ISO/IEC 13818-1:2019

INTERNATIONAL ISO/IEC
STANDARD 13818-1
Seventh edition
2019-06
Information technology — Generic
coding of moving pictures and
associated audio information —
Part 1:
Systems
Technologies de l'information — Codage générique des images
animées et du son associé —
Partie 1: Systèmes
Reference number
©
ISO/IEC 2019
© ISO/IEC 2019
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© ISO/IEC 2019 – All rights reserved

Foreword
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see www.iso.org/iso/foreword.html.
This document was prepared by ITU-T as Rec. ITU-T H.220.0 (03/2017) and drafted in accordance with
its editorial rules. It was assigned to Joint Technical Committee ISO/IEC JTC 1, Information
technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information.
This seventh edition cancels and replaces the sixth edition (ISO/IEC 13818-1:2018), which has
been technically revised. It also incorporates ISO/IEC 13818-1:2018/Amd.1:2018.
A list of all parts in the ISO/IEC 13818 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body.
A complete listing of these bodies can be found at www.iso.org/members.html.
© ISO/IEC 2019 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 13818-1
RECOMMENDATION ITU-T H.222.0
Information technology – Generic coding of moving pictures and associated
audio information: Systems
Summary
This Recommendation | International Standard specifies the system layer of the coding. It was developed in 1994 to
principally support the combination and synchronization of video and audio coding methods defined in ISO/IEC 13818
Part 2 (ITU-T H.262) and Part 3. Since 1994, this standard has been extended to support additional video coding
specifications (e.g., ISO/IEC 14496-2, ITU-T H.264 | ISO/IEC 14496-10, ITU-T H.265 | ISO/IEC 23008-2 and
ITU-T T.800 | ISO/IEC 15444-1 Annex M JPEG 2000 video), audio coding specifications (e.g., ISO/IEC 13818-7 and
ISO/IEC 14496-3), system streams (e.g., ISO/IEC 14496-1 and ISO/IEC 15938-1), ISO/IEC 23009-1 dynamic adaptive
streaming over HTTP (DASH), ISO/IEC 13818-11 intellectual property management and protection (IPMP) as well as
generic metadata. The system layer supports six basic functions:
1) the synchronization of multiple compressed streams on decoding;
2) the interleaving of multiple compressed streams into a single stream;
3) the initialization of buffering for decoding start up;
4) continuous buffer management;
5) time identification; and
6) multiplexing and signalling of various components in a system stream.
Recommendation ITU-T H.222.0 | ISO/IEC 13818-1 multiplexed bit stream is either a transport stream or a program
stream. Both streams are constructed from packetized elementary stream (PES) packets and packets containing other
necessary information. Both stream types support multiplexing of video and audio compressed streams from one program
with a common time base. The transport stream additionally supports the multiplexing of video and audio compressed
streams from multiple programs with independent time bases. For almost error-free environments the program stream is
generally more appropriate, supporting software processing of program information. The transport stream is more suitable
for use in environments where errors are likely.
Recommendation ITU-T H.222.0 | ISO/IEC 13818-1 multiplexed bit stream, whether a transport stream or a program
stream, is constructed in two layers: the outermost layer is the system layer, and the innermost is the compression layer.
The system layer provides the functions necessary for using one or more compressed data streams in a system. The video
and audio parts of this Specification define the compression coding layer for audio and video data. Coding of other types
of data is not defined by this Recommendation | International Standard, but is supported by the system layer provided that
the other types of data adhere to the constraints defined in this Recommendation | International Standard.
