SIST-TP ETR 154 E2:2005
(Main)Digital Video Broadcasting (DVB); DVB implementation guidelines for the use of MPEG-2 Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications
- Abstract
Update of ETR 154 Edition 1 in order to cope with: - changes in MPEG 2 Systems transport stream in view of Recorder applications; - terrestrial broadcasting applications.
- Status
- Published
- Publication Date
- 31-Oct-2005
- Technical Committee
- RES - Radio equipment and systems
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 01-Nov-2005
- Due Date
- 01-Nov-2005
- Completion Date
- 01-Nov-2005
- Mandate
- T-304
SIST-TP ETR 154 E2:2005 is a SIST technical prestandard that presents Digital Video Broadcasting (DVB) implementation guidelines for using MPEG-2 Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications. It specifies baseline behavior for Integrated Receiver-Decoders (IRD) and encoder constraints so broadcast services and receiver implementations can interoperate.
What does SIST-TP ETR 154 E2:2005 specify?
SIST-TP ETR 154 E2:2005 gives practical DVB guidance for MPEG-2 audio-visual coding in conventional-resolution digital television, plus guidance for devices with a digital interface used for digital VCR applications. The scope is focused on broadcast delivery and recorder-related transport streams, not on interactive services or HDTV.
The document is organized into:
- clause 1, scope
- clause 2, references
- clause 3, definitions, symbols and abbreviations
- clause 4, systems layer
- clause 5, video
- clause 6, audio
Clause 4 covers broadcast bit-streams, Baseline IRDs, storage media interoperability, Partial Transport Streams and trick play data. Clauses 5 and 6 set the video and audio constraints that encoders should follow and IRDs should decode.
What are the key requirements of SIST-TP ETR 154 E2:2005?
SIST-TP ETR 154 E2:2005 defines a baseline DVB profile for transport, video and audio so that receivers can decode common services correctly. In practice, the document tells broadcasters what to send and receiver makers what they must handle.
Systems layer
Clause 4 requires the transmitted multiplex to use the MPEG-2 Transport Stream (TS), and Baseline IRDs shall demultiplex TS. Program streams are optional for decoding. This matters because the main DVB carriage model is TS, so headends and receivers must be built around that structure.
Clause 4.1.4 and 4.1.5 set the key packet and timing behavior. Scrambling control follows ETR 289, Program Clock Reference (PCR) spacing shall not exceed 100 milliseconds and 40 milliseconds is recommended, and fields such as null packets, adaptation field data and other optional fields must be handled according to their flags. In practice, this keeps timing stable enough for decoder synchronization and makes sure reserved or optional fields do not break reception.
Clause 4.1.7 and 4.1.8 focus on Program Specific Information (PSI), Service Information (SI) and descriptors. The Program Association Table (PAT) and Program Map Table (PMT) are recommended to repeat at intervals of up to 100 milliseconds, the CA_descriptor follows ETR 289, and the ISO_639_Language_descriptor is required when a program carries multiple languages. This is what lets receivers find services, select the right language and interpret conditional access and service metadata.
Clause 4.2 addresses storage and digital interface use. Partial Transport Streams are defined for digital interface transfer and must remain MPEG compliant with ISO/IEC IS 13818-9, while decoders for digital VCR applications shall accept the bursty behavior and gaps of a Partial Transport Stream. The trick mode section allows recorder playback data to use DSM_trick_mode signaling and defines semantic exceptions during trick play. This matters for recorder interoperability, where playback is not a continuous broadcast stream.
Video
Clause 5 requires MPEG-2 Main Profile at Main Level for encoded bit-streams, with a 25 Hz frame rate. The receiver side shall support Main Profile syntax and still pictures. This keeps the service within a widely supported DVB video profile and makes pause or still-frame use practical.
Clause 5.3 limits the source aspect ratio to 4:3, 16:9 or 2.21:1 and requires support for pan vectors so a 4:3 monitor can display widescreen pictures correctly. Clause 5.4 defines the permitted full-screen luminance resolutions and the decoder upconversion behavior needed to display them. In practice, this tells encoders which picture shapes are allowed and tells receiver designers what scaling and windowing they must implement.
