jean@asuna:~/Projekte/Image/DuplicateFinder$ php test.php 
/home/jean/Projekte/Image/DuplicateFinder/test.php:36:
array(17) {
  '/home/jean/test/10/01/_.jpg' =>
  array(1) {
    [0] =>
    string(34) "/home/jean/test/10/01/100_0067.jpg"
  }
  '/home/jean/test/10/01/100_0065.jpg' =>
  array(2) {
    [0] =>
    string(34) "/home/jean/test/09/01/100_0065.jpg"
    [1] =>
    string(34) "/home/jean/test/08/01/100_0065.jpg"
  }
  '/home/jean/test/10/01/100_0068.jpg' =>
  array(2) {
    [0] =>
    string(34) "/home/jean/test/09/01/100_0068.jpg"
    [1] =>
    string(34) "/home/jean/test/08/01/100_0068.jpg"
  }
  '/home/jean/test/10/01/100_0067.jpg' =>
  array(2) {
    [0] =>
    string(34) "/home/jean/test/09/01/100_0067.jpg"
    [1] =>
    string(34) "/home/jean/test/08/01/100_0067.jpg"
  }
  '/home/jean/test/07/30/bild24.jpg' =>
  array(1) {
    [0] =>
    string(36) "/home/jean/test/07/30/f530019248.jpg"
  }


// ---- snip ----

foreach($files as $file)
 foreach ($this->finders as $finder) {
                        $finderName = $finder->getName();
                        $hash = $finder->getHash($file);
                        if (isset($this->hashes[$finderName][$hash])) {
                            $reference = $this->hashes[$finderName][$hash];
                            $this->duplicates[$reference][] = $file;
                            break;
                        }
                        $this->hashes[$finderName][$hash] = $file;
                    }