Information technology -- Coded representation of immersive media

This document specifies the syntax, semantics and decoding for visual volumetric media using video‑based coding methods. This document also specifies processes that can be needed for reconstruction of visual volumetric media, which can also include additional processes such as post‑decoding, pre-reconstruction, post‑reconstruction and adaptation.

Technologie de l'information -- Représentation codée de média immersifs

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Publication Date
17-Jun-2021
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9092 - International Standard to be revised
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02-Aug-2021
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INTERNATIONAL ISO/IEC
STANDARD 23090-5
First edition
2021-06
Information technology — Coded
representation of immersive media —
Part 5:
Visual volumetric video-based coding
(V3C) and video-based point cloud
compression (V-PCC)
Technologie de l'information — Représentation codée de média
immersifs —
Partie 5: Codage basé sur la vidéo volumétrique (V3C) et compression
de nuage de points basée sur la vidéo (V-PCC)
Reference number
ISO/IEC 23090-5:2021(E)
ISO/IEC 2021
---------------------- Page: 1 ----------------------
ISO/IEC 23090-5:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2021

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. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO/IEC 2021 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/IEC 23090-5:2021(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

Introduction ................................................................................................................................................................................................................................vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Abbreviated terms ...........................................................................................................................................................................................15

5 Conventions ............................................................................................................................................................................................................16

5.1 General ........................................................................................................................................................................................................16

5.2 Arithmetic operators ......................................................................................................................................................................16

5.3 Logical operators ...............................................................................................................................................................................16

5.4 Relational operators ........................................................................................................................................................................17

5.5 Bit-wise operators.............................................................................................................................................................................17

5.6 Assignment operators ....................................................................................................................................................................18

5.7 Other operators ...................................................................................................................................................................................18

5.8 Mathematical functions ................................................................................................................................................................18

5.9 Order of operation precedence ..............................................................................................................................................19

5.10 Variables, syntax elements and tables .............................................................................................................................19

5.11 Text description of logical operations ..............................................................................................................................21

5.12 Processes ...................................................................................................................................................................................................22

6 Overall V3C characteristics, decoding operations and post-decoding processes ..........................23

6.1 V3C characteristics ...........................................................................................................................................................................23

6.2 V3C bitstream characteristics, decoding operations and post-decoding processes ................25

7 Bitstream format, partitioning and scanning processes .........................................................................................26

7.1 General ........................................................................................................................................................................................................26

7.2 V3C bitstream formats ..................................................................................................................................................................26

7.3 NAL bitstream formats ..................................................................................................................................................................27

7.4 Partitioning of atlas frames into tiles ...............................................................................................................................27

7.5 Tile partition scanning process .............................................................................................................................................28

8 Syntax and semantics ...................................................................................................................................................................................29

8.1 Method of specifying syntax in tabular form .............................................................................................................29

8.2 Specification of syntax functions and descriptors .................................................................................................30

8.3 Syntax in tabular form ...................................................................................................................................................................32

8.3.1 General...................................................................................................................................................................................32

8.3.2 V3C unit syntax ..............................................................................................................................................................33

8.3.3 Byte alignment syntax ..............................................................................................................................................34

8.3.4 V3C parameter set syntax .....................................................................................................................................35

8.3.5 NAL unit syntax ..............................................................................................................................................................38

8.3.6 Raw byte sequence payloads, trailing bits and byte alignment syntax ..........................38

8.3.7 Atlas tile data unit syntax ......................................................................................................................................44

8.3.8 Supplemental enhancement information message syntax.......................................................48

8.4 Semantics ..................................................................................................................................................................................................49

8.4.1 General...................................................................................................................................................................................49

8.4.2 V3C unit semantics......................................................................................................................................................49

8.4.3 Byte alignment semantics .....................................................................................................................................51

8.4.4 V3C parameter set semantics ............................................................................................................................51

8.4.5 NAL unit semantics .....................................................................................................................................................57

