ISO/IEC 15444-9:2023

INTERNATIONAL ISO/IEC
STANDARD 15444-9
Second edition
2023-05
Information technology — JPEG 2000
image coding system —
Part 9:
Interactivity tools, APIs and protocols
Technologies de l'information — Système de codage d'images JPEG
2000 —
Partie 9: Outils d'interactivité, interfaces de programmes
d'application et protocoles
Reference number
© ISO/IEC 2023
© ISO/IEC 2023
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© ISO/IEC 2023 – All rights reserved

Foreword
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different types of document should be noted.
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
not 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.
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
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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 ITU-T (as ITU-T T.808) and drafted in accordance with its editorial rules,
in collaboration with Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee
SC 29, Coding of audio, picture, multimedia and hypermedia information.
This second edition cancels and replaces the first edition (ISO/IEC 15444-9:2005), which has been
technically revised. It also incorporates the Amendment(s) ISO/IEC 15444-9:2005/Amd 1:2006,
ISO/IEC 15444-9:2005/Amd 2:2008, ISO/IEC 15444-9:2005/Amd 3:2008, ISO/IEC 15444-9:2005/Amd
4:2010 and ISO/IEC 15444-9:2005/Amd 5:2014 and the Technical Corrigenda ISO/IEC 15444-
9:2005/Cor 1:2007, ISO/IEC 15444-9:2005/Cor 2:2008 and ISO/IEC 15444-9:2005/Cor 3:2011.
The main changes are as follows:
— extends support for the file format specified in Rec. ITU-T T.815 | ISO/IEC 15444-16;
— clarifies normative server responsibilities in response to certain request fields documented in
Annex C;
— removes the registration authority (Annex L); and
— adds media type registration information (Annex O).
A list of all parts in the ISO/IEC 15444 series can be found on the ISO and IEC websites.
© ISO/IEC 2023 – All rights reserved iii

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.
iv © ISO/IEC 2023 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 15444-9
RECOMMENDATION ITU-T T.808
Information technology – JPEG 2000 image coding system:
Interactivity tools, APIs and protocols
Summary
Rec. ITU-T T.808 | ISO/IEC 15444-9 provides a network protocol that allows for the interactive and progressive
transmission of JPEG 2000 coded data and files from a server to a client. The first edition of this Recommendation |
International Standard dates to 2005. It has since then been supplemented by amendments and corrigenda. Additionally,
other members of the JPEG 2000 family of Recommendations | International Standards, that are capable of being used
with the network protocol described in this Recommendation | International Standard have since been introduced. This
second edition incorporates the changes associated with these developments, without modifying the original scope.
This Recommendation was developed jointly with ISO/IEC JTC 1/SC 29/WG 1 (JPEG), and is common text with
ISO/IEC 15444-9.
This second edition cancels and replaces the first edition, which has been technically revised.
The main changes compared to the previous edition are as follows:
1. consolidates all outstanding amendments and corrigenda published since the first edition;
2. extends support for the file format specified in Rec. ITU-T T.815 | ISO/IEC 15444-16;
3. clarifies normative server responsibilities in response to certain request fields documented in Annex C;
4. removes the registration authority (Annex L); and
5. adds media type registration information (Annex O).
This Recommendation contains an electronic attachment that is available from the ITU website at:
https://handle.itu.int/11.1002/2000/7460, and from the ISO website at: https://standards.iso.org/iso-iec/15444/-9\ed-2/en.
History
*
Edition Recommendation Approval Study Group
Unique ID
1.0 ITU-T T.808 2005-01-08 16
11.1002/1000/7460
1.1 ITU-T T.808 (2005) Amd. 1 2006-05-29 16
11.1002/1000/8815
1.2 ITU-T T.808 (2005) Cor. 1 2007-01-13 16
11.1002/1000/9049
1.3 ITU-T T.808 (2005) Amd. 2 2007-08-29 16
11.1002/1000/9232
1.4 ITU-T T.808 (2005) Cor. 2 2008-06-13 16
11.1002/1000/9517
1.5 ITU-T T.808 (2005) Amd. 3 2008-06-13 16
11.1002/1000/9516
1.6 ITU-T T.808 (2005) Amd. 4 2010-05-22 16
11.1002/1000/10646
1.7 ITU-T T.808 (2005) Cor. 3 2011-05-14 16
11.1002/1000/11315
1.8 ITU-T T.808 (2005) Amd. 5 2013-03-16 16
11.1002/1000/11884
2.0 ITU-T T.808 (V2) 2022-12-14 16
11.1002/1000/15209
Keywords
API, application programme interface, image coding, interactivity, JPEG 2000, protocols.
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*
To access the Recommendation, type the URL http://handle.itu.int/ in the address field of your web browser, followed
by the Recommendation's unique ID. For example, http://handle.itu.int/11.1002/1000/11830-en.
© ISO/IEC 2023 – All rights reserved
Rec. ITU-T T.808 (12/2022) v
FOREWORD
The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of
telecommunications, information and communication technologies (ICTs). The ITU Telecommunication
Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical,
operating and tariff questions and issuing Recommendations on them with a view to standardizing
telecommunications on a worldwide basis.
The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes
the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics.
The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1.
In some areas of information technology which fall within ITU-T's purview, the necessary standards are
prepared on a collaborative basis with ISO and IEC.
NOTE
In this Recommendation, the expression "Administration" is used for conciseness to indicate both a
telecommunication administration and a recognized operating agency.
Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain
mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the
Recommendation is achieved when all of these mandatory provisions are met. The words "shall" or some other
obligatory language such as "must" and the negative equivalents are used to express requirements. The use of
such words does not suggest that compliance with the Recommendation is required of any party.
INTELLECTUAL PROPERTY RIGHTS
ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve
the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or
applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of
the Recommendation development process.
As of the date of approval of this Recommendation, ITU had not received notice of intellectual property,
protected by patents/software copyrights, which may be required to implement this Recommendation.
However, implementers are cautioned that this may not represent the latest information and are therefore
strongly urged to consult the appropriate ITU-T databases available via the ITU-T website at
http://www.itu.int/ITU-T/ipr/.
© ITU 2023
All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior
written permission of ITU.
vi Rec. ITU-T T.808 (12/2022)
© ISO/IEC 2023 – All rights reserved

