private static int[] findFirstDiff(BufferedImage image1, PixImage image2,
			int border) {
		if (image1.getWidth() != image2.getWidth()
				|| image1.getHeight() != image2.getHeight()) {
			return new int[] { -1, -1 };
		}
		BufferedImage bImage2 = ImageUtils.pixImage2buffer(image2);
		for (int y = border; y < image1.getHeight() - border; y++) {
			for (int x = border; x < image1.getWidth() - border; x++) {
				if (image1.getRGB(x, y) != bImage2.getRGB(x, y)) {
					return new int[] { x, y };
				}
			}
		}
		return null;
	}