I was looking for a script that will resize the image automatically . This script resize the image . Here u have to supply a fixed value of width and i’ll resize the image .

<?php

// This is the temporary file created by PHP
$uploadedfile = $_FILES['uploadfile']['tmp_name'];

// Create an Image from it so we can do the resize
$src = imagecreatefromjpeg($uploadedfile);

// Capture the original size of the uploaded image
list($width,$height)=getimagesize($uploadedfile);

$newwidth=600;
$newheight=($height/$width)*600;
$tmp=imagecreatetruecolor($newwidth,$newheight);

// this line actually does the image resizing, copying from the original
// image into the $tmp image
imagecopyresampled($tmp,$src,0,0,0,0,$newwidth,$newheight,$width,$height);

// now write the resized image to disk. I have assumed that you want the
// resized, uploaded image file to reside in the ./images subdirectory.
$filename = “images/”. $_FILES['uploadfile']['name'];
imagejpeg($tmp,$filename,100);

imagedestroy($src);
imagedestroy($tmp); // NOTE: PHP will clean up the temp file it created when the request
// has completed.
?>

Note : I found the script here