I need someone with basic PHP to help with 1 line code

[spanakorizo]

for timthumb in my wordpress i use this code to

function first_image() {
  global $post, $posts;
  $first_img = '';
  ob_start();
  ob_end_clean();
  $output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches);
  $first_img = $matches [1] [0];

  if(empty($first_img)){ //Defines a default image
    $first_img = "images/default.gif";
  }
  return $first_img;
}

 

it works really well, then i thought why not to make it show random images if timthumb dont find any image?

 

so the 1st googling i did came up with this function:

<?php 
function getRandomFromArray($ar) { 
    mt_srand( (double)microtime() * 1000000 ); 
    $num = array_rand($ar); 
    return $ar[$num]; 
} 

function getImagesFromDir($path) { 
    $images = array(); 
    if ( $img_dir = @opendir($path) ) { 
        while ( false !== ($img_file = readdir($img_dir)) ) { 
            // checks for gif, jpg, png 
            if ( preg_match("/(\.gif|\.jpg|\.png)$/", $img_file) ) { 
                $images[] = $img_file; 
            } 
        } 
        closedir($img_dir); 
    } 
    return $images; 
} 

$root = ''; 
// If images not in sub directory of current directory specify root  
//$root = $_SERVER['DOCUMENT_ROOT']; 

$path = 'images/'; 

// Obtain list of images from directory  
$imgList = getImagesFromDir($root . $path); 

$img = getRandomFromArray($imgList); 

?>

 

and to show random image i Place the following where i wish the random image to appear:

 

<img src="<?php echo $path . $img ?>" alt="" />

 

my question is how to place this code in my function first_image??

i need to do something like this, but it doesnt make any sense:

if(empty($first_img)){ //Defines a default image

    $first_img = " <img src="<?php echo $path . $img ?>" alt="" />

this was my thought, if i can mix those 2 normally it should work, right?

 

or maybe there is another way to show random image in the

[i] if(empty($first_img)){ //Defines a default image[/i]
  [b]  $first_img =

?