// Public function to be called in order to trigger OCR
 public void DoOCR()
 {
     Globals.instance.textToSpeech.StartSpeaking("Reading text.");
     callbackFunction = ExecuteOCR;
     StartPhotoCapture();
 }
 // Public function to be called in order to trigger FaceRecognition
 public void DoFaceRecognition()
 {
     Globals.instance.textToSpeech.StartSpeaking("Searching for Faces.");
     callbackFunction = ExecuteFaceTracking;
     StartPhotoCapture();
 }