protected function applyFilters()
  {
    if ($this->emptyRessource) {
      $source = $this->emptyRessource;
    } else if ($this->extension == self::IMAGE_TYPE_JPG) {
      $source = imagecreatefromjpeg($this->path);
    } else if ($this->extension == self::IMAGE_TYPE_PNG) {
      $source = imagecreatefrompng($this->path);
      imagealphablending($source, false);
      imagesavealpha($source, true);
    }
    foreach($this->filters as $filtre) {
      $source = $filtre->apply($source);
    }
    $this->buildedRessource = $source;
    return $source;
  }