static L<Int> imagePixelsToRGBAWithSize_virtualIntList(BufferedImage etc img) {
  if (img == null) null;
  int w = img.getWidth(), h = img.getHeight(), n = w*h+2;

  ret new RandomAccessAbstractList<Int>() {
    public int size() { ret n; }
    
    public Int get(int i) {
      if (i == 0) ret w;
      if (i == 1) ret h;
      i -= 2;
      ret img.getRGB(i % w, i / w);
    }
    
    public Int set(int i, Int val) {
      if (i < 2) fail();
      i -= 2;
      int old = img.getRGB(i % w, i / w);
      if (old != (int) val)
        img.setRGB(i % w, i / w, val);
      ret old;
    }
  };
}