private void restartOcrPreview() {    
    // Display the shutter and torch buttons
    activity.setButtonVisibility(true);

    if (state == State.SUCCESS) {
      state = State.PREVIEW;
      
      // Draw the viewfinder.
      activity.drawViewfinder();
    }
  }
Start the preview, but don't try to OCR anything until the user presses the shutter button.
OCRTest/src/main/java/edu/sfsu/cs/orange/ocr/CaptureActivityHandler.java