imagedestroy problem

[rc726c]

could someone tell me, whats wrong with this code at below??

it gets an error_log like this:

[Wed Dec 10 02:58:05 2008] [error] [client 195.xxx.xx.32] PHP Warning: imagedestroy(): supplied argument is not a valid Image resource in /var/www/html/w/htdocs/online/duckula/fotolar/thumb.php on line 47, referer: http://www.site.com/

 

<?

 

/*

===================================

+ yThumb Class

+ Author: Yunus Emre Yilmaz

+ http://yns.zaxaz.com/ythumb.yns

===================================

*/

 

class yThumb {

       

    // find extension of file

    function find_extension($file) {

    $array = explode('.',$file);

    $key  = count($array) -1;

    $ext  = $array[$key];

    return $ext;

    }

 

    function thumb($image,$w,$h) {

    if($this->find_extension($image) == 'jpg') $image_data = imagecreatefromjpeg($image);

    if($this->find_extension($image) == 'gif') $image_data = imagecreatefromgif ($image);

    if($this->find_extension($image) == 'png') $image_data = imagecreatefrompng ($image);

   

    // Original width && height

    $width  = imagesx($image_data);

    $height = imagesy($image_data);

   

    // Control width && and height

    if(@$w > 800 || @$h > 800) {

        $w= $width; $h= $height;

    }

   

    if(@empty($w)) $w = 400;

    if(@empty($h)) $h = 600;   

 

    $new = imagecreatetruecolor($w, $h);

    imagecopyresampled($new, $image_data, 0, 0, 0, 0, $w, $h, $width, $height);

   

 

// Finally, output..

if($this->find_extension($image) == 'jpg') $image_data = imagejpeg($new);

if($this->find_extension($image) == 'gif') $image_data = imagegif ($new);

if($this->find_extension($image) == 'png') $image_data = imagepng ($new);

 

// Flush memory

imagedestroy($image_data); // line 47

imagedestroy($new);

}

 

}

 

$a = new yThumb();

$a->thumb($_GET["image"],@$_GET["w"],@$_GET["h"]);

 

 

?>

[rc726c]

i changed the bottom part of the code like this. this time, it doesnt gets an error_log.. but it doesnt work too     its not working

 

    // Finally, output..

$data = pathinfo($image);

 

switch(strtolower($data['extension']))

{

    case 'gif':

        $image_data = imagegif($new);

    break;

 

    case 'png':

        $image_data = imagepng($new);

    break;

 

    case 'jpg':

    default:

        $image_data = imagejpeg($new);

    break;

}

 

if(isset($image_data))

{

    imagedestroy($image_data);

    imagedestroy($new);

}

else

{

    die('Error processing thumbnail');

}