ISO/IEC 23008-2:2025

International
Standard
ISO/IEC 23008-2
Sixth edition
Information technology — High
2025-03
efficiency coding and media
delivery in heterogeneous
environments —
Part 2:
High efficiency video coding
Technologies de l'information — Codage à haute efficacité et
livraison des medias dans des environnements hétérogènes —
Partie 2: Codage vidéo à haute efficacité
Reference number
© ISO/IEC 2025
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© ISO/IEC 2025 – All rights reserved
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All rights reserved. Unless otherwise specified, or required in the context of its implementation,
no part of this publication may be reproduced or utilized otherwise in any form or by any means,
electronic or mechanical, including photocopying, or posting on the internet or an intranet,
without prior written permission. Permission can be requested from either ISO at the address
below or ISO's member body in the country of the requester.
ISO Copyright Office
CP 401 • CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland.
© ISO/IEC 2025 – All rights reserved
ii
Contents Page
Foreword . vii
Introduction . ix
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 22
5 Conventions. 24
5.1 General . 24
5.2 Arithmetic operators . 24
5.3 Logical operators . 25
5.4 Relational operators . 25
5.5 Bit-wise operators . 25
5.6 Assignment operators. 26
5.7 Range notation . 26
5.8 Mathematical functions . 26
5.9 Order of operation precedence . 27
5.10 Variables, syntax elements, and tables . 28
5.11 Text description of logical operations . 29
5.12 Processes . 31
6 Bitstream and picture formats, partitionings, scanning processes, and neighbouring
relationships . 31
6.1 Bitstream formats . 31
6.2 Source, decoded, and output picture formats . 31
6.3 Partitioning of pictures, slices, slice segments, tiles, CTUs, and CTBs . 34
6.3.1 Partitioning of pictures into slices, slice segments, and tiles . 34
6.3.2 Block and quadtree structures . 36
6.3.3 Spatial or component-wise partitionings . 37
6.4 Availability processes . 37
6.4.1 Derivation process for z-scan order block availability . 37
6.4.2 Derivation process for prediction block availability . 38
6.5 Scanning processes . 40
6.5.1 CTB raster and tile scanning conversion process . 40
6.5.2 Z-scan order array initialization process . 41
6.5.3 Up-right diagonal scan order array initialization process . 41
6.5.4 Horizontal scan order array initialization process . 42
6.5.5 Vertical scan order array initialization process . 42
© ISO/IEC 2025 – All rights reserved
iii
6.5.6 Traverse scan order array initialization process . 43
7 Syntax and semantics . 43
7.1 Method of specifying syntax in tabular form . 43
7.2 Specification of syntax functions and descriptors . 44
7.3 Syntax in tabular form . 46
7.3.1 NAL unit syntax . 46
7.3.2 Raw byte sequence payloads, trailing bits, and byte alignment syntax . 47
7.3.3 Profile, tier and level syntax . 56
7.3.4 Scaling list data syntax . 59
7.3.5 Supplemental enhancement information message syntax . 60
7.3.6 Slice segment header syntax . 60
7.3.7 Short-term reference picture set syntax . 65
7.3.8 Slice segment data syntax . 66
7.4 Semantics . 81
7.4.1 General . 81
7.4.2 NAL unit semantics . 81
7.4.3 Raw byte sequence payloads, trailing bits, and byte alignment semantics . 92
7.4.4 Profile, tier, and level semantics . 115
7.4.5 Scaling list data semantics . 119
7.4.6 Supplemental enhancement information message semantics . 122
7.4.7 Slice segment header semantics . 122
7.4.8 Short-term reference picture set semantics . 132
7.4.9 Slice segment data semantics . 135
8 Decoding process . 151
8.1 General decoding process . 151
8.1.1 General . 151
8.1.2 CVSG decoding process . 151

8.1.3 Decoding process for a coded picture with nuh_layer_id equal to 0 . 152
8.2 NAL unit decoding process . 154
8.3 Slice decoding process . 155
8.3.1 Decoding process for picture order count . 155
8.3.2 Decoding process for reference picture set . 156
8.3.3 Decoding process for generating unavailable reference pictures . 161
8.3.4 Decoding process for reference picture lists construction . 162
8.3.5 Decoding process for collocated picture and no backward prediction flag . 163
8.4 Decoding process for coding units coded in intra prediction mode . 164
