ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with padicular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights
Amendment3 to ISO/IEC21000-5:2004 was prepared by Joint Technical Committee ISO/IECJTCf,
information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia
information.