EN ISO/IEC 13818-1:1997

SLOVENSKI STANDARD
01-december-1997
Information technology - Generic coding of moving pictures and associated audio
information - Part 1: Systems (ISO/IEC 13818-1:1996)
Information technology - Generic coding of moving pictures and associated audio
information - Part 1: Systems (ISO/IEC 13818-1:1996)
Technologies de l'information - Codage générique des images animées et des
informations sonores associées - Partie 1: Systemes (ISO/IEC 13818-1:1996)
Ta slovenski standard je istoveten z: EN ISO/IEC 13818-1:1997
ICS:
35.040 Nabori znakov in kodiranje Character sets and
informacij information coding
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL lSO/IEC
STANDARD 13818-l
First edition
1996-04-I 5
Information technology - Generic coding
of moving pictures and associated audio
information: Systems
Technologies de /‘information - Codage des images animkes et du son
assock Sys t&mes
ISO/IEC 13818-1:1996(E)
CONTENTS
Page
Vi
Introduction .
vii
Intro. 1 Transport Stream .
ix
Intro. 2 Program Stream .
........................................................ X
Intro. 3 Conversion between Transport Stream and Program Stream
X
Intro. 4 Packetized Elementary Stream .
X
Intro. 5 Timing model .
xi
.........................................................................................................................
Intro. 6 Conditional access
xi
Multiplex-wide operations .
Intro. 7
Xi
.........................................................................
Intro. 8 Individual stream operations (PES Packet Layer)
xi
Intro. 8.1 Demultiplexing .
xii
Intro. 8.2 Synchronization .
xii
Relation to compression layer .
Intro. 8.3
xii
System reference decoder .
Intro. 9
xii
Intro. 10 Applications .
SECTION 1 - GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~.~.*.
1.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~.
1.2 Normative references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Identical Recommendations I International Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Additional references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 2 - TECHNICAL ELEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Symbols and abbreviations .
2.2.1 Arithmetic operators .
..............................................................................................................
2.2.2 Logical operators
..........................................................................................................
2.2.3 Relational operators
2.2.4 Bitwise operators .
2.2.5 Assignment .
2.2.6 Mnemonics .
2.2.7 Constants .
.............................................................................................. 7
2.3 Method of describing bit stream syntax
2.4 Transport Stream bitstream requirements .
2.4.1 Transport Stream coding structure and parameters . 8
2.4.2 Transport Stream system target decoder .
............................................ 17
2.4.3 Specification of the Transport Stream syntax and semantics
........................................................................ 18
2.4.3.2 Transport Stream packet layer
2.4.3.3 Semantic definition of fields in Transport Stream packet layer . 18
2.4.3.4 Adaptation field .
2.4.3.5 Semantic definition of fields in adaptation field .
2.4.3.6 PES packet .
0 ISO/IEC 1996
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0 ISO/IEC
ISO/IEC 13818=1:1996(E)
....................................................
Semantic definition of fields in PES packet
2.4.3.7
Carriage of Program Streams and ISO/IEC 11172-l Systems streams in the
2.4.3.8
Transport Stream .
............................................................................................ 39
Program specific information
2.4.4
2.4.4.1 Pointer .
..............................................
2.4.4.2 Semantics definition of fields in pointer syntax
.............................................................................. 41
2.4.4.3 Program association Table
2.4.4.4 Table id assignments .
......................... 42
2.4.4.5 Semantic - . definition of fields in program association section
2.4.4.6 Conditional access Table .
2.4.4.7 .
Semantic definition of fields in conditional access section
........................................................................................ 44
2.4.4.8 Program Map Table
........ 44
2.4.4.9 Semantic definition of fields in Transport Stream program map section
...........................................................................
2.4.4.10 Syntax of the Private section
............................................... 46
2.4.4.11 Semantic definition of fields in private section
Program Stream bitstream requirements .