8.4.6 Raw byte sequence payloads, trailing bits and byte alignment semantics .................66

8.4.7 Atlas tile data unit semantics .............................................................................................................................79

8.4.8 Supplemental enhancement information message semantics ..............................................87

9 Decoding process ..............................................................................................................................................................................................87

9.1 General decoding process ...........................................................................................................................................................87

© ISO/IEC 2021 – All rights reserved iii
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ISO/IEC 23090-5:2021(E)

9.2 Atlas data decoding process .....................................................................................................................................................88

9.2.1 General atlas data decoding process ...........................................................................................................88

9.2.2 Decoding process for a coded atlas frame ..............................................................................................89

9.2.3 Atlas NAL unit decoding process ....................................................................................................................90

9.2.4 Atlas tile header decoding process ...............................................................................................................90

9.2.5 Decoding process for patch data units .......................................................................................................95

9.2.6 Decoding process of the block to patch map .....................................................................................110

9.2.7 Conversion of tile level patch information to atlas level patch information ..........111

9.3 Occupancy video decoding process ................................................................................................................................113

9.4 Geometry video decoding process ...................................................................................................................................114

9.5 Attribute video decoding process .....................................................................................................................................116

9.6 Sub-bitstream extraction process .....................................................................................................................................119

9.6.1 General................................................................................................................................................................................119

9.6.2 V3C unit extraction ..................................................................................................................................................119

9.6.3 NAL unit extraction process .............................................................................................................................120

10 Pre-reconstruction process ................................................................................................................................................................120

11 Reconstruction process ..........................................................................................................................................................................120

12 Post-reconstruction process .............................................................................................................................................................120

13 Adaptation process .....................................................................................................................................................................................120

14 Parsing process ...............................................................................................................................................................................................121

14.1 General .....................................................................................................................................................................................................121

14.2 Parsing process for 0-th order Exp-Golomb codes ............................................................................................121

14.2.1 General................................................................................................................................................................................121

14.2.2 Mapping process for signed Exp-Golomb codes .............................................................................122

Annex A (normative) Profiles, tiers and levels ...................................................................................................................................123

Annex B (normative) Post-decoding conversion to nominal video formats ........................................................137

Annex C (normative) V3C sample stream format .............................................................................................................................158

Annex D (normative) NAL sample stream format ............................................................................................................................160

Annex E (normative) Atlas hypothetical reference decoder .................................................................................................162

Annex F (normative) Supplemental enhancement information ......................................................................................179

Annex G (normative) Volumetric usability information ...........................................................................................................236

Annex H (normative) Video-based point cloud coding ..............................................................................................................247

Bibliography .........................................................................................................................................................................................................................331

iv © ISO/IEC 2021 – All rights reserved
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ISO/IEC 23090-5:2021(E)
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).

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 http:// patents .iec .ch).

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.

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 23090 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
© ISO/IEC 2021 – All rights reserved v
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ISO/IEC 23090-5:2021(E)
Introduction

Advances in 3D capturing and rendering technologies have unleashed a new wave of innovation in

virtual/augmented/mixed reality (VR/AR/MR) content creation and communication, of which visual

volumetric video is an integral part.

Visual volumetric video, a sequence of visual volumetric frames, if uncompressed, can be represented

by a large amount of data, which can be costly in terms of storage and transmission. This has led to the

need for a high coding efficiency standard for the compression of visual volumetric data.

Visual volumetric frames can be coded by converting the 3D volumetric information into a collection of

2D images and associated data. The converted 2D images can be coded using widely available video and

image coding specifications, such as ISO/IEC 14496-10 and ISO/IEC 23008-2 and the associated data

can be coded with mechanisms specified in this document. The coded images and the associated data

can then be decoded and used to reconstruct the 3D volumetric information. This document specifies

a generic mechanism for visual volumetric video coding, i.e. visual volumetric video-based coding. The

generic mechanism can be used by applications targeting volumetric content, such as point clouds,

immersive video with depth, mesh representations of visual volumetric frames, etc.