8.4.1 General decoding process for coding units coded in intra prediction mode . 164
© ISO/IEC 2025 – All rights reserved
iv
8.4.2 Derivation process for luma intra prediction mode . 169
8.4.3 Derivation process for chroma intra prediction mode . 171
8.4.4 Decoding process for intra blocks . 172
8.5 Decoding process for coding units coded in inter prediction mode . 185
8.5.1 General decoding process for coding units coded in inter prediction mode . 185
8.5.2 Inter prediction process . 186
8.5.3 Decoding process for prediction units in inter prediction mode . 190
8.5.4 Decoding process for the residual signal of coding units coded in inter
prediction mode .22 3
8.6 Scaling, transformation and array construction process prior to deblocking filter
process .22 7
8.6.1 Derivation process for quantization parameters . 227
8.6.2 Scaling and transformation process . 229
8.6.3 Scaling process for transform coefficients . 231
8.6.4 Transformation process for scaled transform coefficients . 232
8.6.5 Residual modification process for blocks using a transform bypass . 235
8.6.6 Residual modification process for transform blocks using cross-component
prediction .23 6
8.6.7 Picture construction process prior to in-loop filter process . 236
8.6.8 Residual modification process for blocks using adaptive colour transform . 237
8.7 In-loop filter process .23 9
8.7.1 General .23 9
8.7.2 Deblocking filter process . 240
8.7.3 Sample adaptive offset process . 258
9 Parsing process . 261
9.1 General .26 1
9.2 Parsing process for 0-th order Exp-Golomb codes . 261
9.2.1 General .26 1
9.2.2 Mapping process for signed Exp-Golomb codes . 263
9.3 CABAC parsing process for slice segment data . 263
9.3.1 General .26 3
9.3.2 Initialization process . 266
9.3.3 Binarization process . 280
9.3.4 Decoding process flow . 290
9.3.5 Arithmetic encoding process . 306
© ISO/IEC 2025 – All rights reserved
v
10 Sub-bitstream extraction process . 313
Annex A (normative) Profiles, tiers and levels . 315
Annex B (normative) Byte stream format . 345
Annex C (normative) Hypothetical reference decoder . 348
Annex D (normative) Supplemental enhancement information . 369
Annex E (normative) Video usability information . 537
Annex F (normative) Common specifications for multi-layer extensions . 568
Annex G (normative) Multiview high efficiency video coding . 727
Annex H (normative) Scalable high efficiency video coding . 759
Annex I (normative) 3D high efficiency video coding . 790
Bibliography . 915
© ISO/IEC 2025 – All rights reserved
vi
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical activity.
ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
ISO and IEC draw attention to the possibility that the implementation of this document may involve the
use of (a) patent(s). ISO and IEC take no position concerning the evidence, validity or applicability of
any claimed patent rights in respect thereof. As of the date of publication of this document, ISO and IEC
had received notice of (a) patent(s) which may be required to implement this document. However,
implementers are cautioned that this may not represent the latest information, which may be obtained
from the patent database available at www.iso.org/patents and https://patents.iec.ch. ISO and IEC shall
not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information, in collaboration
with ITU-T (as Rec. ITU-T H.265).
This sixth edition cancels and replaces the fifth edition (ISO/IEC 23008-2:2023), which has been
technically revised.
The main changes are as follows:
 the specification of six additional profiles (the Multiview Extended, Multiview Extended 10,
Multiview Monochrome, Multiview Monochrome 10, Multiview Monochrome 12, and Multiview
Monochrome 16 profiles);
 the specification of three additional colour type identifiers;
 the specification of three additional SEI messages for neural network post-filter characteristics
(NNPFC), neural-network post-filter activation (NNPFA), and phase indication (through
referencing to Rec. ITU-T H.274 | ISO/IEC 23002-7).
A list of all parts in the ISO/IEC 23008 series can be found on the ISO and IEC websites.
© ISO/IEC 2025 – All rights reserved
vii
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 and www.iec.ch/national-
committees.
