ISO/IEC 15444-4:2024

International
Standard
ISO/IEC 15444-4
Information technology — JPEG
Fourth edition
2000 image coding system —
2024-05
Part 4:
Conformance testing
Technologies de l'information — Système de codage d'images
JPEG 2000 —
Partie 4: Tests de conformité
Reference number
© ISO/IEC 2024
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
© ISO/IEC 2024 – All rights reserved
ii
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.
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.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www.iso.org/iso/foreword.html.
In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by ITU-T (as ITU-T Rec T.803) 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 fourth edition cancels and replaces the third edition (ISO/IEC 15444-4:2021), which has been technically
revised.
The main changes are as follows:
— the maximum allowable errors associated with compliance Class 1, for both Rec. ITU-T T.800 | ISO/IEC
15444-1 and Rec. ITU-T T.814 | ISO/IEC 15444-15 codestreams, have been relaxed in a few cases to
ensure that well designed 16-bit fixed-point implementations of the inverse discrete wavelet transform
should be able to pass all compliance tests for Class 1;
— two additional test codestreams have been added along with conformance bounds, to facilitate testing of
inverse wavelet and component decorrelating transform accuracy;
— a number of codestreams and files conforming to Rec. ITU-T T.801 | ISO/IEC 15444-2 have been included
for informative purposes only, to facilitate the development of decoders and file format readers that are
able to support features beyond the core capabilities found in Rec. ITU-T T.800 | ISO/IEC 15444-1 and
Rec. ITU-T T.814 | ISO/IEC 15444-15.
A list of all parts in the ISO/IEC 15444 series can be found on the ISO and IEC websites.
© ISO/IEC 2024 – 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.
© ISO/IEC 2024 – All rights reserved
iv
CONTENTS
Page
1 Scope . 1
2 References . 1
3 Definitions . 1
4 Abbreviations and symbols . 4
4.1 Abbreviations . 4
4.2 Symbols . 5
5 Conventions . 6
6 General description . 6
6.1 Profiles, derived sets and compliance classes . 7
6.2 Decoders . 8
6.3 Encoders and codestreams . 8
6.4 Implementation compliance statement . 8
6.5 Abstract test suites . 8
6.6 Encoder compliance testing procedure . 9
6.7 Decoder compliance testing procedure . 9
6.8 Procedures for testing file format readers . 9
6.9 Additional test codestreams and files . 9
7 Copyright . 9
8 Compliance files availability and updates . 9
Annex A Decoder compliance classes . 10
A.1 Compliance class parameter definitions . 10
A.1.1 Profile: codestream guarantees . 10
A.1.2 H, W, C: Image size guarantees . 10
A.1.3 N : Code-block parsing guarantee . 11
cb
A.1.4 N : Component parsing guarantee . 11
comp
A.1.5 L : Coded data buffering guarantee . 11
body
A.1.6 M: Decoded bit-plane guarantee . 12
A.1.7 P: 9-7I precision guarantee . 12
A.1.8 B: 5-3R precision guarantee . 12
A.1.9 T : Transform level guarantee . 12
L
A.1.10 L: Layer guarantee. 12
A.1.11 Progressions . 12
A.1.12 Tile-parts . 12
A.1.13 Precincts . 13
A.1.14 M : Magnitude bound guarantee . 13
MAGB
A.2 Compliance class definitions . 13
A.3 Lossless encoding and decoding . 14
Annex B Decoder compliance testing procedures . 15
B.1 General . 15
B.2 Decoder test procedure . 15
B.2.1 Files for testing . 16
B.2.2 Decoder settings . 16
B.2.3 Output file format conversion . 16
B.2.4 Compare decoded and formatted components with reference components . 18
B.2.5 Compare error metrics with specification . 18
B.2.6 Reference components file format . 18
Annex C Compliance tests . 20
C.1 Abstract test suite (informative) . 20
C.1.1 Syntax and compressed data order . 20
C.1.2 Arithmetic entropy encoding . 20
C.1.3 Coefficient bit modelling . 21
C.1.4 Quantization . 21
C.1.5 Discrete wavelet transform. 21
C.1.6 DC level shift and multiple component transform . 21
Rec. ITU-T T.803 (V3) (02/2024) v
© ISO/IEC 2024 – All rights reserved

