最近在做关于社交项目时，用到了二维码中间带图片logo的功能，但是要求图片为圆形，于是找到了java剪裁图片为圆形的工具类，并同时在圆形外围带有白边，不多说，直接上代码：
代码语言：javascript复制package com.im.app.api.util;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.Ellipse2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.net.URL;
/**
* @Author: EDZ
* @Description: ${description}
* @Date: 2019/5/9 13:05
* @Version: 1.0
*/
public class CopeImageUtil {
public static BufferedImage cutHeadImages(String headUrl) {
BufferedImage avatarImage = null;
try {
avatarImage = ImageIO.read(new URL(headUrl));
avatarImage = scaleByPercentage(avatarImage, avatarImage.getWidth(), avatarImage.getWidth());
int width = avatarImage.getWidth();
// 透明底的图片
BufferedImage formatAvatarImage = new BufferedImage(width, width, BufferedImage.TYPE_4BYTE_ABGR);
Graphics2D graphics = formatAvatarImage.createGraphics();
//把图片切成一个园
graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
//留一个像素的空白区域，这个很重要，画圆的时候把这个覆盖
int border = 1;
//图片是一个圆型
Ellipse2D.Double shape = new Ellipse2D.Double(border, border, width - border * 2, width - border * 2);
//需要保留的区域
graphics.setClip(shape);
graphics.drawImage(avatarImage, border, border, width - border * 2, width - border * 2, null);
graphics.dispose();
//在圆图外面再画一个圆
//新创建一个graphics，这样画的圆不会有锯齿
graphics = formatAvatarImage.createGraphics();
graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int border1 = 3;
//画笔是4.5个像素，BasicStroke的使用可以查看下面的参考文档
//使画笔时基本会像外延伸一定像素，具体可以自己使用的时候测试
Stroke s = new BasicStroke(5F, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND);
graphics.setStroke(s);
graphics.setColor(Color.WHITE);
graphics.drawOval(border1, border1, width - border1 * 2, width - border1 * 2);
graphics.dispose();
OutputStream os = new FileOutputStream("C:\Users\EDZ\Desktop\剪裁图片\13000.png");//发布项目时，如：Tomcat 他会在服务器本地tomcat webapps文件下创建此文件名
ImageIO.write(formatAvatarImage, "PNG", os);
return formatAvatarImage;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 缩小Image，此方法返回源图像按给定宽度、高度限制下缩放后的图像
*
* @param inputImage
* ：压缩后宽度
* ：压缩后高度
* @throws java.io.IOException
* return
*/
public static BufferedImage scaleByPercentage(BufferedImage inputImage, int newWidth, int newHeight){
// 获取原始图像透明度类型
try {
int type = inputImage.getColorModel().getTransparency();
int width = inputImage.getWidth();
int height = inputImage.getHeight();
// 开启抗锯齿
RenderingHints renderingHints = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
// 使用高质量压缩
renderingHints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
BufferedImage img = new BufferedImage(newWidth, newHeight, type);
Graphics2D graphics2d = img.createGraphics();
graphics2d.setRenderingHints(renderingHints);
graphics2d.drawImage(inputImage, 0, 0, newWidth, newHeight, 0, 0, width, height, null);
graphics2d.dispose();
return img;
}catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static void main(String[] args) throws Exception {
cutHeadImages("https://mjmall.oss-cn-shanghai.aliyuncs.com/18/1/merchantIcon.png");
}
}如图：
