Java图片工具类
该图片工具类功能：校验图片比例、图片压缩、图片转码为Base64、Base64字符串转化成图片、把图片路径转码、人脸切图(只适用于百度人脸检测接口返回的坐标点)、图片Base64解码并输出流、图片Base64编码转成输入流。
package com.blog.chen_2890.utils;
import net.coobird.thumbnailator.Thumbnails;
import org.apache.tomcat.util.codec.binary.Base64;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.URLEncoder;
/**
* @description 图片工具类
* @date 2019/5/7 15:01
* @author https://blog.csdn.net/chen_2890
*/
public class ImgUtils {
/**
* @description 校验图片比例
* @param file 图片
* @param imageWidth 宽
* @param imageHeight 高
* @return boolean true：符合要求
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:13
* @version V1.0
*/
public static boolean checkImageScale(File file, int imageWidth, int imageHeight) throws IOException {
Boolean result = false;
if (!file.exists()) {
return false;
}
BufferedImage bufferedImage = ImageIO.read(file);
int width = bufferedImage.getWidth();
int height = bufferedImage.getHeight();
if (imageHeight != 0 && height != 0) {
int scale1 = imageHeight / imageWidth;
int scale2 = height / width;
if (scale1 == scale2) {
result = true;
}
}
return result;
}
/**
* @description 图片压缩
* @param inputPath 原始图片路径
* @param outputPath 输出图片路径
* @param oldWidth 压缩前宽度
* @param oldHeight 压缩前高度
* @param newWidth 压缩后宽度
* @param newHeight 压缩后高度
* @return void
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:12
* @version V1.0
*/
public static void imgCompress(String inputPath, String outputPath, Double oldWidth, Double oldHeight, Double newWidth, Double newHeight) throws IOException {
//将自定义宽高转换成对应比例
double widthScale = newWidth / oldWidth;
double heightScale = newHeight / oldHeight;
//压缩
Thumbnails.of(inputPath)
.scale(widthScale, heightScale)
.outputQuality(1d)
.toFile(outputPath);
}
/**
* @description 将图片文件转化为字节数组字符串，并对其进行Base64编码处理
* @param path 图片路径
* @return java.lang.String base64字符串
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:11
* @version V1.0
*/
public static String imgToBase64(String path) throws IOException {
byte[] data = null;
// 读取图片字节数组
InputStream in = null;
try {
in = new FileInputStream(path);
data = new byte[in.available()];
in.read(data);
} finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
//返回Base64编码过的字节数组字符串
return Base64.encodeBase64String(data);
}
/**
* @description 把图片路径转码
* @param path 图片路径
* @return java.lang.String
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:08
* @version V1.0
*/
public static String URLEncoder(String path) {
try {
path = URLEncoder.encode(path, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return path;
}
/**
*
*
* @description 人脸切图(只适用于百度人脸检测接口返回的坐标点)
* @param imgBase64 图片Base64编码
* @param x 人脸区域离左边界的距离
* @param y 人脸区域离上边界的距离
* @param width 人脸区域的宽度
* @param height 人脸区域的高度
* @return java.lang.String 切脸后Base64编码
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:07
* @version V1.0
*/
public static String cut(String imgBase64, double x, double y, double width, double height) throws IOException {
//将浮点数转换成整型，由于百度人脸检测接口返回的y轴是眉毛位置的坐标点
//因此需要把坐标点向头顶位置偏移，所以对坐标点进行修改，偏移量目前暂定为这些，后续可根据具体情况变更
int xInt = new Double(Math.floor(x)).intValue() - 10;
int yInt = new Double(Math.floor(y)).intValue() - 50;
int widthInt = new Double(Math.ceil(width)).intValue() + 20;
int heightInt = new Double(Math.ceil(height)).intValue() + 50;
//切图
InputStream inputStream = imgBase64ToInput(imgBase64);
BufferedImage bufferedImage = Thumbnails.of(inputStream)
.sourceRegion(xInt, yInt, widthInt, heightInt)
.size(widthInt, heightInt)
.outputQuality(1d)
.asBufferedImage();
//转base64
BASE64Encoder encoder = new BASE64Encoder();
//io流
ByteArrayOutputStream baos = new ByteArrayOutputStream();
//写入流中
ImageIO.write(bufferedImage, "jpg", baos);
//转换成字节数组
byte[] bytes = baos.toByteArray();
//转换成base64串
String newImgBase64 = encoder.encodeBuffer(bytes).trim();
//删除 \r\n，注意：转换成base64串时，一定要删除\r和\n
String newImg = newImgBase64.replaceAll("\n", "").replaceAll("\r", "");
return newImg;
}
/**
* @description 处理Base64解码并输出流
* @param base64 图片Base64编码
* @param out OutputStream
* @return boolean
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:06
* @version V1.0
*/
public static boolean base64ToImgOutput(String base64, OutputStream out) throws IOException {
// 图像数据为空
if (base64 == null) {
return false;
}
try {
// Base64解码
byte[] bytes = org.apache.commons.codec.binary.Base64.decodeBase64(base64);
for (int i = 0; i < bytes.length; ++i) {
// 调整异常数据
if (bytes[i] < 0) {
bytes[i] += 256;
}
}
//生成jpeg图片
out.write(bytes);
out.flush();
return true;
} finally {
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* @description 图片Base64编码转成输入流
* @param imgBase64 图片Base64编码
* @return java.io.InputStream
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:04
* @version V1.0
*/
public static InputStream imgBase64ToInput(String imgBase64) {
ByteArrayInputStream stream = null;
try {
BASE64Decoder decoder = new BASE64Decoder();
byte[] bytes1 = decoder.decodeBuffer(imgBase64);
stream = new ByteArrayInputStream(bytes1);
} catch (Exception e) {
e.printStackTrace();
}
return stream;
}
/**
* @description base64字符串转化成图片
* @param imgBase64 base64字符串
* @param imgPath 图片路径(绝对路径)
* @return boolean
* @author https://blog.csdn.net/chen_2890
* @date 2019/5/18 20:02
* @version V1.0
*/
public static boolean imgBase64ToImage(String imgBase64,String imgPath){
//图像数据为空
if(imgBase64 == null){
return false;
}
BASE64Decoder decoder = new BASE64Decoder();
try {
//Base64解码
byte[] b = decoder.decodeBuffer(imgBase64);
for(int i=0;i<b.length;++i){
if(b[i]<0){
//调整异常数据
b[i]+=256;
}
}
//生成图片
OutputStream out = new FileOutputStream(imgPath);
out.write(b);
out.flush();
out.close();
return true;
}catch (Exception e){
e.printStackTrace();
}
return false;
}
}
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