Java实现图片加水印且控制位置和透明度.docVIP

Java实现图片加水印且控制位置和透明度 昨天要做一个给图片加水印的功能，不想使用一些插件，就在网上转了一会儿，经过改装成了我需要的功能，代码如下： package org.guhao; import java.awt.AlphaComposite;import java.awt.Graphics2D;import java.awt.Image;import java.awt.image.BufferedImage;import java.io.File;import java.text.SimpleDateFormat;import java.util.Date; import javax.imageio.ImageIO; public class TestWatermark { /*** 图片水印* @param pressimg 水印图片* @param targetimg 目标图片* @param location 位置：1、左上角，2、右上角，3、左下角，4、右下角，5、正中间* @param alpha 透明度*/public static void pressImage(String pressimg, String targetimg, int location, float alpha) {try {//读取目标图片File img = new File(targetimg);Image src = ImageIO.read(img);int width = src.getWidth(null);int height = src.getHeight(null);BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);Graphics2D g = image.createGraphics();g.drawImage(src, 0, 0, width, height, null);//水印文件Image src_biao = ImageIO.read(new File(pressimg));int width_biao = src_biao.getWidth(null);int height_biao = src_biao.getHeight(null); //如果水印图片高或者宽大于目标图片是做的处理,使其水印宽或高等于目标图片的宽高，并且等比例缩放int new_width_biao = width_biao;int new_height_biao = height_biao;if(width_biao width){new_width_biao = width;new_height_biao = (int) ((double)new_width_biao/width_biao*height);}if(new_height_biao height){new_height_biao = height;new_width_biao = (int) ((double)new_height_biao/height_biao*new_width_biao);} //根据位置参数确定坐标位置int x = 0;int y = 0;switch(location){case 1:break;case 2:x = width – new_width_biao;break;case 3:y = height – new_height_biao;break;case 4:x = width – new_width_biao;y = height – new_height_biao;break;case 5:x = (width – new_width_biao)/2;y = (height – new_height_biao)/2;break;default:break;} g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));g.drawImage(src_biao, x, y, new_width_biao, new_height_biao, null);//水印文件结束g.dispose();ImageIO.write( image, “png”, img);} catch (Exception e) {e.printStackTrace();}}} 这个功能我用1000张图片做测试