In addition to the generic mechanism of coding volumetric content, this document specifies one of the

applications of visual volumetric video-based coding targeting point cloud representations of visual

volumetric frames. In a point cloud sequence, each point cloud frame contains a collection of points.

Each point has a 3D position, i.e., geometry information, and each point can also be associated with a

number of attributes, such as colour, reflectance, surface normal, etc.

The International Organization for Standardization (ISO) and International Electrotechnical

Commission (IEC) draw attention to the fact that it is claimed that compliance with this document may

involve the use of a patent.

ISO and IEC take no position concerning the evidence, validity and scope of this patent right.

The holder of this patent right has assured ISO and IEC that he/she is willing to negotiate licences under

reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this

respect, the statement of the holder of this patent right is registered with ISO and IEC. Information may

be obtained from the patent database available at www .iso .org/ patents.

Attention is drawn to the possibility that some of the elements of this document may be the subject

of patent rights other than those in the patent database. ISO and IEC shall not be held responsible for

identifying any or all such patent rights.
vi © ISO/IEC 2021 – All rights reserved
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INTERNATIONAL STANDARD ISO/IEC 23090-5:2021(E)
Information technology — Coded representation of
immersive media —
Part 5:
Visual volumetric video-based coding (V3C) and video-
based point cloud compression (V-PCC)
1 Scope

This document specifies the syntax, semantics and decoding for visual volumetric media using

video-based coding methods. This document also specifies processes that can be needed for

reconstruction of visual volumetric media, which can also include additional processes such as

post-decoding, pre-reconstruction, post-reconstruction and adaptation.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitute 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.

IEEE 754-2019, IEEE Standard for Floating-Point Arithmetic
IETF RFC 1321The MD5 Message-Digest Algorithm
IETF RFC 5646Tags for Identifying Languages
ISO/IEC 10646, Information technology — Universal Coded Character Set (UCS)

ISO/IEC 14496-10:2020, Information technology — Coding of audio-visual objects — Part 10: Advanced

Video Coding

ISO/IEC 14496-12, Information technology — Coding of audio-visual objects — Part 12: ISO base media

file format

ISO/IEC 14496-15, Information technology — Coding of audio-visual objects — Part 15: Carriage of

network abstraction layer (NAL) unit structured video in the ISO base media file format

ISO/IEC 23008-2:2020, Information technology — High efficiency coding and media delivery in

heterogeneous environments — Part 2: High efficiency video coding

ISO/IEC 23090-3, Information technology — Coded representation of immersive media — Part 3: Versatile

video coding

ISO/IEC 23091-2, Coding-independent code points for video signal type identification

Rec. ITU-T T.35:2000, Procedure for the allocation of ITU-T defined codes for non standard facilities

Rec. ITU-T H.271:2006, Video back-channel messages for conveyance of status information and requests

from a video receiver to a video sender
© ISO/IEC 2021 – All rights reserved 1
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ISO/IEC 23090-5:2021(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
3D bounding box

volume defined as a cuboid solid having six rectangular faces placed at right angles

3.2
associated non-ACL NAL unit

non-ACL NAL unit (3.78) that is associated with an ACL NAL unit (3.6) for the purpose of decoding or

other operations specified by this document
3.3
associated ACL NAL unit

preceding ACL NAL unit (3.6) in decoding order for a non-ACL NAL unit (3.78) with nal_unit_type equal

to NAL_EOS, NAL_EOB, NAL_FD, NAL_SUFFIX_NSEI, or NAL_SUFFIX_ESEI, or in the ranges of NAL_

RSV_NACL_48..NAL_RSV_NACL_52 or NAL_UNSPEC_53..NAL_UNSPEC_63; or otherwise the next ACL

