How does blueimp jquery file upload write the upload path of the sample UploadHandeler.php to the laravel

https://blueimp.github.io/jQu.
Basic Plus Ui demo
I want to upload him to
public/pictures folder

how to change the example here?

UploadHandeler.php

public function _ _ construct ($options = null, $initialize = true,
$error_messages = null) {

    $this->response = array();
    $this->options = array(
        "script_url" => $this->get_full_url()."/".$this->basename($this->get_server_var("SCRIPT_NAME")),
        "upload_dir" => dirname($this->get_server_var("SCRIPT_FILENAME"))."/files/",
        "upload_url" => $this->get_full_url()."/files/",

what do you mean by "script_url"" here?

and I have changed it many times. I don"t know how to upload the picture to
public/pictures/

       "script_url" => $this->get_full_url()."/".$this->basename($this->get_server_var("SCRIPT_NAME")),
        "upload_dir" => dirname($this->get_server_var("SCRIPT_FILENAME"))."/pictures/",
        "upload_url" => $this->get_full_url()."/pictures/",

still no files will be uploaded successfully?
could you tell me how to write it here?