* @param file the file path
         * @return the extracted document ID
         */
        protected String getDocId(final Path file) {
            final String s = file.toUri().toString();
            final String b = basePath.toUri().toString();
            final String id = s.replace(b, StringUtil.EMPTY).replace("." + imageExtention, StringUtil.EMPTY).replace("/", StringUtil.EMPTY);
            if (logger.isDebugEnabled()) {