NAL unit (3.6) in decoding order
3.4
atlas

collection of 2D bounding boxes and their associated information placed onto a rectangular frame and

corresponding to a volume in 3D space on which volumetric data is rendered
3.5
atlas bitstream

sequence of bits that forms the representation of atlas frames (3.8) and associated data forming one or

more CASs (3.36)
3.6
atlas coding layer NAL unit
ACL NAL unit

collective term for coded atlas tile layer NAL units (3.76) and the subset of NAL units (3.76) that have

reserved values of nal_unit_type that are classified as being of type class equal to ACL in this document

3.7
atlas coordinates

two scalars (x, y) with finite precision and dynamic range that indicate the location of an atlas sample

relative to the top left corner of an atlas frame, with x and y indicating the horizontal and vertical

direction, respectively
3.8
atlas frame

2D rectangular array of atlas samples onto which patches (3.85) are projected and additional

information related to the patches (3.85), corresponding to a volumetric frame (3.138)

3.9
atlas frame parameter set
AFPS

syntax structure (3.120) containing syntax elements (3.119) that apply to zero or more entire coded atlas

frames (3.8) as determined by the content of a syntax element (3.119) found in each tile header

2 © ISO/IEC 2021 – All rights reserved
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ISO/IEC 23090-5:2021(E)
3.10
atlas sample

position on the rectangular frame onto which patches (3.85) that are associated with an atlas (3.4) are

projected
3.11
atlas sequence
collection of atlas frames (3.8)
3.12
atlas sequence parameter set
ASPS

syntax structure (3.120) containing syntax elements (3.119) that apply to zero or more entire coded atlas

sequences (3.35) as determined by the content of a syntax element (3.119) found in the AFPS referred to

by a syntax element found in each tile header
3.13
atlas sub-bitstream

extracted sub-bitstream (3.108) from the V3C bitstream (3.128) containing a part of an atlas NAL

bitstream
3.14
atlas unit

set of NAL units (3.76) that contain all ACL NAL units (3.6) of a coded atlas (3.34) and their associated

non-ACL NAL units (3.2)
3.15
attribute

scalar or vector property optionally associated with each point in a volumetric frame (3.138) such as

colour, reflectance, surface normal, transparency, material ID, etc.
3.16
attribute access unit

collection of attribute maps (3.18) and auxiliary attribute frames, if available, for a specific attribute

(3.15) that correspond to the same time instance
3.17
attribute frame

2D rectangular array created through the aggregation of patches (3.85) containing values of a specific

attribute (3.15)
3.18
attribute map

attribute frame (3.17) containing attribute patch (3.85) information projected at a particular depth

indicated by the corresponding geometry map (3.59)
3.19
auxiliary attribute frame

2D rectangular array that is associated with RAW patches (3.103) and EOM patches (3.51), and contains

values of a specific attribute (3.15)
3.20
auxiliary geometry frame

2D rectangular array that is associated with RAW patches (3.103) and contains geometry (3.56) values

3.21
auxiliary video component

video component (3.125) indicated as being of auxiliary type through an appropriate flag in the VPS

(3.134) and containing data only associated with RAW patches (3.103) or EOM patches (3.51), or both

© ISO/IEC 2021 – All rights reserved 3
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ISO/IEC 23090-5:2021(E)
3.22
auxiliary video sub-bitstream

video sub-bitstream (3.127) indicated as being of auxiliary type through an appropriate flag in the VPS

(3.134) and containing data only associated with RAW patches (3.103) or EOM patches (3.51), or both

3.23
bitstream
ordered series of bits that forms the coded representation of the data
3.24
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
3.25
broken link access access unit
BLA access unit

access unit in which the coded atlas (3.34) with nal_layer_id equal to 0 is a BLA coded atlas (3.26)

3.26
broken link access coded atlas
BLA coded atlas

IRAP coded atlas (3.73) frame for which each ACL NAL unit (3.6) has nal_unit_type equal to NAL_BLA_W_

LP, NAL_GBLA_W_LP, NAL_BLA_W_RADL NAL_GBLA_W_RADL, NAL_BLA_N_LP or NAL_GBLA_N_LP.