© ISO/IEC 2025 – All rights reserved
viii
Introduction
As the costs for both processing power and memory have reduced, network support for coded video
data has diversified, and advances in video coding technology have progressed. The need has arisen for
an industry standard for compressed video representation with substantially increased coding
efficiency and enhanced robustness to network environments. Toward these ends, the ITU-T Video
Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG) formed a Joint
Collaborative Team on Video Coding (JCT-VC) in 2010 and a Joint Collaborative Team on 3D Video
Coding Extension Development (JCT-3V) in 2012 for development of a new
Recommendation | International Standard. This document was developed in the JCT-VC and the JCT-3V.
Purpose
This document was developed in response to the growing need for higher compression of moving
pictures for various applications such as videoconferencing, digital storage media, television
broadcasting, internet streaming, and communications. It is also designed to enable the use of the coded
video representation in a flexible manner for a wide variety of network environments as well as to
enable the use of multi-core parallel encoding and decoding devices. The use of this document allows
motion video to be manipulated as a form of computer data and to be stored on various storage media,
transmitted and received over existing and future networks and distributed on existing and future
broadcasting channels. Supports for higher bit depths and enhanced chroma formats, including the use
of full-resolution chroma are provided. Support for scalability enables video transmission on networks
with varying transmission conditions and other scenarios involving multiple bit rate services. Support
for multiview enables representation of video content with multiple camera views and optional
auxiliary information. Support for 3D enables joint representation of video content and depth
information with multiple camera views.
Applications
This document is designed to cover a broad range of applications for video content including but not
limited to the following:
— broadcast (cable TV on optical networks / copper, satellite, terrestrial, etc.);
— camcorders;
— content production and distribution;
— digital cinema;
— home cinema;
— internet streaming, download and play;
— medical imaging;
— mobile streaming, broadcast and communications;
— real-time conversational services (videoconferencing, videophone, telepresence, etc.);
— remote video surveillance;
— storage media (optical disks, digital video tape recorder, etc.);
© ISO/IEC 2025 – All rights reserved
ix
— wireless display.
Publication and versions of this document
This document has been jointly developed by ITU-T Video Coding Experts Group (VCEG) and the
ISO/IEC Moving Picture Experts Group (MPEG). It is published as technically-aligned twin text in both
ITU-T and ISO/IEC. As the basis text has been drafted to become both an ITU-T Recommendation and an
ISO/IEC International Standard, the term "Specification" (with capitalization to indicate that it refers to
the whole of the text) is used herein when the text refers to itself.
This is the tenth version of this document and the sixth edition published by ISO/IEC.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 1 refers to the first approved version of this document. The
first edition published by ISO/IEC as ISO/IEC 23008-2:2013 corresponded to the first version.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 2 refers to the integrated text additionally containing
format range extensions, scalability extensions, multiview extensions, additional supplement
enhancement information, and corrections to various minor defects in the prior content of the
specification. The second edition published by ISO/IEC as ISO/IEC 23008-2:2015 corresponded to the
second version.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 3 refers to the integrated text additionally containing 3D
extensions, additional supplement enhancement information, and corrections to various minor defects
in the prior content of the specification.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 4 refers to the integrated text additionally containing
screen content coding extensions profiles, scalable range extensions profiles, additional high
throughput profiles, additional supplement enhancement information, additional colour representation
identifiers, and corrections to various minor defects in the prior content of the specification. The third
edition published by ISO/IEC as ISO/IEC 23008-2:2017 corresponded to the fourth version.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 5 refers to the integrated text additionally containing
additional SEI messages that include omnidirectional video specific SEI messages, a Monochrome 10
profile, a Main 10 Still Picture profile, and corrections to various minor defects in the prior content of
the specification.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 6 refers to the integrated text additionally containing
additional SEI messages for SEI manifest and SEI prefix, and corrections to various minor defects in the
prior content of the specification.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 7 refers to the integrated text additionally containing the
fisheye video information SEI message and the annotated regions SEI message, and corrections to
various minor defects in the prior content of the specification. The fourth edition published by ISO/IEC
as ISO/IEC 23008-2:2020 corresponded to the seventh version.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 8 refers to the integrated text additionally containing the
shutter interval SEI message and corrections to various minor defects in the prior content of the
specification.
