Java如何实现图像处理和P图？

<dependency>
	<groupId>net.coobird</groupId>
	<artifactId>thumbnailator</artifactId>
	<version>0.4.8</version>
</dependency>

/**
 * 横坐标
 */
private static final int x = 457;
/**
 * 纵坐标
 */
private static final int y = 295;
/**
 * 旋转角度
 */
private static final double angle = 16;
/**
 * 缩放比例
 */
private static final double scale = 0.18;
/**
 * 图片合成
 *
 * @param imagePath 待合成的图片路径
 * @param outPath 合成后的图片输出路径
 * @throws IOException
 */
private static void synthesis(String imagePath, String outPath) throws IOException {
	// 模板图
	BufferedImage template = ImageIO.read(new File("D:\local\images\template.png"));
	// 待合成图
	BufferedImage image = ImageIO.read(new File(imagePath));
	// 调整待合成图的尺寸和旋转角度
	image = Thumbnails.of(image).scale(scale).rotate(angle).asBufferedImage();
	// 合成后的图
	BufferedImage result = new BufferedImage(template.getWidth(), template.getHeight(), template.getType());
	Graphics2D graphics2D = result.createGraphics();
	// 先画待合成图，后画模板图，这样就能将待合成图放置在模板图的下层
	graphics2D.drawImage(image, x, y, null);
	graphics2D.drawImage(template,0,0, null);
	graphics2D.dispose();
	ImageIO.write(result, "png", new File(outPath));
}

public static void main(String[] args) throws IOException {
	synthesis("D:\local\images\weixin_payment_code.png", "D:\local\images\result.png");
}

/**
 * 调整亮度、对比度
 *
 * @param image
 */
private static void adjustBrightnessAndContrast(BufferedImage image) {
	int width = image.getWidth();
	int height = image.getHeight();
	for (int x = 0; x < width; x++) {
		for (int y = 0; y < height; y++) {
			Color color = new Color(image.getRGB(x, y));
			int red = calculateColor(color.getRed());
			int green = calculateColor(color.getGreen());
			int blue = calculateColor(color.getBlue());
			color = new Color(red, green, blue);
			image.setRGB(x, y, color.getRGB());
		}
	}
}
/**
 * 亮度，取值范围[-1,1]
 */
private static final double BRIGHTNESS = 0;
/**
 * 对比度，取值范围[-1,1]
 */
private static final double CONTRAST = -0.5;
/**
 * 计算亮度、对比度颜色值
 *
 * @param color 原颜色值
 * @return 返回计算后的颜色值
 */
private static int calculateColor(int color) {
	color = (int)((color - 127.5 * (1 - BRIGHTNESS)) * Math.tan((45 + 44 * CONTRAST) / 180 * Math.PI) + 127.5 * (1 + BRIGHTNESS));
	return getColor(color);
}
/**
 * 获取范围内的颜色值，[0,255]
 *
 * @param color
 * @return
 */
private static int getColor(int color) {
	return color > 255 ? 255 : color < 0 ? 0 : color;
}

...
// 调整待合成图的尺寸和旋转角度
image = Thumbnails.of(image).scale(scale).rotate(angle).asBufferedImage();
// 调整待合成图片的亮度、对比度
adjustBrightnessAndContrast(image);
...