把上传图片文件转换格式

function getImageHander ($url) {
    $size=@getimagesize($url);
    switch($size['mime']){
        case 'image/jpg': $im = imagecreatefromjpeg($url);break;
        case 'image/jpeg': $im = imagecreatefromjpeg($url);break;
        case 'image/gif' : $im = imagecreatefromgif($url);break;
        case 'image/png' : $im = imagecreatefrompng($url);break;
        default: $im=false;break;
    }
    return $im;
}

    $image = getImageHander($_FILES[$upload_name]["tmp_name"]);
    $file="./upload/icon/$hr_id.jpg";
    imagejpeg($image,$file);
    imagedestroy($image);