private PsdImageContents readImageContents(final ByteSource byteSource) throws ImagingException, IOException {
        try (InputStream is = byteSource.getInputStream()) {
            return readImageContents(is);
        }
    }
Extracts embedded XML metadata as XML string.

@param byteSource File containing image data.
@param params     Map of optional parameters, defined in ImagingConstants.
@return Xmp Xml as String, if present. Otherwise, returns null.
src/main/java/org/apache/commons/imaging/formats/psd/PsdImageParser.java