无法通过 cURL 发送图像

由于某种原因，我无法通过cURL将图像发送到外部服务器。可能是一些小东西，但我已经看了几个小时的这段代码了，但仍然不知道出了什么问题......

$ch = curl_init();
$data = array(
    'fbid' => $userProfile['id'],
    'name' => $userProfile['name'],
    'email' => $userProfile['email'],
    'gender' => $userProfile['gender'],
    'title' => $_POST['title'],
    'original' => '@' . UPLOAD_PATH . $imageFilename,
    'thumbnail' => '@' . UPLOAD_PATH . $thumbnailFilename,
    'cropped' => '@' . UPLOAD_PATH . $croppedImageFilename
);
curl_setopt($ch, CURLOPT_URL, 'http://www.domain.com/curl.php');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_BINARYTRANSFER,1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_exec($ch);

文本正在通过，如果我在远程服务器上打印出 _POST 美元，这就是我得到的......

Array (
    [fbid] => 12345
    [name] => My Name
    [email] => email@domain.com
    [gender] => male
    [title] => Image title
)

任何帮助将不胜感激:P