srecord RenderRecognizedBox(IRecognizedBox box) is Renderable {
  settable Color outerColor = Color.red;
  settable Color innerColor = Color.green;
  
  public void renderOn(Graphics2D g, int w, int h) {
    Rect r = box.bounds();
    r = growRect(r);
    drawRect(g, innerColor, r);
    r = growRect(r);
    drawRect(g, outerColor, r);
  }
}