Rec. ITU-T H.265 | ISO/IEC 23008-2 version 9 refers to the integrated text additionally containing
specification of levels 6.3, 7, 7.1, and 7.2, the specification of level 8.5 for the video profiles, and
corrections to various minor defects in the prior content of the specification. This fifth edition published
by ISO/IEC as ISO/IEC 23008-2:2023 corresponds to the ninth version.
© ISO/IEC 2025 – All rights reserved
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Rec. ITU-T H.265 | ISO/IEC 23008-2 version 10 (the current version) refers to the integrated text
additionally containing specification of six additional profiles (the Multiview Extended, Multiview
Extended 10, Multiview Monochrome, Multiview Monochrome 10, Multiview Monochrome 12, and
Multiview Monochrome 16 profiles), the specification of three additional colour type identifiers, the
specification of three additional SEI messages for neural network post-filter characteristics (NNPFC),
neural-network post-filter activation (NNPFA), and phase indication (through referencing to Rec. ITU-T
H.274 | ISO/IEC 23002-7), and corrections to various minor defects in the prior content of the
specification. This sixth edition published by ISO/IEC as ISO/IEC 23008-2:202X corresponds to the
tenth version.
Profiles, tiers, and levels
This document is designed to be generic in the sense that it serves a wide range of applications, bit
rates, resolutions, qualities, and services. Applications should cover, among other things, digital storage
media, television broadcasting, and real-time communications. In the course of creating this document,
various requirements from typical applications have been considered, necessary algorithmic elements
have been developed, and these have been integrated into a single syntax. Hence, this document will
facilitate video data interchange among different applications.
Considering the practicality of implementing the full syntax of this document, however, a limited
number of subsets of the syntax are also stipulated by means of "profiles", "tiers", and "levels". These
and other related terms are formally defined in Clause 3.
A “profile” is a subset of the entire bitstream syntax that is specified in this document. Within the
bounds imposed by the syntax of a given profile it is still possible to require a very large variation in the
performance of encoders and decoders depending upon the values taken by syntax elements in the
bitstream such as the specified size of the decoded pictures. In many applications, it is currently neither
practical nor economical to implement a decoder capable of dealing with all hypothetical uses of the
syntax within a particular profile.
In order to deal with this problem, "tiers" and "levels" are specified within each profile. A level of a tier
is a specified set of constraints imposed on values of the syntax elements in the bitstream. These
constraints may be simple limits on values. Alternatively they may take the form of constraints on
arithmetic combinations of values (e.g. picture width multiplied by picture height multiplied by number
of pictures decoded per second). A level specified for a lower tier is more constrained than a level
specified for a higher tier.
Coded video content conforming to this document uses a common syntax. In order to achieve a subset
of the complete syntax, flags, parameters, and other syntax elements are included in the bitstream that
signal the presence or absence of syntactic elements that occur later in the bitstream.
Overview of the design characteristics
The coded representation specified in the syntax is designed to enable a high compression capability for
a desired image or video quality. The algorithm is typically not lossless, as the exact source sample
values are typically not preserved through the encoding and decoding processes. A number of
techniques may be used to achieve highly efficient compression. Encoding algorithms (not specified in
this Recommendation | International Standard) may select between inter and intra coding for block-
shaped regions of each picture. Inter coding uses motion vectors for block-based inter prediction to
exploit temporal statistical dependencies between different pictures. Intra coding uses various spatial
prediction modes to exploit spatial statistical dependencies in the source signal for a single picture.
Motion vectors and intra prediction modes may be specified for a variety of block sizes in the picture.
The prediction residual may then be further compressed using a transform to remove spatial
correlation inside the transform block before it is quantized, producing a possibly irreversible process
that typically discards less important visual information while forming a close approximation to the
© ISO/IEC 2025 – All rights reserved
xi
source samples. Finally, the motion vectors or intra prediction modes may also be further compressed
using a variety of prediction mechanisms, and, after prediction, are combined with the quantized
transform coefficient information and encoded using arithmetic coding.