History
*
Edition Recommendation Approval Study Group Unique ID
1.0 ITU-T H.222.0 1995-07-10 15 11.1002/1000/1071
1.1 ITU-T H.222.0 (1995) Amd. 1 1996-11-11 16 11.1002/1000/3834
1.2 ITU-T H.222.0 (1995) Amd. 2 1996-11-11 16 11.1002/1000/4096
1.3 ITU-T H.222.0 (1995) Technical Cor. 1 1998-02-06 16 11.1002/1000/4532
1.4 ITU-T H.222.0 (1995) Amd. 3 1998-02-06 16 11.1002/1000/4228
1.5 ITU-T H.222.0 (1995) Amd. 4 1998-02-06 16 11.1002/1000/4229
1.6 ITU-T H.222.0 (1995) Amd. 5 1999-05-27 16 11.1002/1000/4498
1.7 ITU-T H.222.0 (1995) Amd. 6 1999-05-27 16 11.1002/1000/4671
2.0 ITU-T H.222.0 2000-02-17 16 11.1002/1000/5142
2.1 ITU-T H.222.0 (2000) Technical Cor. 1 2001-03-01 16 11.1002/1000/5419
2.2 ITU-T H.222.0 (2000) Technical Cor. 2 2002-03-29 16 11.1002/1000/5675
____________________
*
To access the Recommendation, type the URL http://handle.itu.int/ in the address field of your web browser, followed by the
Recommendation's unique ID. For example, http://handle.itu.int/11.1002/1000/11830-en.
© ISO/IEC 2019 – All rights reserved
Rec. ITU-T H.222.0 (08/2018) i

2.3 ITU-T H.222.0 (2000) Amd. 1 2002-12-14 16 11.1002/1000/6190
2.4 ITU-T H.222.0 (2000) Amd. 1/Cor. 1 2003-06-29 16 11.1002/1000/6449
2.5 ITU-T H.222.0 (2000) Amd. 2 2003-06-29 16 11.1002/1000/6363
2.6 ITU-T H.222.0 (2000) Amd. 3 2004-03-15 16 11.1002/1000/7208
2.7 ITU-T H.222.0 (2000) Technical Cor. 3 2005-01-08 16 11.1002/1000/7435
2.8 ITU-T H.222.0 (2000) Amd. 4 2005-01-08 16 11.1002/1000/7436
2.9 ITU-T H.222.0 (2000) Amd. 5 2005-01-08 16 11.1002/1000/7437
2.10 ITU-T H.222.0 (2000) Technical Cor. 4 2005-09-13 16 11.1002/1000/8560
3.0 ITU-T H.222.0 2006-05-29 16 11.1002/1000/8802
3.1 ITU-T H.222.0 (2006) Amd. 1 2007-01-13 16 11.1002/1000/9024
3.2 ITU-T H.222.0 (2006) Amd. 2 2007-08-29 16 11.1002/1000/9214
3.3 ITU-T H.222.0 (2006) Cor. 1 2008-06-13 16 11.1002/1000/9471
3.4 ITU-T H.222.0 (2006) Cor. 2 2009-03-16 16 11.1002/1000/9692
3.5 ITU-T H.222.0 (2006) Amd. 3 2009-03-16 16 11.1002/1000/9691
3.6 ITU-T H.222.0 (2006) Cor. 3 2009-12-14 16 11.1002/1000/10621
3.7 ITU-T H.222.0 (2006) Cor. 4 2009-12-14 16 11.1002/1000/10622
3.8 ITU-T H.222.0 (2006) Amd. 4 2009-12-14 16 11.1002/1000/10623
3.9 ITU-T H.222.0 (2006) Amd. 5 2011-05-14 16 11.1002/1000/11287
3.10 ITU-T H.222.0 (2006) Amd. 6 2011-05-14 16 11.1002/1000/11288
4.0 ITU-T H.222.0 2012-06-29 16 11.1002/1000/11655
4.1 ITU-T H.222.0 (2012) Amd. 1 2014-01-13 16 11.1002/1000/12054
4.2 ITU-T H.222.0 (2012) Amd. 2 2014-01-13 16 11.1002/1000/12055
4.3 ITU-T H.222.0 (2012) Amd. 3 2014-01-13 16 11.1002/1000/12056
4.4 ITU-T H.222.0 (2012) Amd. 4 2014-01-13 16 11.1002/1000/12057
4.5 ITU-T H.222.0 (2012) Amd. 5 2014-10-14 16 11.1002/1000/12306
5.0 ITU-T H.222.0 2014-10-14 16 11.1002/1000/12359
5.1 ITU-T H.222.0 (2014) Amd. 1 2015-04-29 16 11.1002/1000/12452
5.2 ITU-T H.222.0 (2014) Amd. 1 Cor. 1 2015-11-29 16 11.1002/1000/12625
5.3 ITU-T H.222.0 (2014) Amd. 2 2015-12-14 16 11.1002/1000/12632