Note 1 to entry: A BLA coded atlas does not use inter prediction in its decoding process, and could be the first

coded atlas in the bitstream in decoding order, or could appear later in the bitstream. Each BLA coded atlas

begins a new CAS, and has the same effect on the decoding process as an instantaneous decoding refresh (IDR)

coded atlas. However, a BLA coded atlas contains syntax elements that specify a non-empty DAB. When a BLA

coded atlas frame for which each ACL NAL un
...

FINAL
INTERNATIONAL ISO/IEC
DRAFT
STANDARD FDIS
23090-5
ISO/IEC JTC 1/SC 29
Information technology — Coded
Secretariat: JISC
representation of immersive media —
Voting begins on:
2021-02-10
Part 5:
Voting terminates on:
Visual Volumetric Video-based Coding
2021-04-07
(V3C) and Video-based Point Cloud
Compression (V-PCC)
Technologie de l'information — Représentation codée de média
immersifs —
Partie 5: Codage basé sur la vidéo volumétrique (V3C) et compression
de nuage de points basée sur la vidéo (V-PCC)
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/IEC FDIS 23090-5:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. ISO/IEC 2021
---------------------- Page: 1 ----------------------
ISO/IEC FDIS 23090-5:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2021

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. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO/IEC 2021 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/IEC FDIS 23090-5:2021(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

Introduction ................................................................................................................................................................................................................................vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Abbreviated terms ...........................................................................................................................................................................................15

5 Conventions ............................................................................................................................................................................................................16

5.1 General ........................................................................................................................................................................................................16

5.2 Arithmetic operators ......................................................................................................................................................................16

5.3 Logical operators ...............................................................................................................................................................................16

5.4 Relational operators ........................................................................................................................................................................17

5.5 Bit-wise operators.............................................................................................................................................................................17

5.6 Assignment operators ....................................................................................................................................................................18

5.7 Other operators ...................................................................................................................................................................................18

5.8 Mathematical functions ................................................................................................................................................................18

5.9 Order of operation precedence ..............................................................................................................................................19

5.10 Variables, syntax elements and tables .............................................................................................................................19

5.11 Text description of logical operations ..............................................................................................................................21

5.12 Processes ...................................................................................................................................................................................................22

6 Overall V3C characteristics, decoding operations and post-decoding processes ..........................23

6.1 V3C characteristics ...........................................................................................................................................................................23

6.2 V3C bitstream characteristics, decoding operations and post-decoding processes ................25

7 Bitstream format, partitioning and scanning processes .........................................................................................26

7.1 General ........................................................................................................................................................................................................26

7.2 V3C bitstream formats ..................................................................................................................................................................26

7.3 NAL bitstream formats ..................................................................................................................................................................27

7.4 Partitioning of atlas frames into tiles ...............................................................................................................................27

7.5 Tile partition scanning process .............................................................................................................................................28

8 Syntax and semantics ...................................................................................................................................................................................29

8.1 Method of specifying syntax in tabular form .............................................................................................................29

8.2 Specification of syntax functions and descriptors .................................................................................................30

8.3 Syntax in tabular form ...................................................................................................................................................................32

8.3.1 General...................................................................................................................................................................................32

8.3.2 V3C unit syntax ..............................................................................................................................................................33

8.3.3 Byte alignment syntax ..............................................................................................................................................34

8.3.4 V3C parameter set syntax .....................................................................................................................................35

8.3.5 NAL unit syntax ..............................................................................................................................................................38

8.3.6 Raw byte sequence payloads, trailing bits and byte alignment syntax ..........................38

8.3.7 Atlas tile data unit syntax ......................................................................................................................................44

8.3.8 Supplemental enhancement information message syntax.......................................................48

8.4 Semantics ..................................................................................................................................................................................................49

8.4.1 General...................................................................................................................................................................................49

