java input 调用手机相机和本地照片上传图片到服务器然后压缩的方法

<input type="file" accept="image/*" capture="camera">

<input type="file" accept="video/*" capture="camcorder">

<input type="file" accept="audio/*" capture="microphone">

<input type="file" accept="image/*" multiple>

<form id="uploadForm" class="mui-input-group"  action="/jxs/uploadtou.do" method="post" enctype="multipart/form-data" >
  <div class="mui-input-row">
   <label>图片</label>
   <input required="required" class="mui-input-clear mui-input" type="file" name="file" id="photo_pick" accept="image/*">
  </div>

  <div class="mui-content-padded" >
   <input  value="上传" type="submit">
  </div>
 </form>

<div class="progress_dialog" ></div>

<script>
 /*图片地址
 https://cache.yisu.com/upload/information/20200623/121/101839.html&fromurl=ippr_z2C%24qAzdH3FAzdH3Fooo_z%26e3Bkzcc_z%26e3Bv54AzdH3F4jtgektzitAzdH3F8l9c9_z%26e3Bip4s&gsm=0&rpstart=0&rpnum=0
 */
 $(function() {
  $("#photo_pick").on("change", function () {
   var file = this.files[0];
   photoCompress(file, 50, $(".progress_dialog")[0])
   $(".progress_dialog").show();
   if (!this.files.length) return;
   var files = Array.prototype.slice.call(this.files);
   if (files.length > 9) {
    alert("最多同时只可上传9张图片");
    return;
   }
  /* files.forEach(function (file, i) {
    /!*var reader = new FileReader();
    reader.onload = function () {
     var imgO = document.createElement("img");
     imgO.src = reader.result;
    }*!/
    reader.readAsDataURL(file);
    $(".progress_dialog").hide();*/
   });
  })


  /*
 三个参数
 file：一个是文件(类型是图片格式)，
 w：一个是文件压缩的后宽度，宽度越小，字节越小
 objDiv：一个是容器或者回调函数
 photoCompress()
  */
  function photoCompress(file, w, objDiv) {
   var ready = new FileReader();
   /*开始读取指定的Blob对象或File对象中的内容. 当读取操作完成时,readyState属性的值会成为DONE,如果设置了onloadend事件处理程序,则调用之.同时,result属性中将包含一个data: URL格式的字符串以表示所读取文件的内容.*/
   ready.readAsDataURL(file);
   ready.onload = function () {
    var re = this.result;
    canvasDataURL(re, w, objDiv)

   }
  }

  function canvasDataURL(re, w, objDiv) {
   var newImg = new Image();
   newImg.src = re;
   var imgWidth, imgHeight, offsetX = 0, offsetY = 0;
   newImg.onload = function () {
    var img = document.createElement("img");
    img.src = newImg.src;
    imgWidth = img.width;
    imgHeight = img.height;
    var canvas = document.createElement("canvas");
    canvas.width = w;
    canvas.height = w;
    var ctx = canvas.getContext("2d");
    ctx.clearRect(0, 0, w, w);
    if (imgWidth > imgHeight) {
     imgWidth = w * imgWidth / imgHeight;
     imgHeight = w;
     offsetX = -Math.round((imgWidth - w) / 6);
    } else {
     imgHeight = w * imgHeight / imgWidth;
     imgWidth = w;
     offsetY = -Math.round((imgHeight - w) / 6);
    }
    ctx.drawImage(img, offsetX, offsetY, imgWidth, imgHeight);
    var base64 = canvas.toDataURL("image/jpeg", 0.1);
    if (typeof objDiv == "object") {
     objDiv.appendChild(canvas);
    } else if (typeof objDiv == "function") {
     objDiv(base64);
    }
   }

 }
</script>

@PostMapping("/uploadtou.do")
 public String uploadtou(@RequestParam(value = "file") MultipartFile file, HttpServletRequest request) throws IOException {
  System.out.println(file);
  String result = "";
  if (!file.isEmpty()) {
   try {
    Shopuser u = (Shopuser) request.getSession().getAttribute("currentUser");
    String extName = file.getOriginalFilename();
    String fileName = file.getName();
    String suffix = extName.substring(extName.lastIndexOf(".") + 1);
    System.err.println(suffix);
    Date now = new Date();
    SimpleDateFormat outFormat = new SimpleDateFormat("yyyyMMddHHmmss");
    String s = outFormat.format(now);
    BufferedOutputStream bos = new BufferedOutputStream(
      new FileOutputStream(new File("D:\\xiangmu\\demo\\" + s + "." + suffix)));
    bos.write(file.getBytes());
    bos.flush();
    bos.close();
    /**
     * compress 图片缩放类的使用(缩略图)
     * srcImage 为InputStream对象
     * Rectangle 为需要截图的长方形坐标
     * proportion 为压缩比例
     * **/
    InputStream in = null;
    //缩放后需要保存的路径
    File saveFile = new File("D:\\xiangmu\\demo\\" + s + s + "." + suffix);
    try {
     //原图片的路径
     in = new FileInputStream(new File("D:\\xiangmu\\demo\\" + s + "." + suffix));
     int length = in.available();
     if (length / 1024 >= 10 && length / 1024 < 100) {
      if (compress(in, saveFile, 10)) {
       System.out.println("图片压缩十倍！");
      }
     } else if (length / 1024 >= 100 && length / 1024 < 1000) {
      if (compress(in, saveFile, 100)) {
       System.out.println("图片压缩100倍！");
      }
     } else if (length / 1024 >= 1000 && length / 1024 < 10000) {
      if (compress(in, saveFile, 1000)) {
       System.out.println("图片压缩1000倍！");
      }
     } else if (length / 1024 < 10 && length / 1024 > 0) {
      if (compress(in, saveFile, 1)) {
       System.out.println("图片压缩1倍！");
      }
     }