5.4 ITU-T H.222.0 (2014) Amd. 3 2015-12-14 16 11.1002/1000/12633
5.5 ITU-T H.222.0 (2014) Amd. 1 Cor. 2 2016-07-14 16 11.1002/1000/12899
5.5 ITU-T H.222.0 (2014) Cor. 1 2016-07-14 16 11.1002/1000/12903
5.7 ITU-T H.222.0 (2014) Amd. 4 2016-07-14 16 11.1002/1000/12900
5.8 ITU-T H.222.0 (2014) Amd. 5 2016-07-14 16 11.1002/1000/12901
5.9 ITU-T H.222.0 (2014) Amd. 6 2016-07-14 16 11.1002/1000/12902
5.10 ITU-T H.222.0 (2014) Amd. 3 Cor. 1 2017-03-01 16 11.1002/1000/13184
5.10 ITU-T H.222.0 (2014) Cor. 2 2017-03-01 16 11.1002/1000/13188
5.12 ITU-T H.222.0 (2014) Amd. 7 2017-03-01 16 11.1002/1000/13186
5.13 ITU-T H.222.0 (2014) Amd. 8 2017-03-01 16 11.1002/1000/13187
6.0 ITU-T H.222.0 2017-03-01 16 11.1002/1000/13269
6.1 ITU-T H.222.0 (2017) Amd. 1 2017-12-14 16 11.1002/1000/13431
7.0 ITU-T H.222.0 2018-08-29 16 11.1002/1000/13664
Keywords
Audiovisual content, multimedia multiplexing, MPEG-2 system, multiplexed bit stream, program stream, transport stream.
© ISO/IEC 2019 – All rights reserved
ii Rec. ITU-T H.222.0 (08/2018)

FOREWORD
The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of
telecommunications, information and communication technologies (ICTs). The ITU Telecommunication
Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical,
operating and tariff questions and issuing Recommendations on them with a view to standardizing
telecommunications on a worldwide basis.
The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes
the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics.
The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1.
In some areas of information technology which fall within ITU-T's purview, the necessary standards are
prepared on a collaborative basis with ISO and IEC.
NOTE
In this Recommendation, the expression "Administration" is used for conciseness to indicate both a
telecommunication administration and a recognized operating agency.
Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain
mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the
Recommendation is achieved when all of these mandatory provisions are met. The words "shall" or some other
obligatory language such as "must" and the negative equivalents are used to express requirements. The use of
such words does not suggest that compliance with the Recommendation is required of any party.
INTELLECTUAL PROPERTY RIGHTS
ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve
the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or
applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of
the Recommendation development process.
As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected
by patents, which may be required to implement this Recommendation. However, implementers are cautioned
that this may not represent the latest information and are therefore strongly urged to consult the TSB patent
database at http://www.itu.int/ITU-T/ipr/.
 ITU 2019
All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior
written permission of ITU.
