PHP CURL Problem with Pixhost.org

[heppinnz]

I am try upload image with this code:

$curl = curl_init();
        curl_setopt_array($curl, array(
            CURLOPT_URL => 'http://www.pixhost.org/cover-upload/',
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_CONNECTTIMEOUT => 30,
            CURLOPT_TIMEOUT => 30,
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => array(
                "0[]" => "@$file",
                'content_type' => '1',
                'tos' => 'on',
                'submit' => 'Upload'
        ));
        $return = curl_exec($curl);
        curl_close($curl); 

But everytime get one answer "Picture must be higher than 350px.".


Thank you for help!