code: public void extract(@NotNull final byte[] xmpBytes, @NotNull Metadata metadata, @Nullable Directory parentDirectory)
      {
          extract(xmpBytes, 0, xmpBytes.length, metadata, parentDirectory);
      }
docs: Performs the XMP data extraction, adding found values to the specified instance of {@link Metadata}.
  <p>
  The extraction is done with Adobe's XMPCore library.