How to read this document
It is suggested that the reader starts with Clause 1 (Scope) and moves on to Clause 3 (Terms and
definitions). Clause 6 should be read for the geometrical relationship of the source, input, and output of
the decoder. Clause 7 (Syntax and semantics) specifies the order to parse syntax elements from the
bitstream. See 7.1 to 7.3 for syntactical order and see 7.4 for semantics; e.g. the scope, restrictions, and
conditions that are imposed on the syntax elements. The actual parsing for most syntax elements is
specified in Clause 9 (Parsing process). Clause 10 (Sub-bitstream extraction process) specifies the sub-
bitstream extraction process. Finally, Clause 8 (Decoding process) specifies how the syntax elements
are mapped into decoded samples. Throughout reading this document, the reader should refer to
Clauses 2 (Normative references), 4 (Abbreviated terms), and 5 (Conventions) as needed. Annexes A
through I also form an integral part of this document.
Annex A specifies profiles each being tailored to certain application domains, and defines the so-called
tiers and levels of the profiles. Annex B specifies syntax and semantics of a byte stream format for
delivery of coded video as an ordered stream of bytes. Annex C specifies the hypothetical reference
decoder, bitstream conformance, decoder conformance, and the use of the hypothetical reference
decoder to check bitstream and decoder conformance. Annex D specifies syntax and semantics for
supplemental enhancement information message payloads. Annex E specifies syntax and semantics of
the video usability information parameters of the sequence parameter set. Annex F specifies general
multi-layer support for bitstreams and decoders. Annex G contains support for multiview coding. Annex
H contains support for scalability. Annex I contains support for 3D coding.
Throughout this document, statements appearing with the preamble "NOTE" are informative and are
not an integral part of this document.

© ISO/IEC 2025 – All rights reserved
xii
International Standard ISO/IEC 23008-2:2025(en)

Information technology — High efficiency coding and
media delivery in heterogeneous environments —
Part 2:
High efficiency video coding
1 Scope
This document specifies high efficiency video coding.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/CIE 11664-1, Colorimetry — Part 1: CIE standard colorimetric observers
ISO 12232, Photography — Digital still cameras — Determination of exposure index, ISO speed ratings,
standard output sensitivity, and recommended exposure index
ISO/IEC 10646, Information technology — Universal Coded Character Set (UCS)
ISO/IEC 11578, Information technology — Open Systems Interconnection — Remote Procedure Call (RPC)
ISO/IEC 23001-11, Information technology — MPEG systems technologies — Part 11: Energy-efficient
media consumption (green metadata)
Recommendation ITU-T H.274 | ISO/IEC 23002-7, Versatile supplemental enhancement information
messages for coded video bitstreams.
Recommendation ITU-T T.35, Procedure for the allocation of ITU-T defined codes for non-standard
facilities
IETF RFC 1321, The MD5 Message-Digest Algorithm
IETF RFC 5646, Tags for Identifying Languages
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
© ISO/IEC 2025 – All rights reserved
3.1
access unit
set of NAL units (3.87) that are associated with each other according to a specified classification rule,
are consecutive in decoding order (3.44), and contain exactly one coded picture (3.25) with nuh_layer_id
equal to 0
Note 1 to entry: In addition to containing the VCL NAL units (3.181) of the coded picture with nuh_layer_id equal
to 0, an access unit can also contain non-VCL NAL units. The decoding of an access unit with the decoding process
specified in Clause 8 always results in a decoded picture with nuh_layer_id equal to 0.
Note 2 to entry: An access unit is defined differently in Annex F and might not contain a coded picture with
nuh_layer_id equal to 0.
