Tip & Tricks

<?php  
$img = file_get_contents('http://www.site.com/image.jpg');

$im = imagecreatefromstring($img);

$width = imagesx($im);

$height = imagesy($im);

$newwidth = '120';

$newheight = '120';

$thumb = imagecreatetruecolor($newwidth, $newheight);

imagecopyresized($thumb, $im, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

imagejpeg($thumb,'/images/myChosenName.jpg'); //save image as jpg

imagedestroy($thumb);

imagedestroy($im);
?>

Refer:
http://stackoverflow.com/questions/9022610/download-image-from-remote-source-and-resize-then-save