private function setPrefixes()
    {
        $pathArray = array($this->optionsProvider->getVarDir());

        // The storage dir itself might be null
        if ($storageDir = $this->optionsProvider->getStorageDir()) {
            $pathArray[] = $storageDir;
        }

        $this->draftPrefix = implode('/', array_merge($pathArray, array($this->optionsProvider->getDraftImagesDir())));
        $this->publishedPrefix = implode('/', array_merge($pathArray, array($this->optionsProvider->getPublishedImagesDir())));
    }