CONTENTS
Page
1 Scope . 1
2 Normative references. 1
3 Definitions . 2
3.1 JPEG 2000 definitions . 2
3.2 HTTP definitions . 2
3.3 JPIP definitions . 2
3.4 Symbols . 4
4 Abbreviations . 6
5 Conventions . 6
5.1 ABNF rules . 6
5.2 File format ABNF rules. 7
5.3 Key to graphical descriptions of boxes (informative) . 7
6 General description . 8
6.1 JPIP protocol . 8
6.2 Purpose . 9
7 Conformance . 10
Annex A – The JPP-stream and JPT-stream media types . 11
A.1 Introduction . 11
A.2 Message header structure . 12
A.3 Data-bins . 14
A.4 Conventions for parsing and delivery of JPP-streams and JPT-streams . 22
A.5 Conventions for JPP-stream or JPT-stream interoperability (informative) . 22
Annex B – Sessions, channels, cache model and model-sets . 23
B.1 Requests within a session vs. stateless requests . 23
B.2 Channels and sessions . 23
B.3 Cache model management . 24
B.4 Interrogation and manipulation of model-sets . 24
Annex C – Client request . 25
C.1 Request syntax . 25
C.2 Target identification fields . 26
C.3 Fields for working with sessions and channels . 28
C.4 View-window request fields . 29
C.5 Metadata request fields. 42
C.6 Data limiting request fields . 48
C.7 Server control request fields . 48
C.8 Cache management request fields . 52
C.9 Upload request parameters . 57
C.10 Client capability and preference request fields. 57
Annex D – Server response signalling . 65
D.1 Reply syntax . 65
D.2 JPIP response headers . 67
D.3 Response data . 72
Annex E – Uploading images to the server . 73
E.1 Introduction . 73
E.2 Upload request . 73
E.3 Server response . 73
E.4 Merging data on the server . 74
Annex F – Using JPIP over HTTP . 76
F.1 Introduction . 76
F.2 Requests . 76
F.3 Session establishment . 77
Rec. ITU-T T.808 (12/2022) vii
© ISO/IEC 2023 – All rights reserved