2.5
............................................................ 47
2.5.1 Program Stream coding structure and parameters
............................................................................. 47
2.5.2 Program Stream system target decoder
2.5.2.1 System clock frequency .
....................................... 49
2.5.2.2 Input to the Program Stream system target decoder
2.5.2.3 Buffering .
2.5.2.4 PES streams .
.............................................................................. 5%
2.5.2.5 Decoding and presentation
............................................. 51
2.5.3 Specification of the Program Stream syntax and semantics
2.5.3.1 Program Stream .
Semantic definition of fields in Program Stream .
2.5.3.2
2.5.3.3 Pack layer of Program Stream .
.................................... 52
2.5.3.4 Semantic definition of fields in program stream pack
System header .
2.5.3.5
............................................... 53
2.5.3.6 Semantic definition of fields in system header
2.5.3.7 Packet layer of Program Stream .
2.5.4 Program Stream map .
...................................................................... 55
2.5.4.1 Syntax of Program Stream map
.................................... 56
2.5.4.2 Semantic definition of fields in Program Stream map
Program Stream directory .
2.5.5
Syntax of Program Stream directory packet . 57
2.5.5.1
............................. 57
2.5.5.2 Semantic definition of fields in Program Stream directory
......................................................................................... 59
2.6 Program and program element descriptors
..................... 59
2.6.1 Semantic definition of fields in program and program element descriptors
....................................................................................................
2.6.2 Video stream descriptor
................................................. 60
2.6.3 Semantic definitions of fields in video stream descriptor
2.6.4 Audio stream descriptor .
Semantic definition of fields in audio stream descriptor .
2.6.5
.......................................................................................................... 61
2.6.6 Hierarchy descriptor
........................................................ 62
2.6.7 Semantic definition of fields in hierarchy descriptor
2.6.8 Registration descriptor .
Semantic definition of fields in registration descriptor . 63
2.6.9
...................................................................................... 63
2.6.10 Data stream alignment descriptor
2.6.11 Semantics of fields in data stream alignment descriptor .
64 *
....................................................................................
2.6.12 Target background grid descriptor
.................................................. 64
2.6.13 Semantics of fields in target background grid descriptor
2.6.14 Video window descriptor .
................................................
2.6.15 Semantic definition of fields in video window descriptor
2.6.16 Conditional access descriptor .
.......................................... 66
2.6.17 Semantic definition of fields in conditional access descriptor
IS0 639 language descriptor .
2.6.18
.......................................... 66
2.6.19 Semantic definition of fields in IS0 639 language descriptor
. . .
0 ISO/IEC
ISO/IEC 13818=1:1996(E)
2.6.20 System clock descriptor .
.................................................. 67
2.6.2 1 Semantic definition of fields in system clock descriptor
Multiplex buffer utilization descriptor .
2.6.22
............................ 67
2.6.23
Semantic definition of fields in multiplex buffer utilization descriptor
2.6.24 Copyright descriptor .
........................................................ 68
2.6.25 Semantic definition of fields in copyright descriptor
2.6.26 .
Maximum bitrate descriptor
............................................
2.6.27 Semantic definition of fields in maximum bitrate descriptor
2.6.28 Private data indicator descriptor .
..................................... 69
2.6.29 Semantic definition of fields in Private data indicator descriptor
2.6.30 Smoothing buffer descriptor .
...........................................
2.6.3 1 Semantic definition of fields in smoothing buffer descriptor
2.6.32 STD descriptor .
Semantic definition of fields in STD descriptor .
2.6.33
2.6.34 IBP descriptor .
.................................................................
2.6.35 Semantic definition of fields in IBP descriptor
..............................................................................
2.7 Restrictions on the multiplexed stream semantics
..............................................................
2.7.1 Frequency of coding the system clock reference
............................................................
2.7.2 Frequency of coding the program clock reference
............................................ 71
2.7.3 Frequency of coding the elementary stream clock reference
...................................................................
2.7.4 Frequency of presentation timestamp coding
....................................................................................
2.7.5 Conditional coding of timestamps
.............................................................................
2.7.6 Timing constraints for scalable coding
..................................... 72
2.7.7 Frequency of coding P-STD - buffer - size in PES packet headers
2.7.8 Coding of system header in the Program Stream .
...............................................................
2.7.9 Constrained system parameter Program Stream
...............................................................................................................
