title: No implementation found for long org.opencv.core.Mat.n_Mat(int, int, int)
body: <p>I am trying to get the width and height of the image, ImageView variable is <strong>iv</strong>. But it seems like I always get below error.</p>
  
  <pre><code>java.lang.UnsatisfiedLinkError: No implementation found for long org.opencv.core.Mat.n_Mat(int, int, int) (tried Java_org_opencv_core_Mat_n_1Mat and Java_org_opencv_core_Mat_n_1Mat__III)
  at org.opencv.core.Mat.n_Mat(Native Method)
  at org.opencv.core.Mat.&lt;init&gt;(Mat.java:37)
  at com.example.backup.contour_image.MainActivity.onTouch(MainActivity.java:56)
  </code></pre>
  
  <p><strong>My Code</strong></p>
  
  <pre><code>public boolean onTouch(View v, MotionEvent event)
  {
      Bitmap bm =((BitmapDrawable)iv.getDrawable()).getBitmap();
  
      int w = iv.getWidth();
      int h = iv.getHeight();
  
      mRgba = new Mat(w,h,CvType.CV_8UC4); &lt;---- the error of line being described
  
      int cols = mRgba.cols();
      int rows = mRgba.rows();
  
      int x = (int)event.getX();
      int y = (int)event.getY();
  }
  </code></pre>