Java实现图片无损任意角度旋转

在做项目的时候遇到一个业务需要对图片进行旋转，于是找到一个工具类，亲测有效；在此与大家共享，需要用时可以直接用哈！ 一、旋转工具类代码：

package zh.test.utils;

import java.awt.*;

import java.awt.image.BufferedImage;

/**

* 图片旋转工具类

*/

public class RotateImage {

/**

* 对图片进行旋转

*

* @param src 被旋转图片

* @param angel 旋转角度

* @return 旋转后的图片

*/

public static BufferedImage Rotate(Image src, int angel) {

int src_width = src.getWidth(null);

int src_height = src.getHeight(null);

// 计算旋转后图片的尺寸

Rectangle rect_des = CalcRotatedSize(new Rectangle(new Dimension(

src_width, src_height)), angel);

BufferedImage res = null;

res = new BufferedImage(rect_des.width, rect_des.height,

BufferedImage.TYPE_INT_RGB);

Graphics2D g2 = res.createGraphics();

// 进行转换

g2.translate((rect_des.width - src_width) / 2,

(rect_des.height - src_height) / 2);

g2.rotate(Math.toRadians(angel), src_width / 2, src_height / 2);

g2.drawImage(src, null, null);

return res;

}

/**

* 计算旋转后的图片

*

* @param src 被旋转的图片

* @param angel 旋转角度

* @return 旋转后的图片

*/

public static Rectangle CalcRotatedSize(Rectangle src, int angel) {

// 如果旋转的角度大于90度做相应的转换

if (angel >= 90) {

if (angel / 90 % 2 == 1) {

int temp = src.height;

src.height = src.width;

src.width = temp;

}

angel = angel % 90;

}

double r = Math.sqrt(src.height * src.height + src.width * src.width) / 2;

double len = 2 * Math.sin(Math.toRadians(angel) / 2) * r;

double angel_alpha = (Math.PI - Math.toRadians(angel)) / 2;

double angel_dalta_width = Math.atan((double) src.height / src.width);

double angel_dalta_height = Math.atan((double) src.width / src.height);

int len_dalta_width = (int) (len * Math.cos(Math.PI - angel_alpha

- angel_dalta_width));

int len_dalta_height = (int) (len * Math.cos(Math.PI - angel_alpha

- angel_dalta_height));

int des_width = src.width + len_dalta_width * 2;

int des_height = src.height + len_dalta_height * 2;

return new Rectangle(new Dimension(des_width, des_height));

}

}

二、调用工具类的代码：

package zh.test.controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RestController;

import org.springframework.web.multipart.MultipartFile;

import zh.test.utils.RotateImage;

import javax.imageio.ImageIO;

import java.awt.image.BufferedImage;

import java.io.File;

/**

* 测试图片旋转

*/

@RestController

@RequestMapping(value = "/test")

public class TestController {

@RequestMapping(method = RequestMethod.POST)

public void testImgRotate(MultipartFile multipartFile) throws Exception {

BufferedImage src = ImageIO.read(multipartFile.getInputStream());

//顺时针旋转90度

BufferedImage des1 = RotateImage.Rotate(src, 90);

ImageIO.write(des1, "jpg", new File("e:/90.jpg"));

//顺时针旋转180度

BufferedImage des2 = RotateImage.Rotate(src, 180);

ImageIO.write(des2, "jpg", new File("c:/180.jpg"));

//顺时针旋转270度

BufferedImage des3 = RotateImage.Rotate(src, 270);

ImageIO.write(des3, "jpg", new File("c:/270.jpg"));

}

}