2.7.10 Transport Stream
2.8 Compatibility with ISO/IEC 11172 .
Annex A
- CRC Decoder Model .
A.0 CRC decoder model .
................................................................
Annex B - Digital Storage Medium Command and Control (DSM-CC)
.........................................................................................................................................
B.0 Introduction
Purpose .
B.O.l
............................................................................................................
B.0.2 Future applications
............................................................................................................................
B.0.3 Benefits
..................................................................................................................
B.0.4 Basic functions
Stream selection .
B.0.4.1
..........................................................................................................
B.0.4.2 Retrieval
............................................................................................................
B.0.4.3 Storage
.................................................................................................................................
B. 1 General elements
Scope .
B.l.l
..............................................................................
B.1.2 Overview of the DSM-CC application
....................................
B.1.3 The transmission of DSM-CC commands and acknowledgments
Technical elements .
B .2
.........................................................................................................................
B.2.1 Definitions
.....................................................................................
B.2.2 Specification of DSM-CC syntax
...................................................
Semantics of fields in specification of DSM-CC syntax
B.2.3
Control layer .
B.2.4
...................................................................................
B.2.5 Semantics of fields in control layer
.....................................................................................................
B.2.6 Acknowledgment layer
...................................................................
B.2.7 Semantics of fields in acknowledgment layer
..........................................................................................................................
B.2.8 Time code
.......................................................................................
Semantics of fields in time code
B.2.9
...............................................................................................................
Annex C - Program Specific Information
.................................................. 85
C.0 Explanation of Program Specific Information in Transport Streams
C. 1 Introduction .
........................................................................................................................
C.2 Functional Mechanism
iv
0 ISO/IEC
ISO/IEC 13818=1:1996(E)
C.3 The Mapping of Sections into Transport Stream Packets
................................................................... 86
C.4 Repetition Rates and Random Access . 86
C.5 What is a Program? . 86
C.6 Allocation of program number .
-
C.7 Usage of PSI in a Typical System . 87
C.8 The Relationships of PSI Structures . 88
C.8.1 Program Association Table . 88
C.8.2 Program Map Table . 88
C.8.3 Conditional Access Table . 88
C.8.4 Network Information Table . 90
C.8.5 Private-section0 . 90
........................................................................................................................ 90
C.8.6 Descriptors
C.9 Bandwidth Utilization and Signal Acquisition Time . 90
Annex D - Systems Timing Model and Application Implications of this Recommendation 1 International
Standard . 93
D.0 Introduction . 93
D.O. 1 Timing Model . 93
D.0.2 Audio and Video Presentation Synchronization . 94
D.0.3 System Time Clock recovery in the decoder . 96
D.0.4 SCR and PCR Jitter . 98
D.0.5 Clock Recovery in the Presence of Network Jitter . 99
D.0.6 System clock used for chroma sub-carrier generation . 100
D.0.7 Component video and audio reconstruction . BOB
D.0.8 Frame Slipping . 101
D.0.9 Smoothing of network jitter . 101
Annex E - Data Transmission Applications . 103
E.0 General considerations . 103
E.l Suggestion
........................................................................................................................................... 103
Annex F - Graphics of Syntax for this Recommendation I International Standard
................................................ 104
F.0 Introduction . 104
F.O. 1
Transport Stream syntax . 104
F.0.2 .
PES packet 105
F.0.3 Program Association Section . 106
F.0.4 CA section . 106
F.0.5 TS program map section . 107
F.0.6 Private section . 107
F.0.7
Program Stream . 108
F.0.8 Program Stream map .
Annex G - General Information .
G.0 General Information . 110
G.O. 1 Sync Byte Emulation . 110
G.0.2 .
Skipped picture status and decoding process 110
G.0.3 .
Selection of PID Values 110
G.0.4 PES start code emulation . 110
-
Annex H - Private Data
........................................................................................................................................... 111
H.0 Private Data . 111
Annex I - Systems conformance and real-time interface . 112
1.0 Systems conformance and real-time interface . 112
Annex J - Interfacing Jitter-Inducing Networks to MPEG-2 Decoders
................................................................. 113
J.0 Introduction
......................................................................................................................................... 113
J.l Network compliance models . 113
5.2 Network specification for jitter smoothing
......................................................................................... 114
5.3 Example decoder implementations . 115
5.3.1 Network adapter followed by an MPEG-2 decoder . 115
5.3.2 .
