OpenCV in Android

Question

I am using Opencv in android and I want to load an image from gallery to Mat , please check my code and help in what I did wrong?

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

    if (requestCode == GALLERY_INTENT && resultCode == RESULT_OK) {

        Uri imageUri = data.getData();
        String selectedImagePath = getPath(imageUri);

    Mat imgRgba = Imgcodecs.imread( selectedImagePath );
    Mat img = new Mat();
    imgRgba.copyTo(img);
   }

private String getPath(Uri imageUri) {
    String[] projection = {MediaStore.Images.Media.DATA};
    Cursor cursor = getContentResolver().query( imageUri, projection, null, null, null );
    if(cursor!=null){
        int column_index = cursor.getColumnIndexOrThrow( MediaStore.Images.Media.DATA );
        cursor.moveToFirst();
        return cursor.getString( column_index );

    }

    return imageUri.getPath();
}

When I run it it crashes with : java.lang.UnsatisfiedLinkError: No implementation found for long org.opencv.imgcodecs.Imgcodecs.imread_1(java.lang.String) (tried Java_org_opencv_imgcodecs_Imgcodecs_imread_11 and Java_org_opencv_imgcodecs_Imgcodecs_imread_11__Ljava_lang_String_2) at org.opencv.imgcodecs.Imgcodecs.imread_1(Native Method) at org.opencv.imgcodecs.Imgcodecs.imread(Imgcodecs.java:118)

Answer 1

You hava to initialize OpenCV library before using on Android.

Call below code before use OpenCV

OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_11, this, baseLoaderCallback);

And then, below method will be callback.

  @Override
  public void onManagerConnected(int status) {
       switch (status) {
            case LoaderCallbackInterface.SUCCESS:
            {
                 Log.i(TAG, "OpenCV loaded successfully");
            } break;
            default:
            {
                 super.onManagerConnected(status);
            } break;
       }
  }

};