View difference between Paste ID: 56X9mX9R and ExMqiRJv

 <?php
 add_action( 'after_setup_theme', 'dr_post_theme_setup' );
 if ( !function_exists( 'dr_post_theme_setup' ) ):
 function dr_post_theme_setup() {
 
 	/* Remove the twenty eleven default Headers */
 	function dr_update_twenty_eleven_headers(){
 		unregister_default_headers( array(
 			'wheel',
 			'shore',
 			'trolley',
 			'pine-cone',
 			'chessboard',
 			'lanterns',
 			'willow' ,
 			'hanoi')
 			);
 
 		// Register default custom headers packaged with the child theme.
 		$headers = dr_default_headers();
 		if( $headers ) register_default_headers( $headers );
 	}
 	add_action( 'after_setup_theme', 'dr_update_twenty_eleven_headers', 11 );
 }
 endif;
 
 // read through the /images/headers/ to get a list of custom headers.
 function dr_default_headers(){
 	// Create an empty array
     $list = array();
 	// Get the file directory path and url
 	$path = get_stylesheet_directory() .'/images/headers/';
 	$url = get_stylesheet_directory_uri() .'/images/headers/';
     // Open the /images/headers/ folder
     $dir_handle = @opendir($path) or die("Unable to open $path");
 	// Loop through the header images
     while($file = readdir($dir_handle)){
         if($file == "." || $file == ".."){continue;}
         $filename = explode(".",$file);
         $cnt = count($filename); $cnt--; $ext = $filename[$cnt];
         // Is the image a jpg or png
         if(strtolower($ext) == ('png' || 'jpg')){
 			// if the image is post fixed with -thumbnail add it to the array
 			if ( strpos($file, '-thumbnail') > 0 ) {
 				$name = substr($file, 0, strpos($file, '-thumbnail') );
 				$list[$name] = array(
 					'url' => $url .$name .'.' .$ext,
 					'thumbnail_url' => $url .$file,
 					'description' => __( ucwords( str_replace("-"," ",$name) ), 'twentyeleven' )
 				);
 			}
 		}
     }
     return $list;
 }