java处理图片 添加文字或图片水印并可生成缩略图

ImageHelper.java

package com.test1433;

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.geom.AffineTransform;
    import java.awt.image.BufferedImage;
    import java.awt.image.ColorModel;
    import java.awt.image.WritableRaster;
    import java.io.File;
    import java.io.FileOutputStream;
    import javax.imageio.ImageIO;
    import com.sun.image.codec.jpeg.JPEGCodec;
    import com.sun.image.codec.jpeg.JPEGImageEncoder;
     
    public class ImageHelper {
     
/**
 * 生成缩略图 <br/>保存:ImageIO.write(BufferedImage, imgType[jpg/png/...], File);
 *
 * @param source
 *            原图片
 * @param width
 *            缩略图宽
 * @param height
 *            缩略图高
 * @param b
 *            是否等比缩放
 * */
public static BufferedImage Thumb(BufferedImage source, int width,
        int height, boolean b) {
// targetW，targetH分别表示目标长和宽
                int type = source.getType();
                BufferedImage target = null;
                double sx = (double) width / source.getWidth();
                double sy = (double) height / source.getHeight();
 
                if (b) {
                        if (sx > sy) {
                                sx = sy;
                                width = (int) (sx * source.getWidth());
                        } else {
                                sy = sx;
                                height = (int) (sy * source.getHeight());
                        }
                }
                 
                if (type == BufferedImage.TYPE_CUSTOM) { // handmade
        ColorModel cm = source.getColorModel();
        WritableRaster raster = cm.createCompatibleWritableRaster(width,
                        height);
        boolean alphaPremultiplied = cm.isAlphaPremultiplied();
        target = new BufferedImage(cm, raster, alphaPremultiplied, null);
                } else
        target = new BufferedImage(width, height, type);
                Graphics2D g = target.createGraphics();
// smoother than exlax:
        g.setRenderingHint(RenderingHints.KEY_RENDERING,
                        RenderingHints.VALUE_RENDER_QUALITY);
        g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy));
        g.dispose();
        return target;
        }
 
        /**
 * 图片水印
 *
 * @param imgPath
 *            待处理图片
 * @param markPath
 *            水印图片
 * @param x
 *            水印位于图片左上角的 x 坐标值
 * @param y
 *            水印位于图片左上角的 y 坐标值
 * @param alpha
 *            水印透明度 0.1f ~ 1.0f
 * */
public static void waterMark(String imgPath, String markPath, int x, int y,
                float alpha) {
        try {
        // 加载待处理图片文件
             Image img = ImageIO.read(new File(imgPath));
 
             BufferedImage image = new BufferedImage(img.getWidth(null), img
                                        .getHeight(null), BufferedImage.TYPE_INT_RGB);
             Graphics2D g = image.createGraphics();
             g.drawImage(img, 0, 0, null);
 
             // 加载水印图片文件
             Image src_biao = ImageIO.read(new File(markPath));
             g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
                     alpha));
             g.drawImage(src_biao, x, y, null);
                        g.dispose();
         // 保存处理后的文件
        FileOutputStream out = new FileOutputStream(imgPath);
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
        encoder.encode(image);
        out.close();
        } catch (Exception e) {
                e.printStackTrace();
        }
}
 
        /**
 * 文字水印
 *
 * @param imgPath
 *            待处理图片
 * @param text
 *            水印文字
 * @param font
 *            水印字体信息
 * @param color
 *            水印字体颜色
 * @param x
 *            水印位于图片左上角的 x 坐标值
 * @param y
 *            水印位于图片左上角的 y 坐标值
 * @param alpha
 *            水印透明度 0.1f ~ 1.0f
 */
 
public static void textMark(String imgPath, String text, Font font,
                Color color, int x, int y, float alpha) {
        try {
            Font Dfont = (font == null) ? new Font("宋体", 20, 13) : font;
         
            Image img = ImageIO.read(new File(imgPath));
         
            BufferedImage image = new BufferedImage(img.getWidth(null), img
                                                .getHeight(null), BufferedImage.TYPE_INT_RGB);
            Graphics2D g = image.createGraphics();
         
           g.drawImage(img, 0, 0, null);
           g.setColor(color);
           g.setFont(Dfont);
           g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
                                                alpha));
           g.drawString(text, x, y);
           g.dispose();
           FileOutputStream out = new FileOutputStream(imgPath);
           JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
           encoder.encode(image);
           out.close();
          } catch (Exception e) {
                System.out.println(e);
          }
        }
    }

测试代码

package com.test1433;

import java.awt.Color;
import java.awt.Font;

public class TestPic {
    
    public static void main(String[] args) {
        Font font = new Font("宋体",50,60);
        Color color = new Color(0,0,0);
        ImageHelper.textMark("c://2012.jpg","http://www.baidu.com",font,color,20,40,1f);
    }
 
}