    } catch (Exception e) {
     e.printStackTrace();
    } finally {
     in.close();
    }
    String filename = "/Path/" + s + s + "." + suffix;//服务器地址
    System.out.println(filename);
    int a = shopService.updateImg(u.getId(), filename);
    System.out.println(filename);
   } catch (Exception e) {
    e.printStackTrace();
   }
  } else {
  }

  return "wode.html";
 }

package com.example.springbootshop.util;

import org.junit.Test;

import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import javax.imageio.ImageIO;





/**
 * 图片工具类，完成图片的截取
 * 所有方法返回值均未boolean型
 */
public class ImageHelper {
 /**
  * 实现图像的等比缩放
  * @param source
  * @param targetW
  * @param targetH
  * @return
  */
 private static BufferedImage resize(BufferedImage source, int targetW,
          int targetH) {
  // targetW，targetH分别表示目标长和宽
  int type = source.getType();
  BufferedImage target = null;
  double sx = (double) targetW / source.getWidth();
  double sy = (double) targetH / source.getHeight();
  // 这里想实现在targetW，targetH范围内实现等比缩放。如果不需要等比缩放
  // 则将下面的if else语句注释即可
  if (sx < sy) {
   sx = sy;
   targetW = (int) (sx * source.getWidth());
  } else {
   sy = sx;
   targetH = (int) (sy * source.getHeight());
  }
  if (type == BufferedImage.TYPE_CUSTOM) { // handmade
   ColorModel cm = source.getColorModel();
   WritableRaster raster = cm.createCompatibleWritableRaster(targetW,
     targetH);
   boolean alphaPremultiplied = cm.isAlphaPremultiplied();
   target = new BufferedImage(cm, raster, alphaPremultiplied, null);
  } else
   target = new BufferedImage(targetW, targetH, type);
  Graphics2D g = target.createGraphics();
  // smoother than exlax:
  g.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
    RenderingHints.VALUE_INTERPOLATION_BICUBIC);
  g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy));
  g.dispose();
  return target;
 }

 /**
  * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false
  * @param inFilePath 要截取文件的路径
  * @param outFilePath 截取后输出的路径
  * @param width 要截取宽度
  * @param hight 要截取的高度
  * @throws Exception
  */
 public static boolean compress(String inFilePath, String outFilePath,
         int width, int hight) {
  boolean ret = false;
  File file = new File(inFilePath);
  File saveFile = new File(outFilePath);
  InputStream in = null;
  try {
   in = new FileInputStream(file);
   ret = compress(in, saveFile, width, hight);
  } catch (FileNotFoundException e) {
   e.printStackTrace();
   ret = false;
  } finally{
   if(null != in){
    try {
     in.close();
    } catch (IOException e) {
     e.printStackTrace();
    }
   }
  }

  return ret;
 }

 /**
  * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false
  * @param in 要截取文件流
  * @param outFilePath 截取后输出的路径
  * @param width 要截取宽度
  * @param hight 要截取的高度
  * @throws Exception
  */
 public static boolean compress(InputStream in, File saveFile,
         int width, int hight) {
//  boolean ret = false;
  BufferedImage srcImage = null;
  try {
   srcImage = ImageIO.read(in);
  } catch (IOException e) {
   e.printStackTrace();
   return false;
  }

