JAVA实现图片叠加效果

 1 import java.awt.AlphaComposite;
 2 import java.awt.Graphics2D;
 3 import java.awt.image.BufferedImage;
 4 import java.io.File;
 5 import java.io.IOException;
 6
 7 import javax.imageio.ImageIO;
 8 public class NewImageUtils {
 9     /**
10      *
11      * @Title: 构造图片
12      * @Description: 生成水印并返回java.awt.image.BufferedImage
13      * @param file
14      *            源文件(图片)
15      * @param waterFile
16      *            水印文件(图片)
17      * @param x
18      *            距离右下角的X偏移量
19      * @param y
20      *            距离右下角的Y偏移量
21      * @param alpha
22      *            透明度, 选择值从0.0~1.0: 完全透明~完全不透明
23      * @return BufferedImage
24      * @throws IOException
25      */
26     public static BufferedImage watermark(File file, File waterFile, int x, int y, float alpha) throws IOException {
27         // 获取底图
28         BufferedImage buffImg = ImageIO.read(file);
29         // 获取层图
30         BufferedImage waterImg = ImageIO.read(waterFile);
31         // 创建Graphics2D对象，用在底图对象上绘图
32         Graphics2D g2d = buffImg.createGraphics();
33         int waterImgWidth = waterImg.getWidth();// 获取层图的宽度
34         int waterImgHeight = waterImg.getHeight();// 获取层图的高度
35         // 在图形和图像中实现混合和透明效果
36         g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));
37         // 绘制
38         g2d.drawImage(waterImg, x, y, waterImgWidth, waterImgHeight, null);
39         g2d.dispose();// 释放图形上下文使用的系统资源
40         return buffImg;
41     }
42
43     /**
44      * 输出水印图片
45      *
46      * @param buffImg
47      *            图像加水印之后的BufferedImage对象
48      * @param savePath
49      *            图像加水印之后的保存路径
50      */
51     private void generateWaterFile(BufferedImage buffImg, String savePath) {
52         int temp = savePath.lastIndexOf(".") + 1;
53         try {
54             ImageIO.write(buffImg, savePath.substring(temp), new File(savePath));
55         } catch (IOException e1) {
56             e1.printStackTrace();
57         }
58     }
59
60     /**
61      *
62      * @param args
63      * @throws IOException
64      *             IO异常直接抛出了
65      * @author bls
66      */
67     public static void main(String[] args) throws IOException {
68         String sourceFilePath = "D://img//di.png";
69         String waterFilePath = "D://img//ceng.png";
70         String saveFilePath = "D://img//new.png";
71         NewImageUtils newImageUtils = new NewImageUtils();
72         // 构建叠加层
73         BufferedImage buffImg = NewImageUtils.watermark(new File(sourceFilePath), new File(waterFilePath), 0, 0, 1.0f);
74         // 输出水印图片
75         newImageUtils.generateWaterFile(buffImg, saveFilePath);
76     }
77 }