ISO/IEC 23094-3:2022

INTERNATIONAL ISO/IEC
STANDARD 23094-3
First edition
2022-09
Information technology — General
video coding —
Part 3:
Conformance and reference software
for low complexity enhancement
video coding
Technologies de l'information — Codage vidéo général —
Partie 3: Conformité et logiciel de référence pour le codage vidéo
d'amélioration de faible complexité
Reference number
© ISO/IEC 2022
© ISO/IEC 2022
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Published in Switzerland
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© ISO/IEC 2022 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Conventions . 2
6 Conformance testing for ISO/IEC 23094-2 . 3
6.1 General . 3
6.2 Bitstream conformance . 3
6.3 Decoder conformance . 3
6.4 Procedure to test bitstreams . 3
6.5 Procedure to test decoder conformance . 4
6.5.1 Conformance bitstreams . 4
6.5.2 Contents of the bitstream file . 4
6.5.3 Operation modes for decoder conformance testing . 4
6.5.4 Requirements on output of the decoding process and timing . 4
6.5.5 Recommendations. 5
6.5.6 Static tests for output order conformance . 5
6.5.7 Dynamic tests for output timing conformance . 5
6.5.8 Decoder conformance test of a particular profile and level . 6
6.6 Specification of the test bitstreams . 6
6.6.1 General . 6
6.6.2 Test bitstreams . 7
6.7 Normative test suites for ISO/IEC 23094-2. 18
7 Reference software description .21
7.1 General . 21
7.2 LTM repository .22
7.3 Encoder usage . 22
7.4 Decoder usage .23
Annex A (informative) Information on accuracy tolerance of decoding implementations.25
Annex B (informative) Demultiplexing of test bitstreams .26
Bibliography .27
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© ISO/IEC 2022 – All rights reserved

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).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC
list of patent declarations received (see https://patents.iec.ch).
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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.
A list of all parts in the ISO/IEC 23094 series can be found on the ISO and IEC websites.
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.
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© ISO/IEC 2022 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 23094-3:2022(E)
Information technology — General video coding —
Part 3:
Conformance and reference software for low complexity
enhancement video coding
1 Scope
This document specifies a set of tests and procedures designed to verify whether bitstreams and
decoders meet normative requirements specified in ISO/IEC 23094-2.
An encoder can claim conformance to ISO/IEC 23094-2 if the bitstreams that it generates are conforming
bitstreams. Characteristics of coded bitstreams and decoders are defined in ISO/IEC 23094-2. Decoder
characteristics define the properties and capabilities of the applied decoding process. The capabilities
of a decoder specify which bitstreams the decoder can decode and reconstruct. A bitstream can be
decoded by a decoder if the characteristics of the bitstream are within the specified decoder capabilities.
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/IEC 23094-2:2021, Information technology – General video coding — Part 2: Low complexity
enhancement video coding
ISO/IEC 14882, Programming languages — C++
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 23094-2 and the following
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/
3.1
bitstream
sequence of bits in the form of a NAL unit stream or a raw bitstream, that forms the representation of
coded pictures and associated data forming one or more coded video sequences
3.2
decoder
embodiment of a process that operates on a bitstream (3.1) and may conform to the decoding process
requirements specified for conformance
Note 1 to entry: The decoder does not include the display process, which is outside the scope of this document.
© ISO/IEC 2022 – All rights reserved

3.3
encoder
embodiment of a process that produces a bitstream (3.1)
Note 1 to entry: The process is not specified in this document (except in regard to identification of the reference
software encoder).
3.4
reference software decoder
software which may decode a bitstream (3.1) encoded according to the syntax structure and which is
accompanying this document
3.5
reference software encoder
encoding software which is accompanying this document
3.6
test base bitstream
bitstream (3.1) that is conformant to Rec. ITU-T H.264 | ISO/IEC 14496-10 or Rec. ITU-T H.265 |
ISO/IEC 23008-2
3.7
test bitstream
bitstream (3.1) that is the combination of a test base bitstream (3.6) and a test enhancement bitstream
(3.8)
3.8
test enhancement bitstream
bitstream (3.1) that is conformant to ISO/IEC 23094-2
4 Abbreviated terms
For the purposes of this document, the abbreviated terms given in ISO/IEC 23094-2 and the following
apply.
API Application programming interface
AVC Advanced video coding
EVC Essential video coding
HEVC High efficiency video coding
LTM LCEVC test model
VVC Versatile video coding
5 Conventions
For the purposes of this document, relevant conventions are specified in of ISO/IEC 23094-2:2021,
Clause 5.
© ISO/IEC 2022 – All rights reserved

6 Conformance testing for ISO/IEC 23094-2
6.1 General
The following subclauses specify normative tests for verifying conformance of video bitstreams as well
as decoders. Those normative tests make use of test data (bitstream test suites) provided as an electronic
attachment to this document and the reference software decoder specified in ISO/IEC 23094-2.
For the purpose of testing according to 6.5, test bitstreams are provided in the bitstream test suite. In
the following subclauses, the normative tests use the test bitstreams for verifying the conformance of
the decoding process of the test enhancement bitstreams.
A test base bitstream is conformant in accordance with the respective International Standard it
implements. The conformance testing of the test base bitstream is not in the scope of this document.
This document includes an electronic attachment containing the conformance bitstreams identified
within the text and the reference software. The electronic attachment is available at the following
address: https:// standards .iso .org/ iso -iec/ 23094/ -3/ ed -1/ en/ .
6.2 Bitstream conformance
Bitstream conformance for ISO/IEC 23094-2 is specified by ISO/IEC 23094-2:2021, C.4.
6.3 Decoder conformance
Decoder conformance for ISO/IEC 23094-2 is specified by ISO/IEC 23094-2:2021, C.5.
6.4 Procedure to test bitstreams
A bitstream that claims conformance with ISO/IEC 23094-2 shall pass the followin
...