3.2
AC transform coefficient
transform coefficient (3.175) for which the frequency index (3.58) in at least one of the two dimensions
is non-zero
3.3
associated IRAP picture
previous IRAP picture (3.71) in decoding order (3.44) (when present)
3.4
associated non-VCL NAL unit
non-VCL NAL unit (3.91) (when present) for a VCL NAL unit (3.180) where the VCL NAL unit is the
associated VCL NAL unit (3.5) of the non-VCL NAL unit
3.5
associated VCL NAL unit
preceding VCL NAL unit (3.180) in decoding order (3.44) for a non-VCL NAL unit (3.91) with
nal_unit_type equal to EOS_NUT, EOB_NUT, FD_NUT, or SUFFIX_SEI_NUT, or in the ranges of
RSV_NVCL45.RSV_NVCL47 or UNSPEC56.UNSPEC63; or otherwise, the next VCL NAL unit in decoding
order
3.6
azimuth circle
circle on a sphere connecting all points with the same azimuth value
Note 1 to entry: An azimuth circle is always a great circle like a longitude line on the earth.
3.7
base layer
layer in which all NAL units (3.87) have nuh_layer_id equal to 0
3.8
bin
one bit of a bin string (3.11)
3.9
binarization
set of bin strings (3.11) for all possible values of a syntax element (3.162)
3.10
binarization process
unique mapping process of all possible values of a syntax element (3.162) onto a set of bin strings (3.11)
© ISO/IEC 2025 – All rights reserved
3.11
bin string
intermediate binary representation of values of syntax elements (3.162) from the binarization (3.9) of
the syntax element
3.12
bi-predictive slice
B slice
slice (3.143) that is decoded using intra prediction (3.69) or using inter prediction (3.67) with at most
two motion vectors (3.86) and reference indices (3.127) to predict the sample values of each block (3.14)
3.13
bitstream
sequence of bits, in the form of a NAL unit stream (3.88) or a byte stream (3.21), that forms the
representation of coded pictures (3.25) and associated data forming one or more CVSs (3.30)
3.14
block
MxN (M-column by N-row) array of samples or an MxN array of transform coefficients (3.175)
3.15
broken link
location in a bitstream (3.13) at which it is indicated that some subsequent pictures (3.99) in decoding
order (3.44) may contain serious visual artefacts due to unspecified operations performed in the
generation of the bitstream
3.16
broken link access access unit
BLA access unit
access unit (3.1) in which the coded picture (3.25) with nuh_layer_id equal to 0 is a BLA picture (3.17)
3.17
broken link access picture
BLA picture
IRAP picture (3.71) for which each VCL NAL unit (3.181) has nal_unit_type equal to BLA_W_LP,
BLA_W_RADL, or BLA_N_LP
Note 1 to entry: A BLA picture does not refer to any pictures other than itself for inter prediction (3.67) in its
decoding process (3.45), and can be the first picture in the bitstream (3.13) in decoding order, or can appear later
in the bitstream. Each BLA picture begins a new CVS (3.30), and has the same effect on the decoding process as an
IDR picture (3.65). However, a BLA picture contains syntax elements (3.162) that specify a non-empty RPS (3.132).
When a BLA picture for which each VCL NAL unit has nal_unit_type equal to BLA_W_LP, it can have associated
RASL pictures, which are not output by the decoder and can be non-decodable, as they can contain references to
pictures that are not present in the bitstream. When a BLA picture for which each VCL NAL unit has nal_unit_type
equal to BLA_W_LP, it can also have associated RADL pictures, which are specified to be decoded. When a BLA
picture for which each VCL NAL unit has nal_unit_type equal to BLA_W_RADL, it does not have associated RASL
pictures but can have associated RADL pictures. When a BLA picture for which each VCL NAL unit has
nal_unit_type equal to BLA_N_LP, it does not have any associated leading pictures.
3.18
buffering period
set of access units (3.1) starting with an access unit that contains a buffering period SEI message and
containing all subsequent access units in decoding order (3.44) up to but not including the next access
unit (when present) that contains a buffering period SEI message
© ISO/IEC 2025 – All rights reserved
3.19
byte
sequence of 8 bits, within which, when written or read as a sequence of bit values, the left-most and
right-most bits represent the most and least significant bits, respectively
3.20
byte-aligned
position in a bitstream (3.13) is byte-aligned when the position is an integer multiple of 8 bits from the
position of the first bit in the bitstream and a bit or byte (3.19) or syntax element (3.162) is said to be
byte-aligned when the position at which it appears in a bitstream is byte-aligned
3.21
byte stream
sequence of bytes forming an encapsulation of a NAL unit stream (3.88)
...