8.4.2 V3C unit semantics......................................................................................................................................................49

8.4.3 Byte alignment semantics .....................................................................................................................................51

8.4.4 V3C parameter set semantics ............................................................................................................................51

8.4.5 NAL unit semantics .....................................................................................................................................................57

8.4.6 Raw byte sequence payloads, trailing bits and byte alignment semantics .................66

8.4.7 Atlas tile data unit semantics .............................................................................................................................79

8.4.8 Supplemental enhancement information message semantics ..............................................87

9 Decoding process ..............................................................................................................................................................................................87

9.1 General decoding process ...........................................................................................................................................................87

© ISO/IEC 2021 – All rights reserved iii
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ISO/IEC FDIS 23090-5:2021(E)

9.2 Atlas data decoding process .....................................................................................................................................................88

9.2.1 General atlas data decoding process ...........................................................................................................88

9.2.2 Decoding process for a coded atlas frame ..............................................................................................89

9.2.3 Atlas NAL unit decoding process ....................................................................................................................90

9.2.4 Atlas tile header decoding process ...............................................................................................................90

9.2.5 Decoding process for patch data units .......................................................................................................95

9.2.6 Decoding process of the block to patch map .....................................................................................110

9.2.7 Conversion of tile level patch information to atlas level patch information ..........111

9.3 Occupancy video decoding process ................................................................................................................................113

9.4 Geometry video decoding process ...................................................................................................................................114

9.5 Attribute video decoding process .....................................................................................................................................116

9.6 Sub-bitstream extraction process .....................................................................................................................................119

9.6.1 General................................................................................................................................................................................119

9.6.2 V3C unit extraction ..................................................................................................................................................119

9.6.3 NAL unit extraction process .............................................................................................................................120

10 Pre-reconstruction process ................................................................................................................................................................120

11 Reconstruction process ..........................................................................................................................................................................120

12 Post-reconstruction process .............................................................................................................................................................120

13 Adaptation process .....................................................................................................................................................................................120

14 Parsing process ...............................................................................................................................................................................................121

14.1 General .....................................................................................................................................................................................................121

14.2 Parsing process for 0-th order Exp-Golomb codes ............................................................................................121

14.2.1 General................................................................................................................................................................................121

14.2.2 Mapping process for signed Exp-Golomb codes .............................................................................122

Annex A (normative) Profiles, tiers and levels ...................................................................................................................................123

Annex B (normative) Post-decoding conversion to nominal video formats ........................................................137

Annex C (normative) V3C sample stream format .............................................................................................................................158

Annex D (normative) NAL sample stream format ............................................................................................................................160

Annex E (normative) Atlas hypothetical reference decoder .................................................................................................162

Annex F (normative) Supplemental enhancement information ......................................................................................179

Annex G (normative) Volumetric usability information ...........................................................................................................236

Annex H (normative) Video-based point cloud coding ..............................................................................................................247

Bibliography .........................................................................................................................................................................................................................331

iv © ISO/IEC 2021 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/IEC FDIS 23090-5:2021(E)
Foreword

ISO (the International Organization for Standardization) and IEC (the International Electrotechnical

Commission) form the specialized system for worldwide standardization. National bodies that

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The procedures used to develop this document and those intended for its further maintenance are

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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

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iso/ foreword .html.

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 23090 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

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ISO/IEC FDIS 23090-5:2021(E)
Introduction

Advances in 3D capturing and rendering technologies have unleashed a new wave of innovation in

virtual/augmented/mixed reality (VR/AR/MR) content creation and communication, of which visual

volumetric video is an integral part.

Visual volumetric video, a sequence of visual volumetric frames, if uncompressed, can be represented

by a large amount of data, which can be costly in terms of storage and transmission. This has led to the

need for a high coding efficiency standard for the compression of visual volumetric data.

