How to use php to handle the compression function of multiple image uploads-PHP Tutorial-php.cn

This article mainly introduces the function of php processing multi-image upload compression code. It is very good and has certain reference value. Friends who need it can refer to it

I read some information online about processing image compression , most of the ones I found were single-image compression, either single front-end or back-end, so I adjusted the front-end and front-end compression myself, and supported multi-image compressed image instances. There is a lot of code, it will be clearer if you copy it directly to the editor

1. First create a simple upload page upload.php. First compress the image through the front-end code, and directly upload the code

<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no, minimal-ui">
  <title>实名验证</title>
  <script type="text/javascript">
    /*
    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
    objp：一个是容器或者回调函数
    photoCompress()
     */
    function photoCompress(file,w,objp){
      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,objp)
      }
    }
    function canvasDataURL(path, obj, callback){
      var img = new Image();
      img.src = path;
      img.onload = function(){
        var that = this;
        // 默认按比例压缩
        var w = that.width,
          h = that.height,
          scale = w / h;
        w = obj.width || w;
        h = obj.height || (w / scale);
        var quality = 0.7; // 默认图片质量为0.7
        //生成canvas
        var canvas = document.createElement(&#39;canvas&#39;);
        var ctx = canvas.getContext(&#39;2d&#39;);
        // 创建属性节点
        var anw = document.createAttribute("width");
        anw.nodeValue = w;
        var anh = document.createAttribute("height");
        anh.nodeValue = h;
        canvas.setAttributeNode(anw);
        canvas.setAttributeNode(anh);
        ctx.drawImage(that, 0, 0, w, h);
        // 图像质量
        if(obj.quality && obj.quality <= 1 && obj.quality > 0){
          quality = obj.quality;
        }
        // quality值越小，所绘制出的图像越模糊
        var base64 = canvas.toDataURL(&#39;image/jpeg&#39;, quality);
        // 回调函数返回base64的值
        callback(base64);
      }
    }
    /**
     * 将以base64的图片url数据转换为Blob
     * @param urlData
     * 用url方式表示的base64图片数据
     */
    function convertBase64UrlToBlob(urlData){
      var arr = urlData.split(&#39;,&#39;), mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
      while(n--){
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new Blob([u8arr], {type:mime});
    }
    var xhr;
    //上传文件方法
    function uploadClick() {
      document.getElementsByClassName("uploadbtn")[0].value = &#39;上传中...&#39;;
      document.getElementsByClassName("uploadbtn")[0].disabled=true; 
      var obj = document.getElementsByClassName("myfile");
      for(var i=0;i<2;i++){
        UploadFile(obj[i].files[0],&#39;file&#39;+i);
      }
    }
    function UploadFile(fileObj,filed){
      var shopid = document.getElementById(&#39;shopid&#39;).value;
      var adminid = document.getElementById(&#39;adminid&#39;).value;
      var url = "newshimingupload.php"; // 接收上传文件的后台地址 
      var form = new FormData(); // FormData 对象
      if(fileObj.size/1024 > 100) { //大于100k，进行压缩上传
        photoCompress(fileObj, {
          quality: 0.2
        }, function(base64Codes){
          //console.log("压缩后：" + base.length / 1024 + " " + base);
          var bl = convertBase64UrlToBlob(base64Codes);