Rec. ITU-T H.222.0 (08/2018) iii
© ISO/IEC 2019 – All rights reserved

Table of Contents
Page
SECTION 1 – GENERAL . 1
1.1 Scope . 1
1.2 Normative references . 1
SECTION 2 – TECHNICAL ELEMENTS . 4
2.1 Definitions . 4
2.2 Symbols and abbreviations . 11
2.3 Method of describing bit stream syntax . 13
2.4 Transport stream bitstream requirements . 14
2.5 Program stream bitstream requirements . 60
2.6 Program and program element descriptors . 74
2.7 Restrictions on the multiplexed stream semantics . 143
2.8 Compatibility with ISO/IEC 11172 . 148
2.9 Registration of copyright identifiers . 148
2.10 Registration of private data format . 148
2.11 Carriage of ISO/IEC 14496 data . 149
2.12 Carriage of metadata . 160
2.13 Carriage of ISO 15938 data . 169
2.14 Carriage of Rec. ITU-T H.264 | ISO/IEC 14496-10 video . 169
2.15 Carriage of ISO/IEC 14496-17 text streams . 185
2.16 Carriage of auxiliary video streams . 187
2.17 Carriage of HEVC . 187
2.18 Carriage of green access units . 201
2.19 Carriage of ISO/IEC 23008-3 MPEG-H 3D audio data . 203
2.20 Carriage of Quality Access Units in MPEG-2 sections . 205
2.21 Carriage of Sample Variants . 206
2.22 Carriage of Media Orchestration Access Units . 207
Annex A – CRC decoder model . 208
A.1 CRC decoder model . 208
Annex B – Digital storage medium command and control (DSM-CC) . 209
B.1 Introduction . 209
B.2 General elements . 210
B.3 Technical elements . 212
Annex C – Program-specific information . 218
C.1 Explanation of program-specific information in transport streams . 218
C.2 Introduction . 218
C.3 Functional mechanism. 218
C.4 The mapping of sections into transport stream packets . 219
C.5 Repetition rates and random access . 219
C.6 What is a program? . 220
C.7 Allocation of program_number . 220
C.8 Usage of PSI in a typical system . 220
C.9 The relationships of PSI structures . 221
C.10 Bandwidth utilization and signal acquisition time . 223
Annex D – Systems timing model and application implications of this Recommendation | International Standard . 226
D.1 Introduction . 226
Annex E – Data transmission applications . 235
E.1 General considerations . 235
E.2 Suggestion . 235
Annex F – Graphics of syntax for this Recommendation | International Standard . 236
F.1 Introduction . 236
Annex G – General information . 240
G.1 General information . 240
iv Rec. ITU-T H.222.0 (08/2018)
© ISO/IEC 2019 – All rights reserved

Annex H – Private data . 241
H.1 Private data . 241
Annex I – Systems conformance and real-time interface . 242
I.1 Systems conformance and real-time interface . 242
Annex J – Interfacing jitter-inducing networks to MPEG-2 decoders . 243
J.1 Introduction . 243
J.2 Network compliance models . 243
J.3 Network specification for jitter smoothing. 244
J.4 Example decoder implementations . 245
Annex K – Splicing transport streams . 246
K.1 Introduction . 246
K.2 The different types of splicing point . 246
K.3 Decoder behaviour on splices. 247
Annex L – Registration procedure (see 2.9) . 249
L.1 Procedure for the request of a Registered Identifier (RID) . 249
L.2 Responsibilities of the Registration Authority . 249
L.3 Responsibilities of parties requesting an RID . 249
L.4 Appeal procedure for denied applications . 250
Annex M – Registration application form (see 2.9) . 251
M.1 Contact information of organization requesting a Registered Identifier (RID) . 251
M.2 Statement of an intention to apply the assigned RID . 251
M.3 Date of intended implementation of the RID . 251
M.4 Authorized representative . 251
M.5 For official use only of the Registration Authority . 251
Annex N – Registration Authority Diagram of administration structure (see 2.9) . 252
Annex O – Registration procedure (see 2.10) . 253
O.1 Procedure for the request of an RID . 253
O.2 Responsibilities of the Registration Authority . 253
O.3 Contact information for the Registration Authority . 253
O.4 Responsibilities of parties requesting an RID . 253
O.5 Appeal procedure for denied applications . 253
Annex P – Registration application form . 255
P.1 Contact information of organization requesting an RID . 255
P.2 Request for a specific RID . 255
P.3 Short description of RID that is in use and date system that was implemented . 255