F.4 Responses . 77
F.5 Additional HTTP features . 78
F.6 HTTP and length request field (informative) . 79
Annex G – Using JPIP with HTTP requests and TCP returns . 80
G.1 Introduction . 80
G.2 Client requests . 80
G.3 Session establishment . 80
G.4 Server responses . 81
G.5 TCP and length request field (informative) . 81
Annex H – Using JPIP with alternate transports . 82
H.1 Introduction . 82
H.2 Reliable requests with unreliable data . 82
H.3 Unreliable requests with unreliable data . 83
H.4 Request and response syntax . 83
H.5 Session establishment . 84
Annex I – Indexing JPEG 2000 files for JPIP . 85
I.1 Introduction (informative) . 85
I.2 Identifying the use of JPIP index boxes in the JPEG 2000 file format compatibility list . 86
I.3 Defined boxes. 86
I.4 Association of codestream indexes with codestreams . 94
I.5 Placement restrictions (informative) . 94
Annex J – Profiles and variants for interoperability and testing . 95
J.1 Introduction . 95
J.2 Definition of variants . 95
J.3 Definition of profiles . 96
J.4 Testing methodology . 98
Annex K – Using JPIP with HTTP requests and UDP returns . 103
K.1 Introduction . 103
K.2 Client requests . 103
K.3 Response data delivery and channel establishment . 103
K.4 Server responses . 104
K.5 Framing of response data into chunks . 104
K.6 Client acknowledgement of server responses . 105
K.7 UDP and Maximum Response Length Field (informative) . 106
K.8 Implementation strategies for acknowledged communication (informative) . 106
K.9 Implementation strategies for unacknowledged communication (informative) . 106
Annex L – Registration of extensions . 108
Annex M – Application examples . 109
M.1 Introduction . 109
M.2 Use of JPIP with codestreams in other file formats . 109
M.3 Tile-part implementation techniques . 109
M.4 Precinct-based implementation techniques . 110
M.5 JPIP protocol transcripts . 111
M.6 Using JPIP with HTML. 114
Annex N – JPIP ABNF collection . 115
N.1 JPIP Request ABNF . 115
N.2 JPIP Response BNF . 122
Annex O – Media type specifications and registrations. 126
O.1 General . 126
O.2 JPP-stream . 126
O.3 JPT-stream . 127
Bibliography . 128
xiii Rec. ITU-T T.808 (12/2022)
© ISO/IEC 2023 – All rights reserved

Figures
Page
Figure 1 – Example of the box description figures . 8
Figure 2 – Example of the superbox description figures . 8
Figure 3 – JPIP protocol overview . 8
Figure 4 – JPIP protocol stack . 9
Figure A.1 – Examples of a JPEG 2000 file, JPIP data-bins and JPIP-stream relationships (after G.J. Colyer
and R.A. Clark, IEEE Trans. Consumer Electronics, 49 (2003), pp. 850–854) . 11
Figure A.2 – VBAS structure . 12
Figure A.3 – Bin-ID VBAS structure . 12
Figure A.4 – Example precinct data-bin . 15
Figure A.5 – Metadata-bin example colour scheme . 16
Figure A.6 – A sample JP2 file . 17
Figure A.7 – A sample JP2 file divided into three metadata-bins. 17
Figure A.8 – A superbox with a referenced metadata-bin . 18
Figure A.9 – An invalid division of the file into metadata-bins . 18
Figure A.10 – Example of the use of stream equivalents . 19
Figure A.11 – Placeholder box structure . 20
Figure C.1 –Desired region within an image . 30
Figure C.2 – Desired region with respect to the subsampled reference grid . 30
Figure C.3 – Colourspace specification box selection procedure . 61
Figure G.1 – Response data structure on http-tcp connection . 81
Figure I.1 – Part of an example JPEG 2000 file containing JPIP index boxes . 86
Figure I.2 – Organization of the contents of a Codestream Index box . 87
Figure I.3 – Organization of the contents of a Codestream Finder box . 88
Figure I.4 – Organization of the contents of a Manifest box . 88
Figure I.5 – Organization of the contents of a Fragment Array Index box . 89
Figure I.6 – Organization of the contents of a Header Index Table box . 90
Figure I.7 – Organization of the contents of a Tile-part Index Table box . 91
Figure I.8 – Organization of the contents of a Tile Header Index Table box . 91
Figure I.9 – Organization of the contents of a Precinct Packet Index Table box . 91
Figure I.10 – Organization of the contents of a Packet Header Index Table box . 92
Figure I.11 – Organization of the contents of a File Index box . 92
Figure I.12 – Organization of the contents of a File Finder box . 93
Figure I.13 – Organization of the contents of a Proxy box . 93
Figure I.14 – Organization of the contents of an Index Finder box . 94
Figure K.1 – Response data structure on http-udp connection . 104
Rec. ITU-T T.808 (12/2022) ix
© ISO/IEC 2023 – All rights reserved

