title: SURF Feature Extraction With Android OpenCV SDK - Getting Some Errors
body: <p>I am trying to implement SURF features in my project which is about face recognition. I am new at opencv on android. So it is a little bit hard to find logical errors. Also i tried to search from google but nothing i could fix.
  I imported the libray org.opencv.features2d for handling feature issues.</p>
  
  <p>At the beginning this is my SURF implementation code(a part of).</p>
  
  <pre><code>    public void SURFExtraction()
  {
      FeatureDetector detector = FeatureDetector.create(FeatureDetector.SURF);
      DescriptorExtractor SurfExtractor = DescriptorExtractor.create(DescriptorExtractor.SURF);
  
       Mat img1 = Highgui.imread("/mnt/sdcard/FaceDB/1.jpg");//one of my face
       Mat img2 = Highgui.imread("/mnt/sdcard/FaceDB/2.jpg");//one of my different face
  
      //extract keypoints
      MatOfKeyPoint keypoints = new MatOfKeyPoint();
      MatOfKeyPoint logoKeypoints = new MatOfKeyPoint();
  
       detector.detect(img1, keypoints);//this is the problem "fatal signal"
       Log.d("LOG!", "number of query Keypoints= " + keypoints.size());
       detector.detect(img2, logoKeypoints);
       Log.d("LOG!", "number of logo Keypoints= " + logoKeypoints.size());
  
  
  }
  </code></pre>
  
  <p>When i execute the program it gives a single error. Just this.</p>
  
  <pre><code>  A/libc(30444): Fatal signal 11 (SIGSEGV) at 0x00000000 (code=1)
  </code></pre>
  
  <p>I searched for this error. They said that this error occurs when native classes try to reach or write 0x00000000 memory address. But i couldn't figure out how to fix this issue.
  Can you tell me what can i do? </p>
  
  <p>Thanks in advance</p>