P.4 Statement of an intention to apply the assigned RID . 255
P.5 Date of intended implementation of the RID . 255
P.6 Authorized representative . 255
P.7 For official use of the Registration Authority . 255
Annex Q – T-STD and P-STD buffer models for ISO/IEC 13818-7 ADTS . 256
Q.1 Introduction . 256
Q.2 Leak rate from transport buffer . 256
Q.3 Buffer size . 256
Q.4 Conclusion . 257
Annex R – Carriage of ISO/IEC 14496 scenes in Rec. ITU-T H.222.0 | ISO/IEC 13818-1. 259
R.1 Content access procedure for ISO/IEC 14496 program components within a program stream . 259
R.2 Content access procedure for ISO/IEC 14496 program components within a transport stream . 260
Annex S – Carriage of JPEG 2000 part 1 video over MPEG-2 transport streams . 264
S.1 Introduction . 264
S.2 J2K video access unit, J2K video elementary stream, J2K video sequence and J2K still picture . 264
S.3 Optional J2K block mode for high resolution support . 264
S.4 Optional J2K stripe mode for Ultra-Low Latency. 265
S.5 Elementary stream header (elsm) and mapping to PES packets . 265
Rec. ITU-T H.222.0 (08/2018) v
© ISO/IEC 2019 – All rights reserved

S.6 J2K transport constraints . 268
S.7 Interpretation of flags in adaptation and PES headers for J2K video elementary streams . 269
S.8 T-STD extension for J2K video elementary streams . 269
Annex T – MIME type for MPEG-2 transport streams . 272
T.1 Introduction . 272
T.2 MIME type and subtype . 272
T.3 Security considerations . 273
T.4 Parameters . 273
Annex U – Carriage of timeline and external media information over MPEG-2 transport streams . 275
U.1 Introduction . 275
U.2 TEMI access unit and TEMI elementary stream . 276
U.3 AF descriptors . 277
Annex V – Transport of HEVC tiles. 286
V.1 Introduction . 286
V.2 HEVC tile substream identification example . 286
V.3 Subregion layout example . 287

vi Rec. ITU-T H.222.0 (08/2018)
© ISO/IEC 2019 – All rights reserved

Introduction
The systems part of this Recommendation | International Standard addresses the combining of one or more elementary
streams of video and audio, as well as other data, into single or multiple streams which are suitable for storage or
transmission. Systems coding follows the syntactical and semantic rules imposed by this Specification and provides
information to enable synchronized decoding of decoder buffers over a wide range of retrieval or receipt conditions.
System coding shall be specified in two forms: the transport stream and the program stream. Each is optimized for a
different set of applications. Both the transport stream and program stream defined in this Recommendation | International
Standard provide coding syntax which is necessary and sufficient to synchronize the decoding and presentation of the
video and audio information, while ensuring that data buffers in the decoders do not overflow or underflow. Information
is coded in the syntax using time stamps concerning the decoding and presentation of coded audio and visual data and
time stamps concerning the delivery of the data stream itself. Both stream definitions are packet-oriented multiplexes.
The basic multiplexing approach for single video and audio elementary streams is illustrated in Figure Intro. 1. The video
and audio data is encoded as described in Rec. ITU-T H.262 | ISO/IEC 13818-2 and ISO/IEC 13818-3. The resulting
compressed elementary streams are packetized to produce PES packets. Information needed to use PES packets
independently of either transport streams or program streams may be added when PES packets are formed. This
information is not needed and need not be added when PES packets are further combined with system level information
to form transport streams or program streams. This systems standard covers those processes to the right of the vertical
dashed line.
Video data Video PES
Program
Video encoder Packetizer
stream
PS
Audio data Audio PES
Audio encoder Packetizer Mux
Transport
TS stream
Mux
Extent of systems specification
H.222.0(12)_F01
Figure Intro. 1 – Simplified overview of the scope of this Recommendation | International Standard
The program stream is analogous and similar to the ISO/IEC 11172 systems layer. It results from combining one or more
streams of PES packets, which have a common time base, into a single stream.
