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:
代码语言:javascript复制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:
代码语言:javascript复制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"));
}
}