RTP Payload Format for the 1998 Version of ITU-T Rec. H.263 Video (H.263+)
RFC 2429

Document Type RFC - Proposed Standard (October 1998; No errata)
Obsoleted by RFC 4629
Last updated 2013-03-02
Stream IETF
Formats plain text pdf htmlized bibtex
Stream WG state (None)
Document shepherd No shepherd assigned
IESG IESG state RFC 2429 (Proposed Standard)
Consensus Boilerplate Unknown
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group
Request for Comments: 2429                                    C. Bormann
Category: Standards Track                                   Univ. Bremen
                                                                L. Cline
                                                              G. Deisher
                                                               T. Gardos
                                                             C. Maciocco
                                                               D. Newell
                                                                   Intel
                                                                  J. Ott
                                                            Univ. Bremen
                                                             G. Sullivan
                                                              PictureTel
                                                               S. Wenger
                                                               TU Berlin
                                                                  C. Zhu
                                                                   Intel
                                                            October 1998

               RTP Payload Format for the 1998 Version of
                    ITU-T Rec. H.263 Video (H.263+)

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1998).  All Rights Reserved.

1. Introduction

   This document specifies an RTP payload header format applicable to
   the transmission of video streams generated based on the 1998 version
   of ITU-T Recommendation H.263 [4].  Because the 1998 version of H.263
   is a superset of the 1996 syntax, this format can also be used with
   the 1996 version of H.263 [3], and is recommended for this use by new
   implementations.  This format does not replace RFC 2190, which
   continues to be used by existing implementations, and may be required
   for backward compatibility in new implementations.  Implementations
   using the new features of the 1998 version of H.263 shall use the
   format described in this document.

Bormann, et. al.            Standards Track                     [Page 1]
RFC 2429                         H.263+                     October 1998

   The 1998 version of ITU-T Recommendation H.263 added numerous coding
   options to improve codec performance over the 1996 version.  The 1998
   version is referred to as H.263+ in this document.  Among the new
   options, the ones with the biggest impact on the RTP payload
   specification and the error resilience of the video content are the
   slice structured mode, the independent segment decoding mode, the
   reference picture selection mode, and the scalability mode.  This
   section summarizes the impact of these new coding options on
   packetization.  Refer to [4] for more information on coding options.

   The slice structured mode was added to H.263+ for three purposes: to
   provide enhanced error resilience capability, to make the bitstream
   more amenable to use with an underlying packet transport such as RTP,
   and to minimize video delay.  The slice structured mode supports
   fragmentation at macroblock boundaries.

   With the independent segment decoding (ISD) option, a video picture
   frame is broken into segments and encoded in such a way that each
   segment is independently decodable.  Utilizing ISD in a lossy network
   environment helps to prevent the propagation of errors from one
   segment of the picture to others.

   The reference picture selection mode allows the use of an older
   reference picture rather than the one immediately preceding the
   current picture.  Usually, the last transmitted frame is implicitly
   used as the reference picture for inter-frame prediction.  If the
   reference picture selection mode is used, the data stream carries
   information on what reference frame should be used, indicated by the
   temporal reference as an ID for that reference frame.  The reference
   picture selection mode can be used with or without a back channel,
   which provides information to the encoder about the internal status
   of the decoder.  However, no special provision is made herein for
   carrying back channel information.

   H.263+ also includes bitstream scalability as an optional coding
   mode.  Three kinds of scalability are defined: temporal, signal-to-
   noise ratio (SNR), and spatial scalability.  Temporal scalability is
   achieved via the disposable nature of bi-directionally predicted
   frames, or B-frames. (A low-delay form of temporal scalability known
Show full document text