For applications that require the elementary streams that comprise a single program to be in separate streams that are not
multiplexed, the elementary streams can also be encoded as separate program streams, one per elementary stream, with a
common time base. In this case the values encoded in the SCR fields of the various streams shall be consistent.
Like the single program stream, all elementary streams can be decoded with synchronization.
The program stream is designed for use in relatively error-free environments and is suitable for applications which may
involve software processing of system information such as interactive multi-media applications. Program stream packets
may be of variable and relatively great length.
The transport stream combines one or more programs with one or more independent time bases into a single stream. PES
packets made up of elementary streams that form a program share a common timebase. The transport stream is designed
for use in environments where errors are likely, such as storage or transmission in lossy or noisy media. Transport stream
packets are 188 bytes in length.
Program and transport streams are designed for different applications and their definitions do not strictly follow a layered
model. It is possible and reasonable to convert from one to the other; however, one is not a subset or superset of the other.
In particular, extracting the contents of a program from a transport stream and creating a valid program stream is possible
and is accomplished through the common interchange format of PES packets, but not all of the fields needed in a program
stream are contained within the transport stream; some must be derived. The transport stream may be used to span a range
of layers in a layered model, and is designed for efficiency and ease of implementation in high bandwidth applications.
Rec. ITU-T H.222.0 (08/2018) vii
© ISO/IEC 2019 – All rights reserved

The scope of syntactical and semantic rules set forth in the systems specification differs: the syntactical rules apply to
systems layer coding only, and do not extend to the compression layer coding of the video and audio specifications; by
contrast, the semantic rules apply to the combined stream in its entirety.
The systems specification does not specify the architecture or implementation of encoders or decoders, nor those of
multiplexors or demultiplexors. However, bit stream properties do impose functional and performance requirements on
encoders, decoders, multiplexors and demultiplexors. For instance, encoders must meet minimum clock tolerance
requirements. Notwithstanding this and other requirements, a considerable degree of freedom exists in the design and
implementation of encoders, decoders, multiplexors, and demultiplexors.
Intro. 1 Transport stream
The transport stream is a stream definition which is tailored for communicating or storing one or more programs of coded
data according to Rec. ITU-T H.262 | ISO/IEC 13818-2 and ISO/IEC 13818-3 and other data in environments in which
significant errors may occur. Such errors may be manifested as bit value errors or loss of packets.
Transport streams may be either fixed or variable rate. In either case the constituent elementary streams may either be
fixed or variable rate. The syntax and semantic constraints on the stream are identical in each of these cases. The transport
stream rate is defined by the values and locations of program clock reference (PCR) fields, which in general are separate
PCR fields for each program.
There are some difficulties with constructing and delivering a transport stream containing multiple programs with
independent time bases such that the overall bit rate is variable. Refer to 2.4.2.3.
The transport stream may be constructed by any method that results in a valid stream. It is possible to construct transport
streams containing one or more programs from elementary coded data streams, from program streams, or from other
transport streams which may themselves contain one or more programs.
The transport stream is designed in such a way that several operations on a transport stream are possible with minimum
effort. Among these are:
1) Retrieve the coded data from one program within the transport stream, decode it and present the decoded
results as shown in Figure Intro. 2.
2) Extract the transport stream packets from one program within the transport stream and produce as output
a different transport stream with only that one program as shown in Figure Intro. 3.
3) Extract the transport stream packets of one or more programs from one or more transport streams and
produce as output a different transport stream (not illustrated).
4) Extract the contents of one program from the transport stream and produce as output a program stream
containing that one program as shown in Figure Intro. 4.
5) Take a program stream, convert it into a transport stream to carry it over a lossy environment, and then
recover a valid, and in certain cases, identical program stream.
Figure Intro. 2 and Figure Intro. 3 illustrate prototypical demultiplexing and decoding systems which take as input a
transport stream. Figure Intro. 2 illustrates the first case, where a transport stream is directly demultiplexed and decoded.
