形，用户可以根据所需的文本更改尺寸。但是，我不想更改代码中的任何内容，因为它完美地工作。有人可以帮忙吗？
这是MainActivity.java
public class MainActivity extends AppCompatActivity {
private static final String LOG_TAG = "Text API";
private static final int PHOTO_REQUEST = 10;
private TextView scanResults;
private Uri imageUri;
private TextRecognizer detector;
private static final int REQUEST_WRITE_PERMISSION = 20;
private static final String SAVED_INSTANCE_URI = "uri";
private static final String SAVED_INSTANCE_RESULT = "result";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button = (Button) findViewById(R.id.button);
scanResults = (TextView) findViewById(R.id.results);
if (savedInstanceState != null) {
imageUri = Uri.parse(savedInstanceState.getString(SAVED_INSTANCE_URI));
scanResults.setText(savedInstanceState.getString(SAVED_INSTANCE_RESULT));
}
detector = new TextRecognizer.Builder(getApplicationContext()).build();
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
ActivityCompat.requestPermissions(MainActivity.this, new
String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_WRITE_PERMISSION);
}
});
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case REQUEST_WRITE_PERMISSION:
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
takePicture();
} else {
Toast.makeText(MainActivity.this, "Permission Denied!", Toast.LENGTH_SHORT).show();
}
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == PHOTO_REQUEST && resultCode == RESULT_OK) {
launchMediaScanIntent();
try {
Bitmap bitmap = decodeBitmapUri(this, imageUri);
if (detector.isOperational() && bitmap != null) {
Frame frame = new Frame.Builder().setBitmap(bitmap).build();
SparseArray<TextBlock> textBlocks = detector.detect(frame);
String blocks = "";
String lines = "";
String words = "";
for (int index = 0; index < textBlocks.size(); index++) {
//extract scanned text blocks here
TextBlock tBlock = textBlocks.valueAt(index);
blocks = blocks + tBlock.getValue() + "\n" + "\n";
for (Text line : tBlock.getComponents()) {
//extract scanned text lines here
lines = lines + line.getValue() + "\n";
for (Text element : line.getComponents()) {
//extract scanned text words here
words = words + element.getValue() + ", ";
}
}
}
if (textBlocks.size() == 0) {
scanResults.setText("Scan Failed: Found nothing to scan");
} else {
scanResults.setText(scanResults.getText() + "Blocks: " + "\n");
scanResults.setText(scanResults.getText() + blocks + "\n");
scanResults.setText(scanResults.getText() + "---------" + "\n");
scanResults.setText(scanResults.getText() + "Lines: " + "\n");
scanResults.setText(scanResults.getText() + lines + "\n");
scanResults.setText(scanResults.getText() + "---------" + "\n");
scanResults.setText(scanResults.getText() + "Words: " + "\n");
scanResults.setText(scanResults.getText() + words + "\n");
scanResults.setText(scanResults.getText() + "---------" + "\n");
}
} else {
scanResults.setText("Could not set up the detector!");
}
} catch (Exception e) {
Toast.makeText(this, "Failed to load Image", Toast.LENGTH_SHORT)
.show();
Log.e(LOG_TAG, e.toString());
}
}
}
private void takePicture() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
File photo = new File(Environment.getExternalStorageDirectory(), "picture.jpg");
imageUri = Uri.fromFile(photo);
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
startActivityForResult(intent, PHOTO_REQUEST);
}
@Override
protected void onSaveInstanceState(Bundle outState) {
if (imageUri != null) {
outState.putString(SAVED_INSTANCE_URI, imageUri.toString());
outState.putString(SAVED_INSTANCE_RESULT, scanResults.getText().toString());
}
super.onSaveInstanceState(outState);
}
private void launchMediaScanIntent() {
Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
mediaScanIntent.setData(imageUri);
this.sendBroadcast(mediaScanIntent);
}
private Bitmap decodeBitmapUri(Context ctx, Uri uri) throws FileNotFoundException {
int targetW = 600;
int targetH = 600;
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeStream(ctx.getContentResolver().openInputStream(uri), null, bmOptions);
int photoW = bmOptions.outWidth;
int photoH = bmOptions.outHeight;
int scaleFactor = Math.min(photoW / targetW, photoH / targetH);
bmOptions.inJustDecodeBounds = false;
bmOptions.inSampleSize = scaleFactor;
return BitmapFactory.decodeStream(ctx.getContentResolver()
.openInputStream(uri), null, bmOptions);
}
}