public synchronized void startPreview() {
    Camera theCamera = camera;
    if (theCamera != null && !previewing) {
      theCamera.startPreview();
      previewing = true;
      autoFocusManager = new AutoFocusManager(context, camera);
    }
  }
Asks the camera hardware to begin drawing preview frames to the screen.
OCRTest/src/main/java/edu/sfsu/cs/orange/ocr/camera/CameraManager.java