Tables
Page
Table A.1 – Bin-ID additional VBAS indication . 13
Table A.2 – Class identifiers for different data-bin message classes . 13
Table A.3 – Valid values for the Flags field of a Placeholder box . 21
Table C.1 – Round direction options . 33
Table C.2 – Metadata request qualifier flags . 47
Table C.3 – Alignment boundaries based on bin type . 49
Table C.4 – Valid image return types . 49
Table C.5 – Cache descriptor option summary . 55
Table C.6 – Valid capabilities of the processing-capabilities element . 58
Table C.7 – Valid values of the config-capability parameter . 58
Table C.8 – View-window handling preferences . 60
Table C.9 – Colourspace method client preferences . 60
Table C.10 – Placeholder preferences . 62
Table C.11 – Codestream sequencing preferences . 63
Table C.12 – Conciseness preferences. 63
Table D.1 – Valid values of transport-param . 67
Table D.2 – Defined reason codes . 72
Table D.3 – Additional handled-req-option values for particular request fields . 72
Table I.1 – Defined boxes (Informative) . 87
Table I.2 – Container type values . 88
Table I.3 – Version values . 90
Table J.1 – Defining requirements of variants . 96
Table J.2 – Set of fields included in each profile . 97
Table K.1 – Interpretation of the "control" field in each data chunk header. 105
Table M.1 – Example of the use of auxiliary fields in a simple case . 110
Table M.2 – Example of the use of auxiliary fields in a more complicated case . 110
x Rec. ITU-T T.808 (12/2022)
© ISO/IEC 2023 – All rights reserved

Introduction
Rec. ITU-T T.800 | ISO/IEC 15444-1 (JPEG 2000) is a specification that describes an image compression system that
allows great flexibility, not only for the compression of images but also for access into the codestream. The codestream
provides a number of mechanisms for locating and extracting portions of the compressed image data for the purpose of
retransmission, storage, display, or editing. This access allows storage and retrieval of compressed image data appropriate
for a given application without decoding.
The purpose of this Recommendation | International Standard is to provide a network protocol that allows for the
interactive and progressive transmission of JPEG 2000 coded data and files from a server to a client. This protocol allows
a client to request only the portions of an image (by region, quality or resolution level) that are applicable to the client's
needs. The protocol also allows the client to access metadata or other content from the file.
The substantive updates in this edition, compared to Edition 1, are:
1. consolidates all outstanding amendments and corrigenda published since the first edition;
2. extends support the file format specified in Rec. ITU-T T.815 | ISO/IEC 15444-16;
3. clarifies normative server responsibilities in response to certain request fields documented in Annex C;
4. removes the registration authority (Annex L); and
5. adds media type registration information (Annex O).
Rec. ITU-T T.808 (12/2022) xi
© ISO/IEC 2023 – All rights reserved

INTERNATIONAL STANDARD
ITU-T RECOMMENDATION
Information technology – JPEG 2000 image coding system:
Interactivity tools, APIs and protocols
1 Scope
This Recommendation | International Standard defines, in an extensible manner, syntaxes and methods for the remote
interrogation and optional modification of JPEG 2000 codestreams and files in accordance with their definition in Rec.
ITU-T T.800 | ISO/IEC 15444-1 and other members of the Rec. ITU-T T.8xx | ISO/IEC 15444-x family of
Recommendations | Standards.
In this Recommendation | International Standard, the defined syntaxes and methods are referred to as the JPEG 2000
Interactive Protocol, "JPIP", and interactive applications using JPIP are referred to as "JPIP systems."
JPIP specifies a protocol consisting of a structured series of interactions between a client and a server by means of which
image file metadata, structure and partial or whole image codestreams can be exchanged in a manner that avoids or
minimises the communication of information not required by client. This Recommendation | International Standard
includes definitions of the semantics and values to be exchanged, and suggests how these can be passed using a variety
of existing network transports.
With JPIP, the following tasks can be accomplished in varying, compatible ways:
– the exchange of capabilities;
– the negotiation of capabilities to use in a session;
– the request and transfer of the following elements from a variety of containers, such as JPEG 2000 files,
JPEG 2000 codestreams and other container files:
• selective data segments;
• selective and defined structures;
• parts of an image or its related metadata.
2 Normative references
The following Recommendations and International Standards contain provisions which, through reference in this text,
constitute provisions 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.
– Recommendation ITU-T T.800 | ISO/IEC 15444-1, Information technology – JPEG 2000 image coding
system: Core coding system.
– Recommendation ITU-T T.801 | ISO/IEC 15444-2, Information technology – JPEG 2000 image coding
system: Extensions.
– Recommendation ITU-T T.802 | ISO/IEC 15444-3, Information technology – JPEG 2000 image coding
system: Motion JPEG 2000.
– Recommendation ITU-T T.805 | ISO/IEC 15444-6, Information technology – JPEG 2000 image coding
system: Compound image file format.
– Recommendation ITU-T T.809 | ISO/IEC 15444-10, Information technology – JPEG 2000 image coding
system: Extensions for three-dimensional data.
– Recommendation ITU-T T.814 | ISO/IEC 15444-15, Information technology – High-Throughput JPEG
2000.
– Recommendation ITU-T T.815 | ISO/IEC 15444-16, Information technology – Encapsulation of JPEG
2000 images into ISO/IEC 23008-12.
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This Recommendation | International Standard contains an electronic attachment that is available from the ITU website
at: https://handle.itu.int/11.1002/2000/7460, and from the ISO website at: https://standards.iso.org/iso-iec/15444/-
9\ed-2/en.
Rec. ITU-T T.808 (12/2022) 1
© ISO/IEC 2023 – All rights reserved