Integrated decoder 115
V
ISO/IEC 13818=1:1996(E) 0 ISOIIEC
Annex K - Splicing Transport Streams .
K.0 Introduction . 117
K. 1 The different types of splicing point . 117
K.l.1 Ordinary splicing points . 117
K.1.2 Seamless splicing points .
K.2 Decoder behaviour on splices . 118
K.2.1 On non-seamless splices . 118
K.2.2 On seamless splices . 118
Buffer Overflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
K.2.3 118
vi
@ ISO/IEC ISO/IEC 13818=1:1996(E)
Foreword
IS0 (the International Organization for Standardization) and IEC (the
International Electrotechnical Commission) form the specialized system for
worldwide standardization. National bodies that are members of IS0 or IEC par-
ticipate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields
of technical activity. IS0 and IEC technical committees collaborate in fields of
mutual interest. Other international organizations, governmental and non-
governmental, in liaison with IS0 and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint
technical committee, ISO/IEC JTC 1. 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.
International Standard ISO/IEC 138 18- 1 was prepared by Joint Technical
Committee ISO/IEC JTC 1, Information technology, in collaboration with ITU-T.
The identical text is published as ITU-T Recommendation H.222.0.
ISOIIEC 138 18 consists of the following parts, under the general title Information
technology - Generic coding of moving pictures and associated audio
information:
- Part I: Systems
- Part 2: Video
- Part 3: Audio
Part 4: Compliance testing
- Part 6: Extensions for DSM-CC
- Part 9: Extension for real time inter$ace for systems decoders
Annex A forms an integral part of this part of ISO/IEC 138 18. Annexes B to K are
for information only.
ISO/IEC 138184:1996(E) 0 ISO/IEC
Introduction
The systems part of this Recommendation I 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 I
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 ITU-T Rec. H.262 1 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
A
right of the vertical dashed line.
:
:
:
:
:
:
.
Video PES
:
Video Video
Packetizer b
data encoder
:
:
PS
:
:
Program
:
:
:
Stream ’
I
’ : ’
.
: mux
: Audio PES
Audio Audio
Packetizer b
data encoder
:
:
:
:
TS
Transport
Stream ’
Extent of systems specification
Figure Intro. 1 - Simplified overview the scope of this Recommendation I International Standard
The Program Stream is analogous and similar to ISOLIEC 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 which comprise a single program to be in separate streams which
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.
. . .
Vlll
0 ISO/IEC
ISO/IEC 13818=1:1996(E)
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.
The scope of syntactical and semantic rules set forth in the systems specification differ: 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 ITU-T Rec. H.262 I ISO/IEC 138 18-2 and ISO/IEC 138 18-3 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 2.4.2.2.
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.
Extract the Transport Stream packets of one or more programs from one or more Transport Streams and
3)
produce as output a di fferent Transport Stream (not ill ustrated).
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.
Take a Program Stream, convert it into a Transport Stream to and then
carry it over a lossy environment,
5)
recover a valid, and in certain cases, identical Program Stream

ISO/IEC 13818=1:1996(E) 0 ISO/IEC
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.
Video Decoded
b
decoder video
Transport Stream
Channel
Channel specific Clock
b
demultiplex
decoder cant rol
4L b
and decoder
I
t
\i
Transport Stream ’ Audio Decoded
L
containing one or multiple programs decoder audio
TlSO5770-95’dO2
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
Channel specific
I
b b
demultiplex
decoder
and decode
! :
TISO5780-95/dO3
i
’ i
Transport SW&n Transport Stream
with single program
containing multiple programs
Figure Intro. 3 - Prototypical transport multiplexing example

0 ISO/IEC
ISO/IEC 13818-l: 1996(E)
Figure Intro. 4 illustrates a case in which an 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
...