How to make a php image uploader script | Image Upload Script

Problem:

image upload script that change image name
Hello all.

I've got this upload script, working well.

PHP Syntax

<?php 
error_reporting(0);
 
$change="";
$abc="";
 
 
 define ("MAX_SIZE","400");
 function getExtension($str) {
         $i = strrpos($str,".");
         if (!$i) { return ""; }
         $l = strlen($str) - $i;
         $ext = substr($str,$i+1,$l);
         return $ext;
 }
 
 $errors=0;
 
 if($_SERVER["REQUEST_METHOD"] == "POST")
 {
  $image =$_FILES["file"]["name"];
 $uploadedfile = $_FILES['file']['tmp_name'];
 
 
  if ($image) 
  {
 
   $filename = stripslashes($_FILES['file']['name']);
 
    $extension = getExtension($filename);
   $extension = strtolower($extension);
 
 
 if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") && ($extension != "gif")) 
   {
 
    $change='<div class="msgdiv">Ukendt fil format.<br /><br /></div> ';
    $errors=1;
   }
   else
   {
 
 $size=filesize($_FILES['file']['tmp_name']);
 
 
if ($size > MAX_SIZE*1024)
{
 $change='<div class="msgdiv">Du har overskredet fil st&oslash;rrelsen!<br /><br /></div> ';
 $errors=1;
}
 
 
if($extension=="jpg" || $extension=="jpeg" )
{
$uploadedfile = $_FILES['file']['tmp_name'];
$src = imagecreatefromjpeg($uploadedfile);
 
}
else if($extension=="png")
{
$uploadedfile = $_FILES['file']['tmp_name'];
$src = imagecreatefrompng($uploadedfile);
 
}
else 
{
$src = imagecreatefromgif($uploadedfile);
}
 
echo $scr;
 
list($width,$height)=getimagesize($uploadedfile);
 
 
$newwidth=400;
$newheight=($height/$width)*$newwidth;
$tmp=imagecreatetruecolor($newwidth,$newheight);
 
 
$newwidth1=193;
$newheight1=143;
$tmp1=imagecreatetruecolor($newwidth1,$newheight1);
 
imagecopyresampled($tmp,$src,0,0,0,0,$newwidth,$newheight,$width,$height);
 
imagecopyresampled($tmp1,$src,0,0,0,0,$newwidth1,$newheight1,$width,$height);
 
 
$filename = "user_imgs/". $_FILES['file']['name'];
 
$filename1 = "user_imgs/thumbs/small". $_FILES['file']['name'];
 
 
 
imagejpeg($tmp,$filename,100);
 
imagejpeg($tmp1,$filename1,100);
 
imagedestroy($src);
imagedestroy($tmp);
imagedestroy($tmp1);
}}
 
}
 
//If no errors registred, print the success message
 if(isset($_POST['Submit']) && !$errors) 
 {
 
   // mysql_query("update {$prefix}users set img='$big',img_small='$small' where user_id='$user'");
  $change=' <div class="msgdiv">Billedet blev uploadet succesfuldt!<br /><br /></div>';
 }
 
?>

<?php error_reporting(0); $change=""; $abc=""; define ("MAX_SIZE","400"); function getExtension($str) { $i = strrpos($str,"."); if (!$i) { return ""; } $l = strlen($str) - $i; $ext = substr($str,$i+1,$l); return $ext; } $errors=0; if($_SERVER["REQUEST_METHOD"] == "POST") { $image =$_FILES["file"]["name"]; $uploadedfile = $_FILES['file']['tmp_name']; if ($image) { $filename = stripslashes($_FILES['file']['name']); $extension = getExtension($filename); $extension = strtolower($extension); if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") && ($extension != "gif")) { $change='<div class="msgdiv">Ukendt fil format.<br /><br /></div> '; $errors=1; } else { $size=filesize($_FILES['file']['tmp_name']); if ($size > MAX_SIZE*1024) { $change='<div class="msgdiv">Du har overskredet fil st&oslash;rrelsen!<br /><br /></div> '; $errors=1; } if($extension=="jpg" || $extension=="jpeg" ) { $uploadedfile = $_FILES['file']['tmp_name']; $src = imagecreatefromjpeg($uploadedfile); } else if($extension=="png") { $uploadedfile = $_FILES['file']['tmp_name']; $src = imagecreatefrompng($uploadedfile); } else { $src = imagecreatefromgif($uploadedfile); } echo $scr; list($width,$height)=getimagesize($uploadedfile); $newwidth=400; $newheight=($height/$width)*$newwidth; $tmp=imagecreatetruecolor($newwidth,$newheight); $newwidth1=193; $newheight1=143; $tmp1=imagecreatetruecolor($newwidth1,$newheight1); imagecopyresampled($tmp,$src,0,0,0,0,$newwidth,$newheight,$width,$height); imagecopyresampled($tmp1,$src,0,0,0,0,$newwidth1,$newheight1,$width,$height); $filename = "user_imgs/". $_FILES['file']['name']; $filename1 = "user_imgs/thumbs/small". $_FILES['file']['name']; imagejpeg($tmp,$filename,100); imagejpeg($tmp1,$filename1,100); imagedestroy($src); imagedestroy($tmp); imagedestroy($tmp1); }} } //If no errors registred, print the success message if(isset($_POST['Submit']) && !$errors) { // mysql_query("update {$prefix}users set img='$big',img_small='$small' where user_id='$user'"); $change=' <div class="msgdiv">Billedet blev uploadet succesfuldt!<br /><br /></div>'; } ?>

Problem is, when I upload 2 different images, but with the same file name, one of the images overwrites the other, I dont want that.

Can anyone help me how to generate a random name for each picture that is getting upload, so that no images contains the same file name?

[Re]

Solve:

You can use the uniqid and mt_rand functions to generate a unique string of numbers and letters that you can add to the image name.

php Syntax 

$unique = uniqid(mt_rand());
$filename = "user_imgs/{$unique}_{$_FILES['file']['name']}";
$filename1 = "user_imgs/thumbs/{$unique}_small{$_FILES['file']['name']}";

[Re]

Ah ! thank you very much.