fix issues with the banner script not working

PHP 7.4
Notice: Trying to access array offset on value of type resource in on line 13

Notice: Trying to access array offset on value of type resource in on line 14

Notice: fpassthru(): read of 8192 bytes failed with errno=21 Is a directory in  on line 17

b.php

@@ -10,8 +10,9 @@ $fp = fopen($dir . $name, 'rb');
 header('Cache-Control: no-cache, no-store, must-revalidate'); // HTTP 1.1
 header('Pragma: no-cache'); // HTTP 1.0
 header('Expires: 0'); // Proxies
-header('Content-Type: ' . $fp['type']);
-header('Content-Length: ' . $fp['bytes']);
+$fstat = fstat($fp);
+header('Content-Type: ' . mime_content_type($dir . $name));
+header('Content-Length: ' . $fstat['size']);
 
 // dump the picture and stop the script
 fpassthru($fp);