title: face recognition log in to android application
body: <p>I am developing an android application for making messages private from the inbox   and user will login only by face recognition after which user can read the messages and send messages to private contacts. I am stuck here to use face recognition for user authentication.
  I have use Microsoft Subscription key and sample app and modify it for my application but I can not get the result only blank screen come. my activity class is this.</p>
  
  <pre><code>    public class Recognition extends AppCompatActivity {
      // Background task for face verification.
      private class VerificationTask extends AsyncTask&lt;Void, String, VerifyResult&gt; {
          // The IDs of two face to verify.
          private UUID mFaceId0;
          private UUID mFaceId1;
  
          VerificationTask (UUID faceId0, UUID faceId1) {
              mFaceId0 = faceId0;
              mFaceId1 = faceId1;
          }
  
          @Override
          protected VerifyResult doInBackground(Void... params) {
              // Get an instance of face service client to detect faces in image.
              FaceServiceClient faceServiceClient = SampleApp.getFaceServiceClient();
              try{
                  publishProgress("Verifying...");
  
                  // Start verification.
                  return faceServiceClient.verify(
                          mFaceId0,      /* The first face ID to verify */
                          mFaceId1);     /* The second face ID to verify */
              }  catch (Exception e) {
                  publishProgress(e.getMessage());
                  addLog(e.getMessage());
                  return null;
              }
          }
  
          @Override
          protected void onPreExecute() {
              progressDialog.show();
              addLog("Request: Verifying face " + mFaceId0 + " and face " + mFaceId1);
          }
  
          @Override
          protected void onProgressUpdate(String... progress) {
              progressDialog.setMessage(progress[0]);
              setInfo(progress[0]);
          }
  
          @Override
          protected void onPostExecute(VerifyResult result) {
              if (result != null) {
                  addLog("Response: Success. Face " + mFaceId0 + " and face "
                          + mFaceId1 + (result.isIdentical ? " " : " don't ")
                          + "belong to the same person");
              }
  
              // Show the result on screen when verification is done.
              setUiAfterVerification(result);
          }
      }
  
      // Background task of face detection.
      private class DetectionTask extends AsyncTask&lt;InputStream, String, Face[]&gt; {
          // Index indicates detecting in which of the two images.
          private int mIndex;
          private boolean mSucceed = true;
  
          DetectionTask(int index) {
              mIndex = index;
          }
  
          @Override
          protected Face[] doInBackground(InputStream... params) {
              // Get an instance of face service client to detect faces in image.
              FaceServiceClient faceServiceClient = SampleApp.getFaceServiceClient();
              try{
                  publishProgress("Detecting...");
  
                  // Start detection.
                  return faceServiceClient.detect(
                          params[0],  /* Input stream of image to detect */
                          true,       /* Whether to return face ID */
                          false,       /* Whether to return face landmarks */
                          /* Which face attributes to analyze, currently we support:
                             age,gender,headPose,smile,facialHair */
                          null);
              }  catch (Exception e) {
                  mSucceed = false;
                  publishProgress(e.getMessage());
                  addLog(e.getMessage());
                  return null;
              }
          }
  
          @Override
          protected void onPreExecute() {
              progressDialog.show();
              addLog("Request: Detecting in image" + mIndex);
          }
  
          @Override
          protected void onProgressUpdate(String... progress) {
              progressDialog.setMessage(progress[0]);
              setInfo(progress[0]);
          }
  
          @Override
          protected void onPostExecute(Face[] result) {
              // Show the result on screen when detection is done.
              setUiAfterDetection(result, mIndex, mSucceed);
          }
      }
  
      // Flag to indicate which task is to be performed.
      private static final int REQUEST_SELECT_IMAGE_0 = 0;
      private static final int REQUEST_SELECT_IMAGE_1 = 1;
      DataBaseHandler db = new DataBaseHandler(this);
  
      // The IDs of the two faces to be verified.
      private UUID mFaceId0;
      private UUID mFaceId1;
      List&lt;Contact&gt; contacts;
  
      // The two images from where we get the two faces to verify.
      private Bitmap mBitmap0;
      private Bitmap mBitmap1;
  
      // The adapter of the ListView which contains the detected faces from the two images.
      protected FaceListAdapter mFaceListAdapter0;
      protected FaceListAdapter mFaceListAdapter1;
  
      // Progress dialog popped up when communicating with server.
      ProgressDialog progressDialog;
  
      // When the activity is created, set all the member variables to initial state.
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_recognition);
  
  
  
          // Initialize the two ListViews which contain the thumbnails of the detected faces.
  
  
          progressDialog = new ProgressDialog(this);
          progressDialog.setTitle("Recognizing");
  
           take_photo();
          Intent intent=new Intent(Recognition.this,Inbox.class);
          startActivity(intent);
  
  
      }
      private Bitmap image_saved() {
          Bitmap theImage = null;
          contacts = db.getAllContacts();
          for (Contact cn : contacts) {
              String log = "ID:" + cn.getID() + " Name: " + cn.getName()
                      + " ,Image: " + cn.getImage();
              byte[] outImage = cn._image;
              ByteArrayInputStream imageStream = new     ByteArrayInputStream(outImage);
              theImage = BitmapFactory.decodeStream(imageStream);
      //            imageView.setImageBitmap(theImage);
      //            username.setText(cn.getName());
          detect(theImage,1);
          }
          if (theImage != null) {
  
          }
          return theImage;
  
