@Override
	public void doChangeBrightness(int brightnessAmountNum) {
		if (imageManager.getBufferedImage() == null)
			return;
		WritableRaster raster = imageManager.getBufferedImage().getRaster();
		for (int x = 0; x < raster.getWidth(); x++) {
			for (int y = 0; y < raster.getHeight(); y++) {
				double[] pixel = new double[3];
				raster.getPixel(x, y, pixel);
				if (pixel[0] + brightnessAmountNum > 255)
					pixel[0] = 255;
				else if (pixel[0] + brightnessAmountNum < -255)
					pixel[0] = -255;
				else
					pixel[0] += brightnessAmountNum;
				pixel[1] = pixel[0]; pixel[2] = pixel[0];
				raster.setPixel(x, y, pixel);
			}
		}
		GUIFunctions.refresh();
	}