ImageUtils.java：图片处理工具类[裁剪/图片水印/文字水印/缩放补白/Base64加密解密]
图片处理工具类\[裁剪/图片水印/文字水印/缩放补白/Base64加密解密\]
JavaWeb工具类目录 [http://baike.xsoftlab.net/view/1059.html](http://baike.xsoftlab.net/view/1059.html)
用到的jar包：
[commons-beanutils-1.8.0.jar](http://central.maven.org/maven2/commons-beanutils/commons-beanutils/1.8.0/commons-beanutils-1.8.0.jar)
[commons-codec-1.10.jar](http://central.maven.org/maven2/commons-codec/commons-codec/1.10/commons-codec-1.10.jar)
源码：
```java
package com.zhenzhigu.commons.util;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Iterator;
import javax.imageio.ImageIO;
import javax.imageio.ImageReadParam;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
/**
* 图片工具类:
* 功能：[裁剪/图片水印/文字水印/缩放补白/Base64加密解密]
* @author Master.Xia date:2016年11月17日11:52:38
*/
public final class ImageUtils {
/**图片格式：JPG*/
private static final String PICTRUE_FORMATE_JPG = "jpg";
private ImageUtils(){}
/**
* 图片裁剪
* @param src 原始图片输入流
* @param out 成品图片输出流
* @param x 开始位置的x坐标
* @param y 开始位置的y坐标
* @param width 裁剪的宽度
* @param height 裁剪的高度
* @throws IOException
*/
public static void cut(InputStream src, OutputStream out, int x, int y,int width, int height) throws IOException {
Iterator<ImageReader> iterator = ImageIO.getImageReadersByFormatName("jpg");
ImageReader reader = (ImageReader) iterator.next();
ImageInputStream iis = ImageIO.createImageInputStream(src);
reader.setInput(iis, true);
ImageReadParam param = reader.getDefaultReadParam();
Rectangle rect = new Rectangle(x, y, width, height);
param.setSourceRegion(rect);
BufferedImage bi = reader.read(0, param);
ImageIO.write(bi, "jpg", out);
}
/**
* 添加图片水印
* @param src 原始图片输入流
* @param out 成品图片输出流
* @param water 水印图片输入流
* @param x 水印图片距离目标图片左侧的偏移量，如果x<0, 则在正中间
* @param y 水印图片距离目标图片上侧的偏移量，如果y<0, 则在正中间
* @param alpha 水印透明度(0.0 -- 1.0, 0.0为完全透明，1.0为完全不透明)
*/
public final static void watermark(InputStream src,OutputStream out, InputStream water, int x, int y, float alpha) {
try {
Image image = ImageIO.read(src);
int width = image.getWidth(null);
int height = image.getHeight(null);
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bufferedImage.createGraphics();
g.drawImage(image, 0, 0, width, height, null);
Image waterImage = ImageIO.read(water); // 水印文件
int width_1 = waterImage.getWidth(null);
int height_1 = waterImage.getHeight(null);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));
int widthDiff = width - width_1;
int heightDiff = height - height_1;
if(x < 0){
x = widthDiff / 2;
}else if(x > widthDiff){
x = widthDiff;
}
if(y < 0){
y = heightDiff / 2;
}else if(y > heightDiff){
y = heightDiff;
}
g.drawImage(waterImage, x, y, width_1, height_1, null); // 水印文件结束
g.dispose();
ImageIO.write(bufferedImage, PICTRUE_FORMATE_JPG, out);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 添加文字水印
* @param src 原始图片输入流
* @param out 成品图片输出流
* @param waterText 水印文字， 如：夏老师V5
* @param fontName 字体名称， 如：宋体&##124;微软雅黑&##124;楷体&##124;...
* @param fontStyle 字体样式：Font.BOLD&##124;Font.ITALIC&##124;...
* @param fontSize 字体大小，单位为像素
* @param color 字体颜色
* @param x 水印文字距离目标图片左侧的偏移量，如果x<0, 则在正中间
* @param y 水印文字距离目标图片上侧的偏移量，如果y<0, 则在正中间
* @param alpha 水印透明度(0.0 -- 1.0, 0.0为完全透明，1.0为完全不透明)
*/
public static void watermark(InputStream src,OutputStream out, String waterText, String fontName, int fontStyle, int fontSize, Color color, int x, int y, float alpha) {
try {
Image image = ImageIO.read(src);
int width = image.getWidth(null);
int height = image.getHeight(null);
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bufferedImage.createGraphics();
g.drawImage(image, 0, 0, width, height, null);
g.setFont(new Font(fontName, fontStyle, fontSize));
g.setColor(color);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));
int width_1 = fontSize * getLength(waterText);
int height_1 = fontSize;
int widthDiff = width - width_1;
int heightDiff = height - height_1;
if(x < 0){
x = widthDiff / 2;
}else if(x > widthDiff){
x = widthDiff;
}
if(y < 0){
y = heightDiff / 2;
}else if(y > heightDiff){
y = heightDiff;
}
g.drawString(waterText, x, y + height_1);
g.dispose();
ImageIO.write(bufferedImage, PICTRUE_FORMATE_JPG, out);
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 获取字符长度，一个汉字作为 1 个字符, 一个英文字母作为 0.5 个字符
* @param text
* @return 字符长度，如：text="中国",返回 2；text="test",返回 2；text="中国ABC",返回 4.
