Home >Backend Development >PHP Tutorial >How to use php to handle the compression function of multiple image uploads
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('canvas');
var ctx = canvas.getContext('2d');
// 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('image/jpeg', 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(','), 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 = '上传中...';
document.getElementsByClassName("uploadbtn")[0].disabled=true;
var obj = document.getElementsByClassName("myfile");
for(var i=0;i<2;i++){
UploadFile(obj[i].files[0],'file'+i);
}
}
function UploadFile(fileObj,filed){
var shopid = document.getElementById('shopid').value;
var adminid = document.getElementById('adminid').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 == '门店照上传成功'){
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['shopid']; ?>" maxlength="15">
<input type="hidden" id="adminid" name="adminid" value="<?php echo $_GET['adminid']; ?>" maxlength="15">
<input style="margin-top: 25px;" class="uploadbtn" type="button" onclick="uploadClick()" value="上传" /><br>
</p>
</body>
</html>
2、前端图片压缩后，请求到自定义的接口upload_deal.php.代码如下
<?php
require_once('public_func.php');
actionUpload('uploads/','file'); //参数分别代表图片存储的路径和上传的文件名
}
3、在第二部引入public_func.php,这块代码主要是对后端处理图片压缩
function actionUpload($path = '/uploads/',$filename='myFile')
{
// $path = 'uploads/'; //图片存放根目录 根据自己项目路径而定
$file = $_FILES[$filename]['name'];
$folder = $path.date('Ymd')."/";
$pre = rand(999,9999).time();
$ext = strrchr($file,'.');
$newName = $pre.$ext;
$out = array(
'msg'=>'',
'status'=>'error',
'img_url'=>''
);
if(!is_dir($folder))
{
if(!mkdir($folder, 0777, true)){
$out['msg'] = '图片目录创建失败！';
echo json_encode($out);
exit;
}
}
$im = $_FILES[$filename]['tmp_name']; //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]['type'];//图片类型
$result = thumbImage($im,$maxwidth,$maxheight,$imgname,$filetype);
if($result){
$out['msg'] = '图片上传成功';
$out['status'] = 'success';
$out['img_url'] = $folder.$newName;
}else{
$out['msg'] = '图片上传失败';
}
return json_encode($out);
exit;
}
//压缩图片
function thumbImage($im,$maxwidth,$maxheight,$name,$filetype)
{
switch ($filetype) {
case 'image/pjpeg':
case 'image/jpeg':
$im = imagecreatefromjpeg($im); //PHP图片处理系统函数
break;
case 'image/gif':
$im = imagecreatefromgif($im);
break;
case 'image/png':
$im = imagecreatefrompng($im);
break;
case 'image/wbmp':
$im = imagecreatefromwbmp($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 'image/pjpeg' :
case 'image/jpeg' :
$result = imagejpeg($newim,$name);
break;
case 'image/gif' :
$result = imagegif($newim,$name);
break;
case 'image/png' :
$result = imagepng($newim,$name);
break;
case 'image/wbmp' :
$result = imagewbmp($newim,$name);
break;
}
imagedestroy($newim);
}
else
{
switch ($filetype) {
case 'image/pjpeg' :
case 'image/jpeg' :
$result = imagejpeg($im,$name);
break;
case 'image/gif' :
$result = imagegif($im,$name);
break;
case 'image/png' :
$result = imagepng($im,$name);
break;
case 'image/wbmp' :
$result = imagewbmp($im,$name);
break;
}
}
return $result;
}
. The above is the entire content of this article. I hope it will be helpful to everyone's study. For more related content, please Follow PHP Chinese website!
Related recommendations:
How to generate promotional posters with PHP
##Use PHP to achieve the function of top articles
Code for exporting data and pictures using PHPEXCEL
The above is the detailed content of How to use php to handle the compression function of multiple image uploads. For more information, please follow other related articles on the PHP Chinese website!