Visual volumetric frames can be coded by converting the 3D volumetric information into a collection of

2D images and associated data. The converted 2D images can be coded using widely available video and

image coding specifications, such as ISO/IEC 14496-10 and ISO/IEC 23008-2 and the associated data

can be coded with mechanisms specified in this document. The coded images and the associated data

can then be decoded and used to reconstruct the 3D volumetric information. This document specifies

a generic mechanism for visual volumetric video coding, i.e. visual volumetric video-based coding. The

generic mechanism can be used by applications targeting volumetric content, such as point clouds,

immersive video with depth, mesh representations of visual volumetric frames, etc.

In addition to the generic mechanism of coding volumetric content, this document specifies one of the

applications of visual volumetric video-based coding targeting point cloud representations of visual

volumetric frames. In a point cloud sequence, each point cloud frame contains a collection of points.

Each point has a 3D position, i.e., geometry information, and each point can also be associated with a

number of attributes, such as colour, reflectance, surface normal, etc.

The International Organization for Standardization (ISO) and International Electrotechnical

Commission (IEC) draw attention to the fact that it is claimed that compliance with this document may

involve the use of a patent.

ISO and IEC take no position concerning the evidence, validity and scope of this patent right.

The holder of this patent right has assured ISO and IEC that he/she is willing to negotiate licences under

reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this

respect, the statement of the holder of this patent right is registered with ISO and IEC. Information may

be obtained from the patent database available at www .iso .org/ patents.

Attention is drawn to the possibility that some of the elements of this document may be the subject

of patent rights other than those in the patent database. ISO and IEC shall not be held responsible for

identifying any or all such patent rights.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/IEC FDIS 23090-5:2021(E)
Information technology — Coded representation of
immersive media —
Part 5:
Visual Volumetric Video-based Coding (V3C) and Video-
based Point Cloud Compression (V-PCC)
1 Scope

This document specifies the syntax, semantics and decoding for visual volumetric media using

video-based coding methods. This document also specifies processes that can be needed for

reconstruction of visual volumetric media, which can also include additional processes such as

post-decoding, pre-reconstruction, post-reconstruction and adaptation.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitute 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.

IEEE 754-2019, IEEE Standard for Floating-Point Arithmetic
IETF RFC 1321The MD5 Message-Digest Algorithm
IETF RFC 5646Tags for Identifying Languages
ISO/IEC 10646, Information technology — Universal Coded Character Set (UCS)

ISO/IEC 14496-10:2020, Information technology — Coding of audio-visual objects — Part 10: Advanced

Video Coding

ISO/IEC 14496-12, Information technology — Coding of audio-visual objects — Part 12: ISO base media

file format

ISO/IEC 14496-15, Information technology — Coding of audio-visual objects — Part 15: Carriage of

network abstraction layer (NAL) unit structured video in the ISO base media file format

ISO/IEC 23008-2:2020, Information technology — High efficiency coding and media delivery in

heterogeneous environments — Part 2: High efficiency video coding

ISO/IEC DIS 23090-3, Information technology — Coded representation of immersive media — Part 3:

Versatile video coding

ISO/IEC 23091-2, Coding-independent code points for video signal type identification

Rec. ITU-T T.35:2000, Procedure for the allocation of ITU-T defined codes for non standard facilities

Rec. ITU-T H.271:2006, Video back-channel messages for conveyance of status information and requests

from a video receiver to a video sender
1) Under preparation. Stage at time of publication: ISO/IEC DIS 23090-3:2020.
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ISO/IEC FDIS 23090-5:2021(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
3D bounding box

volume defined as a cuboid solid having six rectangular faces placed at right angles

3.2
associated non-ACL NAL unit

non-ACL NAL unit (3.78) that is associated with an ACL NAL unit (3.6) for the purpose of decoding or

other operations specified by this document
3.3
associated ACL NAL unit

preceding ACL NAL unit (3.6) in decoding order for a non-ACL NAL unit (3.78) with nal_unit_type equal

to NAL_EOS, NAL_EOB, NAL_FD, NAL_SUFFIX_NSEI, or NAL_SUFFIX_ESEI, or in the ranges of NAL_