*/
public static int getLength(String text) {
int textLength = text.length();
int length = textLength;
for (int i = 0; i < textLength; i++) {
if (String.valueOf(text.charAt(i)).getBytes().length > 1) {
length++;
}
}
return (length % 2 == 0) ? length / 2 : length / 2 + 1;
}
/**
* 图片缩放
* @param src 原始图片输入流
* @param out 成品图片输出流
* @param height 缩放后的高度
* @param width 缩放后的宽度
* @param bb 比例不对时是否需要补白
*/
public static void resize(InputStream src,OutputStream out, int height, int width, boolean bb) {
try {
double ratio = 0; //缩放比例
BufferedImage bi = ImageIO.read(src);
Image itemp = bi.getScaledInstance(width, height, BufferedImage.SCALE_SMOOTH);
//计算比例
if ((bi.getHeight() > height) &##124;&##124; (bi.getWidth() > width)) {
if (bi.getHeight() > bi.getWidth()) {
ratio = (new Integer(height)).doubleValue() / bi.getHeight();
} else {
ratio = (new Integer(width)).doubleValue() / bi.getWidth();
}
AffineTransformOp op = new AffineTransformOp(AffineTransform.getScaleInstance(ratio, ratio), null);
itemp = op.filter(bi, null);
}
if (bb) {
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.setColor(Color.white);
g.fillRect(0, 0, width, height);
if (width == itemp.getWidth(null))
g.drawImage(itemp, 0, (height - itemp.getHeight(null)) / 2, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);
else
g.drawImage(itemp, (width - itemp.getWidth(null)) / 2, 0, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);
g.dispose();
itemp = image;
}
ImageIO.write((BufferedImage) itemp, "jpg",out);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 对图片文件进行Base64编码，并加上DataURI前缀，可以直接在HTML中使用
* @param imageFile
* @return
* @throws IOException
*/
public static String base64EncodeAsDataURI(File imageFile) throws IOException{
return "data:image/png;base64,"+base64Encode(imageFile);
}
/**
* 对图片文件进行Base64编码
* @param imageFile
* @return
* @throws IOException
*/
public static String base64Encode(File imageFile) throws IOException{
byte[] data = FileUtils.readFileToByteArray(imageFile);
return base64Encode(data);
}
/**
* 对图片文件进行Base64编码
* @param image
* @return
* @throws IOException
*/
public static String base64Encode(byte[] image) throws IOException{
return Base64.encodeBase64String(image);
}
/**
* 对图片文件进行Base64编码
* @param fileAbsPath
* @return
* @throws IOException
*/
public static String base64Encode(String fileAbsPath) throws IOException{
return base64Encode(new File(fileAbsPath));
}
/**
* 对图片文件进行Base64编码
* @param image
* @return
* @throws IOException
*/
public static String base64Encode(InputStream image) throws IOException{
ByteArrayOutputStream output = new ByteArrayOutputStream();
IOUtils.copy(image, output);
return base64Encode(output.toByteArray());
}
/**
* 把Base64解码为byte[]，然后写到输出流
* @param imgStr 转换为图片的字符串
* @param imgCreatePath 将64编码生成图片的路径
* @throws IOException
*/
public static void base64Decode(String imgData, OutputStream out) throws IOException{
byte[] b = Base64.decodeBase64(imgData);
out.write(b);out.close();
}
/**
* 把Base64解码为byte[]，然后写到文件中
* @param imgData
* @param out
* @throws IOException
*/
public static void base64Decode(String imgData, File file) throws IOException{
base64Decode(imgData, new FileOutputStream(file));
}
/**
* 把Base64解码为byte[]，然后写到文件中
* @param imgData
* @param outAbsPath
* @throws IOException
*/
public static void base64Decode(String imgData, String fileAbsPath) throws IOException{
base64Decode(imgData, new FileOutputStream(fileAbsPath));
}
public static void main(String[] args) throws IOException {
/* 文字水印 */
File file = new File("d:/abc/mpt8_2013122423341787.jpg");
InputStream in = new FileInputStream(file);
OutputStream out = new FileOutputStream("d:/abc/hello.jpg");
watermark(in, out, "HelloWorld", "宋体", Font.BOLD, 72, Color.WHITE,100, 100, 0.5f);
}
}
```