public function updateURL(&$url)
    {
        // Skip if resampling is off, or is already resampled, or is not an image
        if (!Config::inst()->get(get_class($this), 'force_resample') || $this->getVariant() || !$this->getIsImage()) {
            return;
        }

        // Attempt to resample
        $resampled = $this->Resampled();
        if (!$resampled) {
            return;
        }

        // Only update if resampled file is a smaller file size
        if ($resampled->getAbsoluteSize() < $this->getAbsoluteSize()) {
            $url = $resampled->getURL();
        }
    }