Clause 5.5 and 5.6 guide chromaticity and chrominance handling. The document recommends color parameters aligned with ITU-R Recommendation BT.470-2 System B, G, and it describes how chroma downsampling and upsampling should be signaled and treated. That is important for consistent picture color and for decoder memory and reconstruction behavior.
Clause 5.7 recommends a video sequence header followed by an I-frame at least every 500 milliseconds. The note explains the trade-off between faster channel changes and compression efficiency. In practice, service designers balance zap time against bit-rate efficiency.
Audio
Clause 6 limits audio to MPEG-1 single channel, dual channel, joint stereo and stereo, plus MPEG-2 compatible multi-channel audio with basic stereo extraction. Layer I and Layer II are required for decode, while Layer III is optional. This means encoders should stay within the supported broadcast audio profile.
Clause 6.3 and 6.4 constrain bitrate and sampling frequency. The document allows specific bit-rate_index values, requires primary sound services to use 32 kHz, 44.1 kHz or 48 kHz, and allows lower rates only for secondary services. This keeps audio within the expected DVB receiver capability set.
Clause 6.5 and 6.6 require no emphasis and inclusion of the parity check word (crc_check). The IRD should use crc_check for error detection and may apply concealment or muting. In practice, this supports robust decoding and predictable audio handling.
What terms does SIST-TP ETR 154 E2:2005 define?
- Baseline IRD - an Integrated Receiver-Decoder that provides the minimum functionality recommended in the document.
- partial Transport Stream (TS) - a TS formed by removing packets that are not relevant to one selected program, or a selected set of programs.
- Integrated Receiver-Decoder (IRD) - the receiver defined by the guidelines to decode DVB MPEG-2 broadcast services.
- Packetized Elementary Stream (PES) - the packetized form used for carrying audio or video elementary streams in MPEG-2 systems.
- Program Specific Information (PSI) - the MPEG-2 system information used to identify and map programs and streams.
- Service Information (SI) - DVB service tables and descriptors used to identify services and help receivers select them.
- Program Clock Reference (PCR) - the timing reference used to synchronize decoding in the transport stream.
- Conditional Access (CA) - the scrambling and access-control mechanism used to restrict viewing to authorized receivers.
Who uses SIST-TP ETR 154 E2:2005?
SIST-TP ETR 154 E2:2005 is used by broadcasters, receiver manufacturers, encoder designers and engineers working on satellite, cable and terrestrial DVB systems. It is also relevant to teams developing digital VCRs, storage devices and digital interfaces that carry Partial Transport Streams or trick play data.
For a broadcaster or headend engineer, it helps define the stream format and timing that receivers must accept. For an IRD designer, it gives the minimum decode features for video, audio, PSI and SI. For a buyer or quality manager, it is a check list for whether a product or service is aligned with the baseline DVB MPEG-2 profile.
What changed in SIST-TP ETR 154 E2:2005 from the previous edition?
SIST-TP ETR 154 E2:2005 is the second edition and updates ETR 154 Edition 1. The stated update is to cope with changes in the MPEG-2 Systems transport stream in view of Recorder applications and with terrestrial broadcasting applications.
Which standards are used with SIST-TP ETR 154 E2:2005?
- ISO/IEC IS 13818-1 - provides the MPEG-2 Systems rules used for transport streams, PES, PSI and descriptors.
- ISO/IEC IS 13818-2 - provides the MPEG-2 video syntax and profile/level framework used in clause 5.
- ISO/IEC IS 13818-3 - provides the MPEG-2 audio coding rules used in clause 6.
- ISO/IEC IS 13818-9 - provides the real-time interface extension used for Partial Transport Streams.
- ETR 289 - defines the common scrambling system and conditional access behavior referenced for transport and PES scrambling.
- ETS 300 468 - defines DVB Service Information tables, including NIT, PAT/PMT-related DVB usage and other SI structures.
- ETR 211 - gives implementation guidance for Service Information descriptors used with DVB systems.
- ISO/IEC 11172-1 - is the MPEG-1 Systems reference for optional compatibility.
- ITU-T Recommendation J.17 - defines de-emphasis referenced for optional audio decoding.
