java在图片上加盖公章和添加水印

在Java中添加水印和公章可以使用Java的图像处理库 - ImageIO和Graphics2D。下面是一个简单的示例代码，演示如何在一张图片上添加水印和公章：

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;

public class AddWatermark {
    public static void main(String[] args) throws Exception {
        String imagePath = "test.jpg";
        String watermarkPath = "watermark.png";
        String sealPath = "seal.png";
        BufferedImage image = ImageIO.read(new File(imagePath));
        BufferedImage watermark = ImageIO.read(new File(watermarkPath));
        BufferedImage seal = ImageIO.read(new File(sealPath));
        
        Graphics2D g = image.createGraphics();
        int watermarkWidth = image.getWidth() / 3;
        int watermarkHeight = watermarkWidth * watermark.getHeight() / watermark.getWidth();
        g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, 0.5f));
        g.drawImage(watermark, image.getWidth() - watermarkWidth, image.getHeight() - watermarkHeight, watermarkWidth, watermarkHeight, null);
        
        int sealWidth = image.getWidth() / 4;
        int sealHeight = sealWidth * seal.getHeight() / seal.getWidth();
        g.drawImage(seal, image.getWidth() / 2 - sealWidth / 2, image.getHeight() / 2 - sealHeight / 2, sealWidth, sealHeight, null);
        g.dispose();
        
        ImageIO.write(image, "jpg", new File("result.jpg"));
    }
}

这个示例代码加载了一张名为test.jpg的图片，以及两张水印和公章图片。它使用Graphics2D把水印和公章添加到原始图片上，并将结果保存到result.jpg文件中。

您也可以根据需要调整代码。希望这可以帮到您！