<?php
$kaynak = file_get_contents('access.log');
preg_match_all("#images/(.*?)\.gif HTTP#i",$kaynak, $gif);

for($i=0; $i<count($gif[1]); $i++){
	$array[] = $gif[1][$i].'.gif';
}

echo '<pre>';
print_r(array_count_values($array)); 
echo '</pre>';
?>