- EBU Recommendation R.68 - gives the recommended reference tone level for transmission.
- IEC CD-100C/1883 - is cited for Partial Transport Stream transfer definitions.
What does the SIST-TP ETR 154 E2:2005 document contain?
The document contains clause-by-clause implementation guidance for MPEG-2 systems, video and audio in DVB, with explicit encoder and decoder behaviors. It includes transport-stream and PES handling rules, timing guidance, PSI and SI usage, descriptor guidance, and trick mode behavior for storage applications.
It also includes tables for transport and PES scrambling control, a table of example display widths for widescreen aspect ratios, and a table mapping coded luminance resolutions to displayed picture behavior. Clause 5 includes a formula for display sizing and clause 4.2 defines how trick mode data is signaled and interpreted.
For video, the document provides the operating profile, frame rate, aspect ratio, luminance resolution and chromaticity guidance needed to author compatible broadcast bit-streams. For audio, it gives the supported modes, layers, bitrates, sampling frequencies, emphasis behavior and error-checking expectations used for broadcast and receiver design.
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Frequently Asked Questions
SIST-TP ETR 154 E2:2005 is a technical report published by the Slovenian Institute for Standardization (SIST). Its full title is "Digital Video Broadcasting (DVB); DVB implementation guidelines for the use of MPEG-2 Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications". This standard covers: Update of ETR 154 Edition 1 in order to cope with: - changes in MPEG 2 Systems transport stream in view of Recorder applications; - terrestrial broadcasting applications.
Update of ETR 154 Edition 1 in order to cope with: - changes in MPEG 2 Systems transport stream in view of Recorder applications; - terrestrial broadcasting applications.
SIST-TP ETR 154 E2:2005 is classified under the following ICS (International Classification for Standards) categories: 33.170 - Television and radio broadcasting. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST-TP ETR 154 E2:2005 is associated with the following European legislation: Standardization Mandates: T-304. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
SIST-TP ETR 154 E2:2005 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-november-2005
Digitalna videoradiodifuzija (DVB) – Smernice za uvajanje uporabe sistemov MPEG
-2, videa in avdia v satelitskih, kabelskih in prizemnih radiodifuzijskih aplikacijah
Digital Video Broadcasting (DVB); DVB implementation guidelines for the use of MPEG-2
Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications
Ta slovenski standard je istoveten z: ETR 154 Edition 2
ICS:
33.170 Televizijska in radijska Television and radio
difuzija broadcasting
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
ETSI ETR 154
TECHNICAL October 1996
REPORT Second Edition
Source: EBU/CENELEC/ETSI JTC Reference: RTR/JTC-00DVB-27
ICS: 33.060.20
Key words: DVB, digital, video, broadcasting, MPEG, system, TV, audio, satellite, cable, terrestrial
European Broadcasting Union Union Européenne de Radio-Télévision
Digital Video Broadcasting (DVB);
Implementation guidelines for the use of MPEG-2
systems, video and audio
in satellite, cable and terrestrial broadcasting
applications
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: secretariat@etsi.fr
Tel.: +33 4 92 94 42 00 - Fax: +33 4 93 65 47 16
Copyright Notification:
No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1996.
© European Broadcasting Union 1996.
All rights reserved.
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ETR 154: October 1996
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.
