javaftp照片加水印 图片加水印 java

1.水印图片（正水印）截图：

2、斜水印

3.具体实现代码如下：

package test;
 import java.awt.AlphaComposite;
 import java.awt.Color;
 import java.awt.Font;
 import java.awt.Graphics2D;
 import java.awt.Image;
 import java.awt.RenderingHints;
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.InputStream;
 import java.io.OutputStream;
 import javax.imageio.ImageIO;
  
 /**
  * 
  * @author zxs
  * @date 2019年8月14日 
  */
 public class SYTest {
     // 水印透明度
     private static float alpha = 0.3f;
     // 水印文字大小
     public static final int FONT_SIZE = 25;
     // 水印文字字体
     private static Font font = new Font ("微软雅黑", Font.BOLD, FONT_SIZE);
     // 水印文字颜色
     private static Color color = Color.white;
     // 水印之间的间隔
     private static final int XMOVE = 70;
     // 水印之间的间隔
     private static final int YMOVE = 70;
  
     /**
      * 获取文本长度。汉字为1:1，英文和数字为2:1
      */
     private static int getTextLength (String text) {
         int length = text.length ();
         for (int i = 0; i < text.length (); i++) {
             String s = String.valueOf (text.charAt (i));
             if (s.getBytes ().length > 1) {
                 length++;
             }
         }
         length = length % 2 == 0 ? length / 2 : length / 2 + 1;
         return length;
     }
  
     /**
      * 给图片添加水印文字
      * 
      * @param logoText 水印文字
      * @param srcImgPath 源图片路径
      * @param targerPath 目标图片路径
      */
     public static void ImageByText (String logoText, String srcImgPath, String targerPath) {
         ImageByText (logoText, srcImgPath, targerPath, null);
     }
  
     /**
      * 给图片添加水印文字、可设置水印文字的旋转角度
      * 
      * @param logoText
      * @param srcImgPath
      * @param targerPath
      * @param degree
      */
     public static void ImageByText (String logoText, String srcImgPath, String targerPath, Integer degree) {
  
         InputStream is = null;
         OutputStream os = null;
         try {
             // 源图片
             Image srcImg = ImageIO.read (new File (srcImgPath));
             int width = srcImg.getWidth (null);// 原图宽度
             int height = srcImg.getHeight (null);// 原图高度
             BufferedImage buffImg = new BufferedImage (srcImg.getWidth (null), srcImg.getHeight (null),
                                                        BufferedImage.TYPE_INT_RGB);
             // 得到画笔对象
             Graphics2D g = buffImg.createGraphics ();
             // 设置对线段的锯齿状边缘处理
             g.setRenderingHint (RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
             g.drawImage (srcImg.getScaledInstance (srcImg.getWidth (null), srcImg.getHeight (null), Image.SCALE_SMOOTH),
                          0, 0, null);
             // 设置水印旋转
             if (null != degree) {
                 g.rotate (Math.toRadians (degree), (double) buffImg.getWidth () / 2, (double) buffImg.getHeight () / 2);
             }
             // 设置水印文字颜色
             g.setColor (color);
             // 设置水印文字Font
             g.setFont (font);
             // 设置水印文字透明度
             g.setComposite (AlphaComposite.getInstance (AlphaComposite.SRC_ATOP, alpha));
  
             int x = -width / 2;
             int y = -height / 2;
             int markWidth = FONT_SIZE * getTextLength (logoText);// 字体长度
             int markHeight = FONT_SIZE;// 字体高度
  
             // 循环添加水印
             while (x < width * 1.5) {
                 y = -height / 2;
                 while (y < height * 1.5) {
                     g.drawString (logoText, x, y);
  
                     y += markHeight + YMOVE;
                 }
                 x += markWidth + XMOVE;
             }
             // 释放资源
             g.dispose ();
             // 生成图片
             os = new FileOutputStream (targerPath);
             ImageIO.write (buffImg, "JPG", os);
             System.out.println ("添加水印文字成功!");
         } catch (Exception e) {
             e.printStackTrace ();
         } finally {
             try {
                 if (null != is)
                     is.close ();
             } catch (Exception e) {
                 e.printStackTrace ();
             }
             try {
                 if (null != os)
                     os.close ();
             } catch (Exception e) {
                 e.printStackTrace ();
             }
         }
     }
     
     public static void main(String[] args) {
         //最后一个参数为null时，添加的水印是正着的，如果要添加斜水印，传值为-45即可
         ImageByText("卡哇伊", "E:/image/2.png", "E:/image/SY2.jpg", -45);
     }
 }