本文是作者结合网上的一些资料封装的java图片处理类，支持图片的缩放，旋转，马赛克化。

不多说，上代码：

package deal;

import java.awt.Color;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.Image;

import java.awt.geom.AffineTransform;

import java.awt.image.AffineTransformOp;

import java.awt.image.BufferedImage;

import java.io.File;

import javax.imageio.ImageIO;

/**

* 图像处理类.

*

* @author nagsh

*

*/

public class ImageDeal {

String openUrl; // 原始图片打开路径

String saveUrl; // 新图保存路径

String saveName; // 新图名称

String suffix; // 新图类型 只支持gif,jpg,png

public ImageDeal(String openUrl, String saveUrl, String saveName,

String suffix) {

this.openUrl = openUrl;

this.saveName = saveName;

this.saveUrl = saveUrl;

this.suffix = suffix;

}

/**

* 图片缩放.

*

* @param width

* 需要的宽度

* @param height

* 需要的高度

* @throws Exception

*/

public void zoom(int width, int height) throws Exception {

double sx = 0.0;

double sy = 0.0;

File file = new File(openUrl);

if (!file.isFile()) {

throw new Exception("ImageDeal>>>" + file + " 不是一个图片文件!");

}

BufferedImage bi = ImageIO.read(file); // 读取该图片

// 计算x轴y轴缩放比例--如需等比例缩放，在调用之前确保参数width和height是等比例变化的

sx = (double) width / bi.getWidth();

sy = (double) height / bi.getHeight();

AffineTransformOp op = new AffineTransformOp(

AffineTransform.getScaleInstance(sx, sy), null);

File sf = new File(saveUrl, saveName + "." + suffix);

Image zoomImage = op.filter(bi, null);

try {

ImageIO.write((BufferedImage) zoomImage, suffix, sf); // 保存图片

} catch (Exception e) {

e.printStackTrace();

}

}

/**

* 旋转

*

* @param degree

* 旋转角度

* @throws Exception

*/

public void spin(int degree) throws Exception {

int swidth = 0; // 旋转后的宽度

int sheight = 0; // 旋转后的高度

int x; // 原点横坐标

int y; // 原点纵坐标

File file = new File(openUrl);

if (!file.isFile()) {

throw new Exception("ImageDeal>>>" + file + " 不是一个图片文件!");

}

BufferedImage bi = ImageIO.read(file); // 读取该图片

// 处理角度--确定旋转弧度

degree = degree % 360;

if (degree < 0)

degree = 360 + degree;// 将角度转换到0-360度之间

double theta = Math.toRadians(degree);// 将角度转为弧度

// 确定旋转后的宽和高

if (degree == 180 || degree == 0 || degree == 360) {

swidth = bi.getWidth();

sheight = bi.getHeight();

} else if (degree == 90 || degree == 270) {

sheight = bi.getWidth();

swidth = bi.getHeight();

} else {

swidth = (int) (Math.sqrt(bi.getWidth() * bi.getWidth()

+ bi.getHeight() * bi.getHeight()));

sheight = (int) (Math.sqrt(bi.getWidth() * bi.getWidth()

+ bi.getHeight() * bi.getHeight()));

}

x = (swidth / 2) - (bi.getWidth() / 2);// 确定原点坐标

y = (sheight / 2) - (bi.getHeight() / 2);

BufferedImage spinImage = new BufferedImage(swidth, sheight,

bi.getType());

// 设置图片背景颜色

Graphics2D gs = (Graphics2D) spinImage.getGraphics();

gs.setColor(Color.white);

gs.fillRect(0, 0, swidth, sheight);// 以给定颜色绘制旋转后图片的背景

AffineTransform at = new AffineTransform();

at.rotate(theta, swidth / 2, sheight / 2);// 旋转图象

at.translate(x, y);

AffineTransformOp op = new AffineTransformOp(at,

AffineTransformOp.TYPE_BICUBIC);

spinImage = op.filter(bi, spinImage);

File sf = new File(saveUrl, saveName + "." + suffix);

ImageIO.write(spinImage, suffix, sf); // 保存图片

}

/**

* 马赛克化.

* @param size 马赛克尺寸，即每个矩形的长宽

* @return

* @throws Exception

*/

public boolean mosaic(int size) throws Exception {

File file = new File(openUrl);

if (!file.isFile()) {

throw new Exception("ImageDeal>>>" + file + " 不是一个图片文件!");

}

BufferedImage bi = ImageIO.read(file); // 读取该图片

BufferedImage spinImage = new BufferedImage(bi.getWidth(),

bi.getHeight(), bi.TYPE_INT_RGB);

if (bi.getWidth() < size || bi.getHeight() < size || size <= 0) { // 马赛克格尺寸太大或太小

return false;

}

int xcount = 0; // 方向绘制个数

int ycount = 0; // y方向绘制个数

if (bi.getWidth() % size == 0) {

xcount = bi.getWidth() / size;

} else {

xcount = bi.getWidth() / size + 1;

}

if (bi.getHeight() % size == 0) {

ycount = bi.getHeight() / size;

} else {

ycount = bi.getHeight() / size + 1;

}

int x = 0; //坐标

int y = 0;

// 绘制马赛克(绘制矩形并填充颜色)

Graphics gs = spinImage.getGraphics();

for (int i = 0; i < xcount; i++) {

for (int j = 0; j < ycount; j++) {

//马赛克矩形格大小

int mwidth = size;

int mheight = size;

if(i==xcount-1){ //横向最后一个比较特殊，可能不够一个size

mwidth = bi.getWidth()-x;

}

if(j == ycount-1){ //同理

mheight =bi.getHeight()-y;

}

// 矩形颜色取中心像素点RGB值

int centerX = x;

int centerY = y;

if (mwidth % 2 == 0) {

centerX += mwidth / 2;

} else {

centerX += (mwidth - 1) / 2;

}

if (mheight % 2 == 0) {

centerY += mheight / 2;

} else {

centerY += (mheight - 1) / 2;

}

Color color = new Color(bi.getRGB(centerX, centerY));

gs.setColor(color);

gs.fillRect(x, y, mwidth, mheight);

y = y + size;// 计算下一个矩形的y坐标

}

y = 0;// 还原y坐标

x = x + size;// 计算x坐标

}

gs.dispose();

File sf = new File(saveUrl, saveName + "." + suffix);

ImageIO.write(spinImage, suffix, sf); // 保存图片

return true;

}

public static void main(String[] args) throws Exception {

ImageDeal imageDeal = new ImageDeal("e://1.jpg", "e://", "2", "jpg");

// 测试缩放

/* imageDeal.zoom(200, 300); */

// 测试旋转

/* imageDeal.spin(90); */

//测试马赛克

/*imageDeal.mosaic(4);*/

}

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持聚米学院。