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ETR 154: October 1996
Contents
Foreword .5
Introduction.6
1 Scope .7
2 References.7
3 Definitions, symbols and abbreviations.8
3.1 Definitions .8
3.2 Abbreviations .8
4 Systems layer.8
4.1 Broadcast bit-streams and Baseline IRDs.8
4.1.1 Introduction.9
4.1.2 Packetized Elementary Stream (PES) .9
4.1.3 Transport stream system target decoder .9
4.1.4 Transport packet layer.9
4.1.4.1 Null packets .9
4.1.4.2 Transport packet header .9
4.1.4.2.1 transport_error_indicator .9
4.1.4.2.2 transport_priority.9
4.1.4.2.3 transport_scrambling_control .10
4.1.4.2.4 Packet IDentifier (PID) values for
Service Information (SI) Tables .10
4.1.5 Adaptation field.10
4.1.5.1 Random_access_indicator .10
4.1.5.2 elementary_stream_priority_indicator.10
4.1.5.3 Program Clock Reference (PCR) .10
4.1.5.4 Other fields .10
4.1.6 Packetized Elementary Stream (PES) Packet .11
4.1.6.1 stream_id.11
4.1.6.2 PES_scrambling_control .11
4.1.6.3 PES_priority.11
4.1.6.4 copyright and original_or_copy.11
4.1.6.5 Trick mode fields .11
4.1.6.6 additional_copy_info .11
4.1.6.7 Optional fields.12
4.1.6.8 PES_extension_field.12
4.1.7 Program Specific Information (PSI).12
4.1.8 Program and elementary stream descriptors.12
4.1.8.1 video_stream_descriptor and audio_stream_descriptor .12
4.1.8.2 hierarchy_descriptor .13
4.1.8.3 registration_descriptor .13
4.1.8.4 data_stream_alignment_descriptor .13
4.1.8.5 target_background_grid_descriptor.13
4.1.8.6 video_window_descriptor .13
4.1.8.7 Conditional Access CA_descriptor .13
4.1.8.8 ISO_639_Language_descriptor.13
4.1.8.9 system_clock_descriptor .13
4.1.8.10 multiplex_buffer_utilization_descriptor .14
4.1.8.11 copyright_descriptor .14
4.1.8.12 maximum_bitrate_descriptor .14
4.1.8.13 private_data_indicator_descriptor.14
4.1.8.14 STD_descriptor.14
4.1.8.15 IBP_descriptor .14
4.1.8.16 smoothing_buffer_descriptor.14
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ETR 154: October 1996
4.1.9 Compatibility with ISO/IEC 11172-1 [8]. 14
4.1.10 Storage Media Interoperability. 15
4.2 Bit-streams from storage applications and IRDs with digital interfaces . 15
4.2.1 Partial Transport Streams. 15
4.2.2 Decoding of Trick Play data. 15
5 Video. 16
5.1 Profile and level. 16
5.2 Frame rate. 16
5.3 Aspect ratio . 16
5.4 Luminance resolution . 17
5.5 Chromaticity parameters . 18
5.6 Chrominance. 18
5.7 Video sequence header . 19
6 Audio. 19
6.1 Audio mode . 19
6.2 Compression layer . 19
6.3 Bitrate. 20
6.4 Sampling frequency. 20
6.5 Emphasis . 20
6.6 Cyclic redundancy code . 20
History. 21
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ETR 154: October 1996
Foreword
This ETSI Technical Report (ETR) has been produced by the Joint Technical Committee (JTC) of the
European Broadcasting Union (EBU), Comité Européen de Normalisation ELECtrotechnique (CENELEC)
and the European Telecommunications Standards Institute (ETSI). This ETR is based on the DVB
document TM 1214 revision 9, dated September 1996, and it may be converted into an ETS after market
feedback. For this purpose, the wording of an ETS rather than an ETR is used.
ETRs are informative documents resulting from ETSI studies which are not appropriate for European
Telecommunication Standard (ETS) or Interim European Telecommunication Standard (I-ETS) status. An
ETR may be used to publish material which is either of an informative nature, relating to the use or the
application of ETSs or I-ETSs, or which is immature and not yet suitable for formal adoption as an ETS or
an I-ETS.
NOTE: This EBU/ETSI Joint Technical Committee (JTC) was established in 1990 to co-
ordinate the drafting of European Telecommunications Standards (ETSs) in the
specific field of radio, television and data broadcasting.
The EBU is a professional association of broadcasting organizations whose work
includes the co-ordination of its Members' activities in the technical, legal, programme-
making and programme-exchange domains. The EBU has active members in about
60 Countries in the European Broadcasting area; its headquarters is in Geneva *.
* European Broadcasting Union
Case Postale 67
CH-1218 GRAND SACONNEX (Geneva)
Switzerland
Tel: +41 22 717 21 11
Fax: +41 22 717 24 81
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ETR 154: October 1996
Introduction
This ETR presents guidelines covering coding and decoding using the MPEG-2 system defined in
ISO/IEC IS 13818 [1].
