public void mirrorHorizontally() {
		byte[] newData = new byte[width*height];
		
		for (int j=0; j<height; j++) {
			for (int i=0; i<width; i++) {
				newData[j*width + i] = data[j*width + width-i-1];
			}
		}
		
		data = newData;
	}