  if (width > 0 || hight > 0) {
   // 原图的大小
   int sw = srcImage.getWidth();
   int sh = srcImage.getHeight();
   // 如果原图像的大小小于要缩放的图像大小，直接将要缩放的图像复制过去
   if (sw > width && sh > hight) {
    srcImage = resize(srcImage, width, hight);
   } else {
    String fileName = saveFile.getName();
    String formatName = fileName.substring(fileName
      .lastIndexOf('.') + 1);
    try {
     ImageIO.write(srcImage, formatName, saveFile);
    } catch (IOException e) {
     e.printStackTrace();
     return false;
    }
    return true;
   }
  }
  // 缩放后的图像的宽和高
  int w = srcImage.getWidth();
  int h = srcImage.getHeight();
  // 如果缩放后的图像和要求的图像宽度一样，就对缩放的图像的高度进行截取
  if (w == width) {
   // 计算X轴坐标
   int x = 0;
   int y = h / 2 - hight / 2;
   try {
    saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
   } catch (IOException e) {
    e.printStackTrace();
    return false;
   }
  }
  // 否则如果是缩放后的图像的高度和要求的图像高度一样，就对缩放后的图像的宽度进行截取
  else if (h == hight) {
   // 计算X轴坐标
   int x = w / 2 - width / 2;
   int y = 0;
   try {
    saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
   } catch (IOException e) {
    e.printStackTrace();
    return false;
   }
  }

  return true;
 }

 /**
  * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false
  * @param in 图片输入流
  * @param saveFile 压缩后的图片输出流
  * @param proportion 压缩比
  * @throws Exception
  */
 public static boolean compress(InputStream in, File saveFile, int proportion) {
  if(null == in
    ||null == saveFile
    ||proportion < 1){// 检查参数有效性
   //LoggerUtil.error(ImageHelper.class, "--invalid parameter, do nothing!");
   return false;
  }

  BufferedImage srcImage = null;
  try {
   srcImage = ImageIO.read(in);
  } catch (IOException e) {
   e.printStackTrace();
   return false;
  }
  // 原图的大小
  int width = srcImage.getWidth() / proportion;
  int hight = srcImage.getHeight() / proportion;

  srcImage = resize(srcImage, width, hight);

  // 缩放后的图像的宽和高
  int w = srcImage.getWidth();
  int h = srcImage.getHeight();
  // 如果缩放后的图像和要求的图像宽度一样，就对缩放的图像的高度进行截取
  if (w == width) {
   // 计算X轴坐标
   int x = 0;
   int y = h / 2 - hight / 2;
   try {
    saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
   } catch (IOException e) {
    e.printStackTrace();
    return false;
   }
  }
  // 否则如果是缩放后的图像的高度和要求的图像高度一样，就对缩放后的图像的宽度进行截取
  else if (h == hight) {
   // 计算X轴坐标
   int x = w / 2 - width / 2;
   int y = 0;
   try {
    saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
   } catch (IOException e) {
    e.printStackTrace();
    return false;
   }
  }

  return true;
 }

 /**
  * 实现缩放后的截图
  * @param image 缩放后的图像
  * @param subImageBounds 要截取的子图的范围
  * @param subImageFile 要保存的文件
  * @throws IOException
  */
 private static void saveSubImage(BufferedImage image,
          Rectangle subImageBounds, File subImageFile) throws IOException {
  if (subImageBounds.x < 0 || subImageBounds.y < 0
    || subImageBounds.width - subImageBounds.x > image.getWidth()
    || subImageBounds.height - subImageBounds.y > image.getHeight()) {
   //LoggerUtil.error(ImageHelper.class, "Bad subimage bounds");
   return;
  }
  BufferedImage subImage = image.getSubimage(subImageBounds.x,subImageBounds.y, subImageBounds.width, subImageBounds.height);
  String fileName = subImageFile.getName();
  String formatName = fileName.substring(fileName.lastIndexOf('.') + 1);
  ImageIO.write(subImage, formatName, subImageFile);
 }


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

  /**
   * saveSubImage 截图类的使用
   * srcImage 为BufferedImage对象
   * Rectangle 为需要截图的长方形坐标
   * saveFile 需要保存的路径及名称
   * **/
  //需要截图的长方形坐标
  /*Rectangle rect =new Rectangle();
  rect.x=40;
  rect.y=40;
  rect.height=160;
  rect.width=160;

  InputStream in = null;
  //需要保存的路径及名称
  File saveFile = new File("d:\\ioc\\files\\aaa2.jpg");
  //需要进行处理的图片的路径
  in = new FileInputStream(new File("d:\\ioc\\files\\aaa.jpg"));
  BufferedImage srcImage = null;
  //将输入的数据转为BufferedImage对象
  srcImage = ImageIO.read(in);

  ImageHelper img=new ImageHelper();
  img.saveSubImage(srcImage, rect, saveFile);*/

  /**
   * compress 图片缩放类的使用(缩略图)
   * srcImage 为InputStream对象
   * Rectangle 为需要截图的长方形坐标
   * proportion 为压缩比例
   * **/
  InputStream in = null;
  //缩放后需要保存的路径
  File saveFile = new File("D:\\xiangmu\\demo\\20180523192742IMG_0049123.jpg");
  try {
   //原图片的路径
   in = new FileInputStream(new File("D:\\xiangmu\\demo\\20180523192742IMG_0049.jpg"));
   if(compress(in, saveFile, 10)){
    System.out.println("图片压缩十倍！");
   }
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   in.close();
  }
 }
}