Transport streams are constructed in two layers:
– a system layer; and
– a compression layer.
The input stream to the transport stream decoder has a system layer wrapped about a compression layer. Input streams to
the video and audio decoders have only the compression layer.
Operations performed by the prototypical decoder which accepts transport streams either apply to the entire transport
stream ("multiplex-wide operations"), or to individual elementary streams ("stream-specific operations"). The transport
stream system layer is divided into two sub-layers, one for multiplex-wide operations (the transport stream packet layer),
and one for stream-specific operations (the PES packet layer).
A prototypical decoder for transport streams, including audio and video, is also depicted in Figure Intro. 2 to illustrate the
function of a decoder. The architecture is not unique – some system decoder functions, such as decoder timing control,
might equally well be distributed among elementary stream decoders and the channel-specific decoder – but this figure is
useful for discussion. Likewise, indication of errors detected by the channel-specific decoder to the individual audio and
video decoders may be performed in various ways and such communication paths are not shown in the diagram. The
prototypical decoder design does not imply any normative requirement for the design of a transport stream decoder.
Indeed non-audio/video data is also allowed, but not shown.
viii Rec. ITU-T H.222.0 (08/2018)
© ISO/IEC 2019 – All rights reserved

Decoded
video
Video decoder
Transport stream
Channel-specific
Channel
demultiplex and Clock control
decoder
decoder
Decoded
Transport stream audio
Audio decoder
containing one or multiple programs
H.222.0(12)_F02
Figure Intro. 2 – Prototypical transport demultiplexing and decoding example
Figure Intro. 3 illustrates the second case, where a transport stream containing multiple programs is converted into a
transport stream containing a single program. In this case the re-multiplexing operation may necessitate the correction of
program clock reference (PCR) values to account for changes in the PCR locations in the bit stream.
Transport stream
Channel-specific
Channel
demultiplex and
decoder
decoder
Transport stream
Transport stream
containing multiple programs
with single program
H.222.0(12)_F03
Figure Intro. 3 – Prototypical transport multiplexing example
Figure Intro. 4 illustrates a case in which a multi-program transport stream is first demultiplexed and then converted into
a program stream.
Figures Intro. 3 and Intro. 4 indicate that it is possible and reasonable to convert between different types and configurations
of transport streams. There are specific fields defined in the transport stream and program stream syntax which facilitate
the conversions illustrated. There is no requirement that specific implementations of demultiplexors or decoders include
all of these functions.
Transport stream
Channel Channel-specific
demultiplex and program
decoder
stream multiplexor
Transport stream
Program stream
containing multiple programs
H.222.0(12)_F04
Figure Intro. 4 – Prototypical transport stream to program stream conversion
Intro. 2 Program stream
The program stream is a stream definition which is tailored for communicating or storing one program of coded data and
other data in environments where errors are very unlikely, and where processing of system coding, e.g., by software, is a
major consideration.
Program streams may be either fixed or variable rate. In either case, the constituent elementary streams may be either
fixed or variable rate. The syntax and semantics constraints on the stream are identical in each case. The program stream
rate is defined by the values and locations of the system clock reference (SCR) and mux_rate fields.
A prototypical audio/video program stream decoder system is depicted in Figure Intro. 5. The architecture is not unique
– system decoder functions including decoder timing control might as equally well be distributed among elementary
stream decoders and the channel-specific decoder – but this figure is useful for discussion. The prototypical decoder
design does not imply any normative requirement for the design of a program stream decoder. Indeed non-audio/video
data is also allowed, but not shown.
Rec. ITU-T H.222.0 (08/2018) ix
© ISO/IEC 2019 – All rights reserved

Decoded
video
Video decoder
Channel Channel-specific Program stream
Clock control
decoder decoder
Decoded
audio
Audio decoder
Program
stream
H.222.0(12)_F05
Figure Intro. 5 – Prototypical decoder for program streams
The prototypical decoder for program streams shown in Figure Intro. 5 is composed of system
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