code: def _parse_unrecognized_segment(self, fptr):
          
          msg = ("Unrecognized codestream marker 0x{marker_id:x} encountered at "
                 "byte offset {offset}.")
          msg = msg.format(marker_id=self._marker_id, offset=fptr.tell())
          warnings.warn(msg, UserWarning)
          cpos = fptr.tell()
          read_buffer = fptr.read(2)
          next_item, = struct.unpack('>H', read_buffer)
          fptr.seek(cpos)
          if ((next_item & 0xff00) >> 8) == 255:
                  # No segment associated with this marker, so reset
                  # to two bytes after it.
              segment = Segment(id='0x{0:x}'.format(self._marker_id),
                                offset=self._offset, length=0)
          else:
              segment = self._parse_reserved_segment(fptr)
          return segment
docs: Looks like a valid marker, but not sure from reading the specs.