          form.append("file", bl, "file_"+Date.parse(new Date())+".jpg"); // 文件对象
          form.append("shopid", shopid); // 文件对象
          form.append("adminid", adminid); // 文件对象
          form.append("filed", filed); // 文件对象
          xhr = new XMLHttpRequest(); // XMLHttpRequest 对象
          xhr.open("post", url, false); //post方式，url为服务器请求地址，true 该参数规定请求是否异步处理。
          xhr.onload = uploadComplete; //请求完成
          xhr.onerror = uploadFailed; //请求失败
          // xhr.upload.onprogress = progressFunction;//【上传进度调用方法实现】
          xhr.upload.onloadstart = function(){//上传开始执行方法
            ot = new Date().getTime();  //设置上传开始时间
            oloaded = 0;//设置上传开始时，以上传的文件大小为0
          };
          xhr.send(form); //开始上传，发送form数据
        });
      }else{ //小于等于1M 原图上传
        form.append("file", fileObj); // 文件对象
        form.append("shopid", shopid); // 文件对象
        form.append("adminid", adminid); // 文件对象
        form.append("filed", filed); // 文件对象
        xhr = new XMLHttpRequest(); // XMLHttpRequest 对象
        xhr.open("post", url, false); //post方式，url为服务器请求地址，true 该参数规定请求是否异步处理。
        xhr.onload = uploadComplete; //请求完成
        xhr.onerror = uploadFailed; //请求失败
        xhr.upload.onloadstart = function(){//上传开始执行方法
          ot = new Date().getTime();  //设置上传开始时间
          oloaded = 0;//设置上传开始时，以上传的文件大小为0
        };
        xhr.send(form); //开始上传，发送form数据
      }
    }
    //上传成功响应
    function uploadComplete(evt) {
      //服务断接收完文件返回的结果
      var data = JSON.parse(evt.target.responseText);
      console.log(data);
      if(data.status){
        alert(data.msg);
        if(data.msg == &#39;门店照上传成功&#39;){
          window.location.href = "/dd_admin/index.php";
        }
      }
    }
    //上传失败
    function uploadFailed(evt) {
      alert("网络不稳定，请重新上传！");
    }
  </script>
</head>
<body>
  <style type="text/css">
    .main{text-align: center;padding-top: 50px;}
    .main .myfile{margin-bottom: 15px;}
  </style>
<p class="main">
  营业执照：
  <input type="file" class="myfile" id="file1" name="file1" accept="image/x-png, image/jpg, image/jpeg, image/gif"/><br>
  门店照：
  <input type="file" class="myfile" id="file2" name="file2" accept="image/x-png, image/jpg, image/jpeg, image/gif"/><br>
  <input type="hidden" id="shopid" name="shopid" value="<?php echo $_GET[&#39;shopid&#39;]; ?>" maxlength="15">
  <input type="hidden" id="adminid" name="adminid" value="<?php echo $_GET[&#39;adminid&#39;]; ?>" maxlength="15">
  <input style="margin-top: 25px;" class="uploadbtn" type="button" onclick="uploadClick()" value="上传" /><br>
</p>
</body>
</html>
2、前端图片压缩后，请求到自定义的接口upload_deal.php.代码如下
<?php
require_once(&#39;public_func.php&#39;);
  actionUpload(&#39;uploads/&#39;,&#39;file&#39;); //参数分别代表图片存储的路径和上传的文件名
}
3、在第二部引入public_func.php,这块代码主要是对后端处理图片压缩
function actionUpload($path = &#39;/uploads/&#39;,$filename=&#39;myFile&#39;)
  {
    // $path = &#39;uploads/&#39;;  //图片存放根目录 根据自己项目路径而定
    $file = $_FILES[$filename][&#39;name&#39;];
    $folder = $path.date(&#39;Ymd&#39;)."/";
    $pre = rand(999,9999).time();
    $ext = strrchr($file,&#39;.&#39;);
    $newName = $pre.$ext;
    $out = array(
      &#39;msg&#39;=>&#39;&#39;,
      &#39;status&#39;=>&#39;error&#39;,
      &#39;img_url&#39;=>&#39;&#39;
    );
    if(!is_dir($folder))
    {
      if(!mkdir($folder, 0777, true)){
        $out[&#39;msg&#39;] = &#39;图片目录创建失败！&#39;;
        echo json_encode($out);
        exit;
      }
    }
    $im = $_FILES[$filename][&#39;tmp_name&#39;]; //上传图片资源
    $maxwidth="1056"; //设置图片的最大宽度