      }
  
  
      public void take_photo() {
          Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
          intent.putExtra("android.intent.extras.CAMERA_FACING", android.hardware.Camera.CameraInfo.CAMERA_FACING_FRONT);
          intent.putExtra("android.intent.extras.LENS_FACING_FRONT", 1);
          intent.putExtra("android.intent.extra.USE_FRONT_CAMERA", true);
          startActivityForResult(intent, REQUEST_SELECT_IMAGE_0);
      }
  
      // Called when image selection is done. Begin detecting if the image is selected successfully.
      @Override
      protected void onActivityResult(int requestCode, int resultCode, Intent data) {
          // Index indicates which of the two images is selected.
  
  
          if(resultCode == REQUEST_SELECT_IMAGE_0) {
              // If image is selected successfully, set the image URI and bitmap.
              Bitmap bitmap = ImageHelper.loadSizeLimitedBitmapFromUri(
                      data.getData(), getContentResolver());
              if (bitmap != null) {
                  // Image is select but not detected, disable verification button.
             int index=0;
  
                  // Set the image to detect.
                  if (index == 0) {
                      mBitmap0 = bitmap;
                      mFaceId0 = null;
                  } else
                  {
                      mBitmap1 = bitmap;
                      mFaceId1 = null;
                  }
  
                  // Add verification log.
                  addLog("Image" + index + ": " + data.getData() + " resized to " + bitmap.getWidth()
                          + "x" + bitmap.getHeight());
                  detect(  image_saved(),1);
                  // Start detecting in image.
                  detect(bitmap, index);
                 next();
                  Toast.makeText(Recognition.this,"Image Not Match",Toast.LENGTH_SHORT).show();
  
  
              }
          }
      }
  
      private boolean next() {
  
          new VerificationTask(mFaceId0, mFaceId1).execute();
          return true;
      }
  
      private void setUiAfterVerification(VerifyResult result) {
          // Verification is done, hide the progress dialog.
          progressDialog.dismiss();
  
          // Enable all the buttons.
  
  
          // Show verification result.
          if (result != null) {
              DecimalFormat formatter = new DecimalFormat("#0.00");
              String verificationResult = (result.isIdentical ? "The same person": "Different persons")
                      + ". The confidence is " + formatter.format(result.confidence);
              setInfo(verificationResult);
          }
      }
  
      // Show the result on screen when detection in image that indicated by index is done.
      private void setUiAfterDetection(Face[] result, int index, boolean succeed) {
  
  
          if (succeed) {
              addLog("Response: Success. Detected "
                      + result.length + " face(s) in image" + index);
  
              setInfo(result.length + " face" + (result.length != 1 ? "s": "")  + " detected");
  
              // Show the detailed list of detected faces.
  
              // Set the default face ID to the ID of first face, if one or more faces are detected.
  
          }
  
          if (result != null &amp;&amp; result.length == 0) {
              setInfo("No face detected!");
          }
  
          if ((index == 0 &amp;&amp; mBitmap1 == null) || (index == 1 &amp;&amp; mBitmap0 == null) || index == 2) {
              progressDialog.dismiss();
          }
  
          if (mFaceId0 != null &amp;&amp; mFaceId1 != null) {
           }
      }
  
      // Start detecting in image specified by index.
      private void detect(Bitmap bitmap, int index) {
          // Put the image into an input stream for detection.
          ByteArrayOutputStream output = new ByteArrayOutputStream();
          bitmap.compress(Bitmap.CompressFormat.JPEG, 100, output);
          ByteArrayInputStream inputStream = new ByteArrayInputStream(output.toByteArray());
  
          // Start a background task to detect faces in the image.
          new DetectionTask(index).execute(inputStream);
  
  
          // Set the status to show that detection starts.
          setInfo("Detecting...");
      }
  
      // Set the information panel on screen.
      private void setInfo(String info) {
          TextView textView = (TextView) findViewById(R.id.info);
          textView.setText(info);
      }
  
      // Add a log item.
      private void addLog(String log) {
          LogHelper.addVerificationLog(log);
      }
  
      // The adapter of the GridView which contains the thumbnails of the detected faces.
      private abstract class FaceListAdapter extends BaseAdapter {
          // The detected faces.
          List&lt;Face&gt; faces;
  
          int mIndex;
  
          // The thumbnails of detected faces.
          List&lt;Bitmap&gt; faceThumbnails;
  
          // Initialize with detection result and index indicating on which image the result is got.
          FaceListAdapter(Face[] detectionResult, int index) {
              faces = new ArrayList&lt;&gt;();
              faceThumbnails = new ArrayList&lt;&gt;();
              mIndex = index;
  
              if (detectionResult != null) {
                  faces = Arrays.asList(detectionResult);
                  for (Face face : faces) {
                      try {
                          // Crop face thumbnail without landmarks drawn.
                          faceThumbnails.add(ImageHelper.generateFaceThumbnail(
                                  index == 0 ? mBitmap0 : mBitmap1, face.faceRectangle));
                      } catch (IOException e) {
                          // Show the exception when generating face thumbnail fails.
                          setInfo(e.getMessage());
                      }
                  }
              }
          }
  
          @Override
          public int getCount() {
              return faces.size();
          }
  
          @Override
          public Object getItem(int position) {
              return faces.get(position);
          }
  
          @Override
          public long getItemId(int position) {
              return position;
          }
  
      } 
  }
  </code></pre>