problème sur image.php "Créer un portfolio de A à Z episode 4"

Salut
j'ai un problème sur le fichier image.php

code de fichier image.php

<?php ;
function resizeImage($file, $width, $height){
        # We find the right file
        $pathinfo   = pathinfo(trim($file, '/'));
        $output     = $pathinfo['dirname'] . '/' . $pathinfo['filename'] . '_' . $width . 'x' . $height . '.' . $pathinfo['extension'];
if (!file_exists($output)) {
            # Setting defaults and meta
$info                         = getimagesize($file);
list($width_old, $height_old) = $info;

# Create image ressource
switch ( $info[2] ) {
    case IMAGETYPE_GIF:   $image = imagecreatefromgif($file);   break;
    case IMAGETYPE_JPEG:  $image = imagecreatefromjpeg($file);  break;
    case IMAGETYPE_PNG:   $image = imagecreatefrompng($file);   break;
    default: return false;
}

# We find the right ratio to resize the image before cropping
$heightRatio = $height_old / $height;
$widthRatio  = $width_old /  $width;

$optimalRatio = $widthRatio;
if ($heightRatio < $widthRatio) {
    $optimalRatio = $heightRatio;
}
$height_crop = ($height_old / $optimalRatio);
$width_crop  = ($width_old  / $optimalRatio);

# The two image ressources needed (image resized with the good aspect ratio, and the one with the exact good dimensions)
$image_crop = imagecreatetruecolor( $width_crop, $height_crop );
$image_resized = imagecreatetruecolor($width, $height);

# This is the resizing/resampling/transparency-preserving magic
if ( ($info[2] == IMAGETYPE_GIF) || ($info[2] == IMAGETYPE_PNG) ) {
    $transparency = imagecolortransparent($image);
    if ($transparency >= 0) {
        $transparent_color  = imagecolorsforindex($image, $trnprt_indx);
        $transparency       = imagecolorallocate($image_crop, $trnprt_color['red'], $trnprt_color['green'], $trnprt_color['blue']);
        imagefill($image_crop, 0, 0, $transparency);
        imagecolortransparent($image_crop, $transparency);
        imagefill($image_resized, 0, 0, $transparency);
        imagecolortransparent($image_resized, $transparency);
    }elseif ($info[2] == IMAGETYPE_PNG) {
        imagealphablending($image_crop, false);
        imagealphablending($image_resized, false);
        $color = imagecolorallocatealpha($image_crop, 0, 0, 0, 127);
        imagefill($image_crop, 0, 0, $color);
        imagesavealpha($image_crop, true);
        imagefill($image_resized, 0, 0, $color);
        imagesavealpha($image_resized, true);
    }
}

imagecopyresampled($image_crop, $image, 0, 0, 0, 0, $width_crop, $height_crop, $width_old, $height_old);
imagecopyresampled($image_resized, $image_crop, 0, 0, ($width_crop - $width) / 2, ($height_crop - $height) / 2, $width, $height, $width, $height);

# Writing image according to type to the output destination and image quality
switch ( $info[2] ) {
    case IMAGETYPE_GIF:   imagegif($image_resized, $output, 80);    break;
    case IMAGETYPE_JPEG:  imagejpeg($image_resized, $output, 80);   break;
    case IMAGETYPE_PNG:   imagepng($image_resized, $output, 9);    break;
    default: return false;
}

code de fichier work_edit.php

//ENVOIS DES IMAGES
    $work_id = $db->quote($_GET['id']);
    $files = $_FILES['images'];
    $images = array();
    include'../lib/image.php';
    foreach($files['tmp_name'] as $k => $v){
        $image = array(
            'name' => $files['name'][$k],
            'tmp_name' => $files['tmp_name'][$k]
        );
        $extension = pathinfo($image['name'], PATHINFO_EXTENSION);
        if(in_array($extension, array('jpg','png'))){
            $db->query("INSERT INTO images SET work_id=$work_id");
            $image_id = $db->lastInsertId();
            $image_name = $image_id . '.' . $extension;
            move_uploaded_file($image['tmp_name'], IMAGES . '/works/' . $image_name);
            resizeImage(IMAGES . '/works/' . $image_name, 150,150);
            $image_name = $db->quote($image_name);
            $db->query("UPDATE images SET name=$image_name WHERE id = $image_id");
        }
    }
    header('location:work.php');
    die();
}else{
setFlash('Le slug n\'est pas valide', 'danger');
}

}