RSV_NACL_48..NAL_RSV_NACL_52 or NAL_UNSPEC_53..NAL_UNSPEC_63; or otherwise the next ACL

NAL unit (3.6) in decoding order
3.4
atlas

collection of 2D bounding boxes and their associated information placed onto a rectangular frame and

corresponding to a volume in 3D space on which volumetric data is rendered
3.5
atlas bitstream

sequence of bits that forms the representation of atlas frames (3.8) and associated data forming one or

more CASs (3.36)
3.6
atlas coding layer NAL unit
ACL NAL unit

collective term for coded atlas tile layer NAL units (3.76) and the subset of NAL units (3.76) that have

reserved values of nal_unit_type that are classified as being of type class equal to ACL in this document

3.7
atlas coordinates

two scalars (x, y) with finite precision and dynamic range that indicate the location of an atlas sample

relative to the top left corner of an atlas frame, with x and y indicating the horizontal and vertical

direction, respectively
3.8
atlas frame

2D rectangular array of atlas samples onto which patches (3.85) are projected and additional

information related to the patches (3.85), corresponding to a volumetric frame (3.138)

3.9
atlas frame parameter set
AFPS

syntax structure (3.120) containing syntax elements (3.119) that apply to zero or more entire coded atlas

frames (3.8) as determined by the content of a syntax element (3.119) found in each tile header

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ISO/IEC FDIS 23090-5:2021(E)
3.10
atlas sample

position on the rectangular frame onto which patches (3.85) that are associated with an atlas (3.4) are

projected
3.11
atlas sequence
collection of atlas frames (3.8)
3.12
atlas sequence parameter set
ASPS

syntax structure (3.120) containing syntax elements (3.119) that apply to zero or more entire coded atlas

sequences (3.35) as determined by the content of a syntax element (3.119) found in the AFPS referred to

by a syntax element found in each tile header
3.13
atlas sub-bitstream

extracted sub-bitstream (3.108) from the V3C bitstream (3.128) containing a part of an atlas NAL

bitstream
3.14
atlas unit

set of NAL units (3.76) that contain all ACL NAL units (3.6) of a coded atlas (3.34) and their associated

non-ACL NAL units (3.2)
3.15
attribute

scalar or vector property optionally associated with each point in a volumetric frame (3.138) such as

colour, reflectance, surface normal, transparency, material ID, etc.
3.16
attribute access unit

collection of attribute maps (3.18) and auxiliary attribute frames, if available, for a specific attribute

(3.15) that correspond to the same time instance
3.17
attribute frame

2D rectangular array created through the aggregation of patches (3.85) containing values of a specific

attribute (3.15)
3.18
attribute map

attribute frame (3.17) containing attribute patch (3.85) information projected at a particular depth

indicated by the corresponding geometry map (3.59)
3.19
auxiliary attribute frame

2D rectangular array that is associated with RAW patches (3.103) and EOM patches (3.51), and contains

values of a specific attribute (3.15)
3.20
auxiliary geometry frame

2D rectangular array that is associated with RAW patches (3.103) and contains geometry (3.56) values

3.21
auxiliary video component

video component (3.125) indicated as being of auxiliary type through an appropriate flag in the VPS

(3.134) and containing data only associated with RAW patches (3.103) or EOM patches (3.51), or both

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ISO/IEC FDIS 23090-5:2021(E)
3.22
auxiliary video sub-bitstream

video sub-bitstream (3.127) indicated as being of auxiliary type through an appropriate flag in the VPS

(3.134) and containing data only associated with RAW patches (3.103) or EOM patches (3.51), or both

3.23
bitstream
ordered series of bits that forms the coded representation of the data
3.24
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
3.25
broken link access access unit
BLA access unit

access unit in which the coded atlas (3.34) with nal_layer_id equal to 0 is a BLA coded atlas (3

...

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