– IETF RFC 768 (1980), User Datagram Protocol. Available from World Wide Web:
http://www.ietf.org/rfc/rfc0768.txt.
– IETF RFC 2046 (1996), Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types.
Available from World Wide Web: http://www.ietf.org/rfc/rfc2046.txt.
– IETF RFC 2616 (1999), Hypertext Transfer Protocol – HTTP/1.1. Available from World Wide Web:
http://www.ietf.org/rfc/rfc2616.txt.
– IETF RFC 3986 (2005), Uniform Resource Identifiers (URI): Generic Syntax. Available from World Wide
Web: https://datatracker.ietf.org/doc/html/rfc3986.
– IETF RFC 5234 (2008), Augmented BNF for Syntax Specifications: ABNF. Available from World Wide
Web: https://datatracker.ietf.org/doc/html/rfc5234.
– IETF RFC 9293 (2022), Transmission Control Protocol. Available from World Wide Web:
https://datatracker.ietf.org/doc/html/rfc9293.
3 Definitions
For the purposes of this Recommendation | International Standard, the terms and definitions given in Rec. ITU-T T.800 |
ISO/IEC 15444-1 and Rec. ITU-T T.801 | ISO/IEC 15444-2 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 JPEG 2000 definitions
The following definitions are used within this Recommendation | International Standard. In some cases, these definitions
differ from those used in other standards and/or Recommendations.
3.1.1 J2KI: A file that conforms to the ‘j2ki’ brand specified in Rec. ITU-T T.815 | ISO/IEC 15444-16.
3.1.2 J2KS: A file that conforms to the ‘j2ks’ brand specified in Rec. ITU-T T.815 | ISO/IEC 15444-16.
3.1.3 JPH: The file format specified in Rec. ITU-T T.814 | ISO/IEC 15444-15: High Throughput JPEG 2000.
3.1.4 JPEG 2000 codestream: Codestream conforming to the specification in Rec. ITU-T. T.800 | ISO/IEC 15444-1,
possibly including capabilities specified elsewhere.
3.1.5 JPEG 2000 family file: File conforming to one of the file formats defined in the Rec. ITU-T T.8xx | ISO/IEC
15444-x family of Recommendations | Standards.
3.1.6 JPM: The file format specified in Rec. ITU-T T.805 | ISO/IEC 15444-6.
3.1.7 metadata: Any collection of "boxes" from a JPEG 2000 family file.
3.1.8 MJ2: The file format specified in Rec. ITU-T T.802 | ISO/IEC 15444-3.
3.2 HTTP definitions
The following definitions are intended to match HTTP/1.1. In the case of any difference, these definitions shall be used.
3.2.1 connection: Transport layer virtual circuit established between two programs for the purpose of
communication.
3.2.2 entity: The information transferred as the payload of a request or response.
Note on entry: An entity consists of metainformation in the form of entity-header fields and content in the form of an entity-body.
3.2.3 proxy: An intermediary program which acts as both a server and a client for the purpose of making requests on
behalf of other clients.
Note on entry: Requests are serviced internally or by passing them on, with possible translation, to other servers.
3.3 JPIP definitions
The following definitions are used within this Recommendation | International Standard. In some cases, these definitions
differ from those used in other standards and/or Recommendations.
2 Rec. ITU-T T.808 (12/2022)
© ISO/IEC 2023 – All rights reserved

3.3.1 cache (client-side): Cache managed by the Client for storing JPIP data-bins.
Note on entry: The Client might have a limited cache and might have to purge cached JPIP data-bins from time to time.
3.3.2 cacheable response: Response that may be stored within a cache for use in answering subsequent requests.
Note on entry: Even if a resource is cacheable, there might be additional constraints on whether a cache can use the cached copy
for a particular request.
3.3.3 cache-model (server-side): Server-side estimation of the data-bins or portions of data-bins that are available
in the client's cache.
Note on entry: The server can add items to its estimation of the client's cache because it assumes successfully delivery, or because
it has received acknowledgements of transmitted data, or because of cache-model
...