    $maxheight="500"; //设置图片的最大高度
    $imgname = $folder.$newName; //图片存放路径 根据自己图片路径而定
    $filetype=$_FILES[$filename][&#39;type&#39;];//图片类型
    $result = thumbImage($im,$maxwidth,$maxheight,$imgname,$filetype);
    if($result){
      $out[&#39;msg&#39;] = &#39;图片上传成功&#39;;
      $out[&#39;status&#39;] = &#39;success&#39;;
      $out[&#39;img_url&#39;] = $folder.$newName;
    }else{
      $out[&#39;msg&#39;] = &#39;图片上传失败&#39;;
    }
    return json_encode($out);
    exit;
  }
  //压缩图片
  function thumbImage($im,$maxwidth,$maxheight,$name,$filetype)
  {
    switch ($filetype) {   
      case &#39;image/pjpeg&#39;:   
      case &#39;image/jpeg&#39;:   
        $im = imagecreatefromjpeg($im);  //PHP图片处理系统函数
        break;   
      case &#39;image/gif&#39;:   
        $im = imagecreatefromgif($im);  
        break;   
      case &#39;image/png&#39;:   
        $im = imagecreatefrompng($im);  
        break;
      case &#39;image/wbmp&#39;:   
        $im = imagecreatefromwbmp($im);  
        break;       
    } 
    $resizewidth_tag = $resizeheight_tag = false;
    $pic_width = imagesx($im);
    $pic_height = imagesy($im);
    if(($maxwidth && $pic_width > $maxwidth) || ($maxheight && $pic_height > $maxheight))
    {
  $resizewidth_tag = $resizeheight_tag = false;
      if($maxwidth && $pic_width>$maxwidth)
      {
        $widthratio = $maxwidth / $pic_width;
        $resizewidth_tag = true;
      }
      if($maxheight && $pic_height>$maxheight)
      {
        $heightratio = $maxheight / $pic_height;
        $resizeheight_tag = true;
      }
      if($resizewidth_tag && $resizeheight_tag)
      {
        if($widthratio < $heightratio)
         $ratio = $widthratio;
        else
         $ratio = $heightratio;
      }
      if($resizewidth_tag && !$resizeheight_tag)
      $ratio = $widthratio;
      if($resizeheight_tag && !$resizewidth_tag)
      $ratio = $heightratio;
      $newwidth = $pic_width * $ratio;
      $newheight = $pic_height * $ratio;
      if(function_exists("imagecopyresampled"))
      {
        $newim = imagecreatetruecolor($newwidth,$newheight);//PHP图片处理系统函数
        imagecopyresampled($newim,$im,0,0,0,0,$newwidth,$newheight,$pic_width,$pic_height);//PHP图片处理系统函数
      }
      else
      {
        $newim = imagecreate($newwidth,$newheight);
        imagecopyresized($newim,$im,0,0,0,0,$newwidth,$newheight,$pic_width,$pic_height);
      }
      switch ($filetype) {   
        case &#39;image/pjpeg&#39; :   
        case &#39;image/jpeg&#39; :   
          $result = imagejpeg($newim,$name);  
          break;   
        case &#39;image/gif&#39; :   
          $result = imagegif($newim,$name);  
          break;   
        case &#39;image/png&#39; :   
          $result = imagepng($newim,$name);  
          break;
        case &#39;image/wbmp&#39; :   
          $result = imagewbmp($newim,$name);  
          break;       
      } 
      imagedestroy($newim);
    }
    else
    {
      switch ($filetype) {   
        case &#39;image/pjpeg&#39; :   
        case &#39;image/jpeg&#39; :   
          $result = imagejpeg($im,$name);  
          break;   
        case &#39;image/gif&#39; :   
          $result = imagegif($im,$name);  
          break;   
        case &#39;image/png&#39; :   
          $result = imagepng($im,$name);  
          break;
        case &#39;image/wbmp&#39; :   
          $result = imagewbmp($im,$name);  
          break;       
      }
    }
    return $result; 
  }

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