The guidelines presented in this ETR for the Integrated Receiver-Decoder (IRD) are intended to represent
a minimum functionality that all IRDs are assumed to either meet or exceed. It is necessary to specify the
minimum IRD functionality for basic parameters, if broadcasters are not to be prevented from ever using
certain features. For example, if a significant population of IRDs were produced that supported only the
Simple Profile, broadcasters would never be able to transmit Main Profile bit-streams.
Where a feature is mandatory, the word "shall" is used and the text is in italic; all other features are
optional. The functionality is specified in the form of constraints on MPEG-2 systems, video and audio
which the IRDs are required to decode correctly.
The specification of these baseline features in no way prohibits IRD manufacturers from including
additional features, and should not be interpreted as stipulating any form of upper limit to the performance.
The guidelines do not cover features, such as the IRD's up-sampling filter, which affect the quality of the
displayed picture rather than whether the IRD is able to decode pictures at all. Such issues are left to the
marketplace.
The guidelines presented for IRDs observe the following principles:
- wherever practical, IRDs should be designed to allow for future compatible extensions to the bit-
stream syntax;
- all "reserved" and "private" bits in MPEG-2 systems, video and audio should be ignored by IRDs not
designed to make use of them.
The rules of operation for the encoders are features and constraints which the encoding system should
adhere to in order to ensure that the transmissions can be correctly decoded by Baseline IRDs. These
may be mandatory or optional. Where a feature or constraint is mandatory, the word "shall" is used and
the text is italic; all other features are optional.
Clauses 4 to 6 provide the guidelines for the Digital Video Broadcasting (DVB) systems layer, video and
audio respectively. For information, some of the key features are summarized below, but clauses 4 to 6
should be consulted for all definitions:
Systems:
- MPEG-2 Transport Stream (TS) is used;
- Service Information (SI) is based on MPEG-2 program-specific information;
- scrambling is as defined in ETR 289 [5];
- conditional access uses the MPEG-2 Conditional Access CA_descriptor;
- Partial Transport Streams are used for digital VCR applications.
Video:
- MPEG-2 Main Profile at Main Level is used;
- the frame rate is 25 Hz;
- encoded pictures may have either 4:3, 16:9 or 2.21:1 aspect ratio;
- IRDs support 4:3 and 16:9 and optionally 2.21:1 aspect ratios;
- IRDs support the use of pan vectors to allow a 4:3 monitor to give a full-screen display of a 16:9
coded picture;
- IRDs support a full-screen display of 720 x 576 pixels (and a nominal full-screen display of
704 x 576);
- IRDs provide appropriate up-conversion to produce a full-screen display of 544 x 576 and 480 x 576
and a nominal full-screen display of 352 x 576 and 352 x 288 pixels.
Audio:
- MPEG-2 Layer I and Layer II is supported by the IRD;
- the use of Layer II is recommended for the encoded bit-stream;
- IRDs support single channel, dual channel, joint stereo, stereo and the extraction of at least a
stereo pair from MPEG-2 compatible multi-channel audio;
- sampling rates of 32 kHz, 44,1 kHz and 48 kHz are supported by IRDs;
- the encoded bit-stream does not use emphasis.
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ETR 154: October 1996
1 Scope
This ETR provides implementation guidelines for the use of MPEG-2 audio-visual coding in satellite and
cable broadcasting systems offering conventional resolution digital television. Guidelines for devices
equipped with a digital interface intended for digital VCR applications are also given in this ETR. It does
not cover applications such as interactive services or HDTV which are likely to be the subject of
subsequent "Guidelines" documents.
The rules of operation for the encoders are features and constraints which the encoding system should
adhere to in order to ensure that the transmissions can be correctly decoded by Baseline IRDs. These
may be recommended or optional.
2 References
For the purposes of this ETR, the following references apply:
[1] ISO/IEC IS 13818-1 (1994): "Coding of moving pictures and associated audio -
Part 1: Systems".
[2] ISO/IEC IS 13818-2 (1994): "Coding of moving pictures and associated audio -
Part 2: Video".
[3] ISO/IEC IS 13818-3: "Coding of moving pictures and associated audio - Part 3:
Audio".
