PHP code for remotely grabbing website images and saving them

Example, PHP code to capture website data.

/**
 * A class for grabbing images
 *
 * @package default
 * @author WuJunwei
*/
class download_image
{

 public $save_path; //The save address of the captured image

 //The size limit of the captured image (unit: Bytes) Only capture images larger than size than this limit
 public $img_size=0;

 //Define a static array to record the hyperlink addresses that have been crawled to avoid repeated crawling
 public static $ a_url_arr=array();

 /**
 * @param String $save_path The save address of the captured image
 * @param Int $img_size The save address of the captured image
*/
 public function __construct($save_path,$img_size)
 {
 $this->save_path=$save_path;
 $this->img_size=$img_size ;
 }

 /**
 * Method of recursively downloading and capturing images of the homepage and its subpages (recursive)
 *
 * @param String $capture_url URL used to capture images
 *
*/
 public function recursive_download_images($capture_url)
 {
 if (!in_array($capture_url,self::$a_url_arr)) //Not captured
 {
 self: :$a_url_arr[]=$capture_url; //Counted into static array
 } else //After capture, exit the function directly
 {
 return;
 }

 $this->download_current_page_images($capture_url); //Download All pictures on the current page

 //Use @ to block warning errors caused by the inability to read the capture address
 $content=@file_get_contents($capture_url);

 //Match the regular pattern before ? in the href attribute of the a tag
 $a_pattern = "|]+href=['" ]?([^ '"?]+)['" >]|U";
 preg_match_all($a_pattern, $content, $a_out, PREG_SET_ORDER);