static BufferedImage scaleBufferedImageToMaxWidthOrHeight(int max, BufferedImage img) {
  int w = img.getWidth(), h = img.getHeight();
  if (w <= max && h <= max) ret img;
  double scale = max/(double) max(w, h);
  ret scaleImage(img, scale);
}

static BufferedImage scaleBufferedImageToMaxWidthOrHeight(BufferedImage img, int max) {
  ret scaleBufferedImageToMaxWidthOrHeight(max, img);
}