В Android вы можете сделать это следующим образом:
@Override
protected Result doInBackground(Void... params)
{
try
{
InputStream inputStream = activity.getContentResolver().openInputStream(uri);
Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
if (bitmap == null)
{
Log.e(TAG, "uri is not a bitmap," + uri.toString());
return null;
}
int width = bitmap.getWidth(), height = bitmap.getHeight();
int[] pixels = new int[width * height];
bitmap.getPixels(pixels, 0, width, 0, 0, width, height);
bitmap.recycle();
bitmap = null;
RGBLuminanceSource source = new RGBLuminanceSource(width, height, pixels);
BinaryBitmap bBitmap = new BinaryBitmap(new HybridBinarizer(source));
MultiFormatReader reader = new MultiFormatReader();
try
{
Result result = reader.decode(bBitmap);
return result;
}
catch (NotFoundException e)
{
Log.e(TAG, "decode exception", e);
return null;
}
}
catch (FileNotFoundException e)
{
Log.e(TAG, "can not open file" + uri.toString(), e);
return null;
}
}