[4] ISO/IEC IS 13818-9: "Coding of moving pictures and associated audio - Part 9:
Extension for Real-Time-Interface for systems decoders ".
[5] ETR 289: "Digital Video Broadcasting (DVB); Common Scrambling (CS) system
description".
[6] ETS 300 468: "Digital Video Broadcasting (DVB); Specification for Service
Information (SI) in DVB systems".
[7] ETR 211: "Digital broadcasting systems for television, sound and data services;
Guidelines for the usage of Service Information (SI) in Digital Video
Broadcasting (DVB) systems".
[8] ISO/IEC 11172-1: "Information Technology - Coding of moving pictures and
associated audio for digital storage media up to about 1,5 Mbit/s - Part 1:
Systems".
[9] ITU-T Recommendation J.17 (1988): "Pre-emphasis used on sound-programme
circuits".
[10] IEC CD - 100C/1883: Parts 1 and 4.
[11] EBU Recommendation R.68: "Alignment level in digital audio production
equipment and in digital audio recorders".
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ETR 154: October 1996
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of this ETR, the following definitions apply:
Baseline IRD: An IRD which provides the minimum functionality recommended in this ETR.
partial Transport Stream (TS): Bit-stream derived from an MPEG-2 Transport Stream (TS) by removing
those TS packets that are not relevant to one particular selected programme, or a number of selected
programmes.
3.2 Abbreviations
For the purposes of this ETR, the following abbreviations apply:
CA Conditional Access
DVB Digital Video Broadcasting
ES Elementary Stream
ESCR Elementary Stream Clock Reference
I-Frame Intra-coded Frame
IRD Integrated Receiver-Decoder
MPEG Moving Pictures Experts Group
NIT Network Information Table
PAT Program Association Table
PCR Program Clock Reference
PES Packetized Elementary Stream
PID Packet IDentifier
PMT Program Map Table
PSI Program Specific Information
PSW Pan and Scan Window
SI Service Information
STD Standard Target Decoder
TS Transport Stream
VCR Video Cassette Recorder
4 Systems layer
This clause describes the guidelines for encoding the systems layer of MPEG-2 in DVB broadcast bit-
streams, and for decoding this layer in the IRD. The source bit-stream may be transmitted via a satellite,
cable or terrestrial channel, or via a digital interface. Subclause 2.1 applies to the encoding of all
source bitstreams and their decoding by a Baseline IRD. Subclause 2.2 gives specific information relating
to bit-streams transmitted via a digital interface intended for VCR applications and decoding by IRDs
equipped with such an interface.
4.1 Broadcast bit-streams and Baseline IRDs
The multiplexing of baseband signals and associated data conforms to ISO/IEC IS 13818-1 [1]. Some of
the parameters and fields are not used in the DVB System and these restrictions are described below. To
allow full compliance to ISO/IEC IS 13818-1 [1] and upward compatibility with future enhanced versions, a
DVB IRD shall be able to skip over data structures which are currently "reserved", or which correspond to
functions not implemented by the IRD. As an example of this capability, a descriptor tag not yet defined
within the DVB System shall be interpreted as a no-action tag, its length field correctly decoded and
subsequent data skipped.
For the same reason, IRD design should be made under the assumption that any legal structure as
permitted by ISO/IEC IS 13818-1 [1] may occur in the broadcast stream even if presently reserved or
unused. Therefore, the following is assumed:
- private data shall only be acted upon by decoders which are so enabled;
- filling out the bit-stream shall be carried out using the normal stuffing mechanism. Reserved fields
shall not be used for this purpose. Data of reserved fields shall be set to 0xFF.
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ETR 154: October 1996
The headings below in this subclause are based on ISO/IEC IS 13818-1 (1994) [1]. The numbers in
brackets after the headings are the relevant chapter and section headings of ISO/IEC IS 13818-1 [1].
4.1.1 Introduction
(ISO/IEC IS 13818-1 [1], section 0)
MPEG-2 systems specify two types of multiplexed data stream: the transport stream and the program
stream.
Encoding: The transmitted multiplex shall use the transport stream.
