static BufferedImage twoColorImageWithAlpha(Color bg, Color fg, IBinaryImage image) {
  int fgInt = colorToInt(fg), bgInt = colorToInt(bg);
  ret image == null ?: bufferedImageFromFunctionWithAlpha(
    image.getWidth(), image.getHeight(), (x, y)
      -> image.getBoolPixel_noRangeCheck(x, y) ? fgInt : bgInt);
}

static BufferedImage twoColorImageWithAlpha(IBinaryImage image, Color bg, Color fg) {
  ret twoColorImageWithAlpha(bg, fg, image);
}