This streambuf decodes all hexBinary-encoded data read from the istream connected to it. In hexBinary encoding, each binary octet is encoded as a character tuple, consisting of two hexadecimal digits ([0-9a-fA-F]) representing the octet code. See also: XML Schema Part 2: Datatypes (http://www.w3.org/TR/xmlschema-2/), section 3.2.15.

Note: For performance reasons, the characters are read directly from the given istream's underlying streambuf, so the state of the istream will not reflect that of its streambuf.