java-为指定的图像文件加透明阴影

待我称王封你为后i 2021-06-24 15:57 437阅读 0赞

import java.awt.AlphaComposite;
    import java.awt.Color;
    import java.awt.Graphics2D;
    import java.awt.Transparency;
    import java.awt.image.BufferedImage;
    import java.io.File;
    import javax.imageio.ImageIO;
    
    public class AddShadow {
    	/**
    	 * @param srcFile
    	 *            源图像文件
    	 * @param x
    	 *            阴影宽度
    	 * @param y
    	 *            阴影高度
    	 * @param color
    	 *            阴影颜色
    	 * @param alpha
    	 *            透明度，0－1之间取值
    	 * @throws Exception
    	 *             为指定的文件加上透明阴影
    	 */
    	public final static void add(File srcFile, int x, int y, Color color,
    			float alpha) throws Exception {
    		// 读取源文件
    		BufferedImage srcImg = ImageIO.read(srcFile);
    		// 在新建一个图像缓冲区，大小包括阴影部分
    		BufferedImage bufImg = new BufferedImage(srcImg.getWidth() + x,
    				srcImg.getHeight() + y, BufferedImage.TYPE_INT_RGB);
    		Graphics2D g = bufImg.createGraphics();
    		// 创建一个支持有透明度的图像缓冲区
    		bufImg = g.getDeviceConfiguration().createCompatibleImage(
    				srcImg.getWidth() + x, srcImg.getHeight() + y,
    				Transparency.TRANSLUCENT);
    		g.dispose();
    		// 画阴影部分
    		g = bufImg.createGraphics();
    		g.setComposite(AlphaComposite.getInstance(AlphaComposite.XOR, alpha));
    		g.setColor(Color.black);
    		g.setBackground(Color.red);
    		g.fillRect(x, y, srcImg.getWidth(), srcImg.getHeight());
    		g.dispose();
    		// 画源图像
    		g = bufImg.createGraphics();
    		g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC, 1));
    		g.drawImage(srcImg, 0, 0, null);
    		g.dispose();
    		String oldName = srcFile.getName();
    		// 目标文件必须是PNG文件
    		String fileName = "d:/ccc/"
    				+ oldName.substring(0, oldName.length() - 4) + ".png";
    		ImageIO.write(bufImg, "PNG", new File(fileName));
    	}
    
    	public static void main(String[] args) throws Exception {
    		// TODO Auto-generated method stub
    		File f = new File("d:/ccc");
    		File imgFiles[] = f.listFiles(new ImageFilter());
    		for (File x : imgFiles) {
    			System.out.println(x.getName() + "正在加阴影...");
    			add(x, 20, 20, Color.red, 0.3f);
    		}
    		System.out.println("阴影添加成功，阴影文件扩展名为.png");
    	}
    }