Decoding: All Baseline IRDs shall be able to demultiplex the MPEG-2 transport stream. Demultiplexing
of program streams (as described in sections 0.2 and 0.3 of ISO/IEC IS 13818-1 [1]) is
optional.
4.1.2 Packetized Elementary Stream (PES)
(ISO/IEC IS 13818-1 [1], section 0.4)
Encoding: The creation of a physical Packetized Elementary Stream (PES) by an encoder is not
required. ESCR fields and ES rate fields need not be coded.
Decoding: ESCR fields and ES rate fields need not be decoded.
4.1.3 Transport stream system target decoder
(ISO/IEC IS 13818-1 [1], section 2.4.2)
Encoding: The system clock frequency shall conform to the tolerance specified in section 2.4.2.1 of
ISO/IEC IS 13818-1 [1]. It is recommended that the tolerance is within 5 parts per million.
Decoding: The IRD shall operate over the full tolerance range of the system clock frequency specified in
section 2.4.2.1 of ISO/IEC IS 13818-1 [1].
4.1.4 Transport packet layer
(ISO/IEC IS 13818-1 [1], section 2.4.3.2)
4.1.4.1 Null packets
Encoding: The encoding of null packets (those with PID value 0x1FFF) shall be as specified in
ISO/IEC IS 13818-1 [1].
4.1.4.2 Transport packet header
4.1.4.2.1 transport_error_indicator
Encoding: It is recommended that any error detecting devices in a transmission path should set the
transport_error_indicator bit when uncorrectable errors are detected.
Decoding: The transport_error_indicator flag is set in the transmitted stream it is recommended that
the IRD should then invoke a suitable concealment or error recovery mechanism.
4.1.4.2.2 transport_priority
Decoding: The transport_priority bit has no meaning to the IRD, and may be ignored.
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ETR 154: October 1996
4.1.4.2.3 transport_scrambling_control
Encoding: The transport_scrambling_control bits shall be set according to table 1, in accordance with
ETR 289 [5].
Table 1: Coding of transport_scrambling_control bits
Value Description
00 no scrambling of TS packet payload
01 reserved for future DVB use
10 TS packet scrambled with Even key
11 TS packet scrambled with Odd key
Decoding: These bits shall be read by the IRD, and the IRD shall respond in accordance with table1.
4.1.4.2.4 Packet IDentifier (PID) values for Service Information (SI) Tables
Encoding: The assignment of PID values for SI data is given in ETS 300 468 [6].
4.1.5 Adaptation field
(ISO/IEC IS 13818-1 [1], section 2.4.3.4)
4.1.5.1 Random_access_indicator
Encoding: It is recommended that the random_access_indicator bit is set whenever a random access
point occurs in video streams (i.e. video sequence header immediately followed by an I-
frame).
4.1.5.2 elementary_stream_priority_indicator
Decoding: The elementary_stream_priority_indicator bit may be ignored by the IRD.
4.1.5.3 Program Clock Reference (PCR)
Encoding: The time interval between two consecutive PCR values of the same program shall not
exceed 100 milliseconds as specified in section 2.7.3 of ISO/IEC IS 13818-1 [1]. It is
recommended that this interval should be no greater than 40 milliseconds.
Decoding: The IRD shall operate correctly with PCRs for a program arriving at intervals not exceeding
100 milliseconds.
4.1.5.4 Other fields
This subclause covers the following fields:
- original_program_clock_reference_base;
- original_program_clock_reference_extension;
- splice_countdown;
- private_data_byte;
- adaptation_field_extension (including fields within).
Encoding: These fields are optional in a DVB bit-stream. The flags that indicate the presence or
absence of each of these fields shall be set appropriately.
Decoding: IRDs shall be able to accept bit-streams which contain these fields. IRDs may ignore the data
within the fields.
Page 11
ETR 154: October 1996
4.1.6 Packetized Elementary Stream (PES) Packet
(ISO/IEC IS 13818-1 [1], section 2.4.3.6)
4.1.6.1 stream_id
Encoding: Within a program, no two elementary streams shall have the same stream_id.
4.1.6.2 PES_scrambling_control
Encoding: The PES_scrambling_
...