C.1.7 Region of interest . 21
C.1.8 JP2 file format . 21
C.1.9 High throughput cleanup pass coding . 22
C.1.10 HT refinement pass coding . 22
C.1.11 Placeholder passes . 22
C.1.12 Mixing of HT and J2K code-blocks within HTJ2K codestreams . 22
C.1.13 JPH File format . 22
C.2 Executable test suite . 22
C.2.1 Class 0 Profile-0 . 23
C.2.2 Class 0 Profile-1 . 27
C.2.3 Class 1 Profile-0 . 28
C.2.4 Class 1 Profile-1 . 30
C.2.5 Class 1HF Profile 1 . 30
Annex D Encoder compliance test procedure . 32
D.1 General . 32
D.2 Reference decoder . 32
D.3 Compliance requirement and acceptance . 32
D.4 Encoding compliance test procedure . 32
Annex E Decoder implementation compliance statement . 34
E.1 General . 34
E.2 Decoder implementation compliance statement . 34
E.3 Extended support . 34
Annex F Encoder implementation compliance statement . 37
F.1 General . 37
F.2 Encoder description . 37
Annex G JP2 and JPH file format reader compliance testing procedures. 39
G.1 General . 39
G.2 JP2 file compliance requirement and acceptance . 39
G.3 Reading a JP2 file compliance test procedure . 39
G.4 JP2 file format test codestreams and images . 40
G.4.1 Test files . 40
G.4.2 Reference decoded images . 40
G.4.3 Tolerances . 40
G.4.4 Additional information regarding the JP2 test files . 41
G.5 JPH file format test codestreams and images . 42
G.5.1 Test files . 42
G.5.2 Relationship between the JP2 and JPH test files . 42
Annex H Test codestreams and files conforming to Rec. ITU-T T.801 | ISO/IEC 15444-2 . 43
H.1 General . 43
H.2 Extended test codestreams . 43
H.3 JPX test files . 44
Bibliography . 45
Electronic attachment: Codestreams used in the application of the procedures described in this Specification.
List of Tables
Page
Table 1 – HTJ2K derived sets employed in this Recommendation | International Standard . 8
Table A.1 – Definitions of compliance classes (Cclass) for J2K decoders . 13
Table A.2 – Definitions of derived compliance classes (Cclass) for HTJ2K decoders . 13
Table A.3 – Definitions of HiFi compliance classes . 14
Table C.1 – Class 0 Profile-0 reference images and allowable errors . 23
Table C.1bis – Additional allowable errors for HTJ2K TCSs belonging to derived set 0 . 24
Table C.2 – Items tested by Profile-0 codestreams . 24
Table C.2bis – Items tested by derived set 0 HTJ2K codestreams . 25
vi Rec. ITU-T T.803 (V3) (02/2024)
© ISO/IEC 2024 – All rights reserved

Table C.3 – Profile-0 codestream 0 contents . 26
Table C.4 – Class 0 Profile-1 reference images and allowable errors . 27
Table C.4bis – Additional allowable errors for HTJ2K TCSs belonging to derived set 1 . 27
Table C.5 – Items tested by Profile-1 codestreams . 28
Table C.5bis – Items tested by derived set 1 HTJ2K codestreams . 28
Table C.6 – Class 1 Profile-0 reference files and maximum error . 29
Table C.7 – Class 1 Profile-1 reference images and allowable error . 30
Table C.8 – Class 1HF Profile 1 reference images and allowable error . 31
Table E.1 – ICS for defined Cclasses, profiles and derived sets . 34
Table E.2 – Extended capabilities for Cclass 0 . 35
Table E.3 – Extended capabilities for Cclass 1 . 35
Table E.4 – Extended capabilities for Cclass 2 . 35
Table E.5 – Extended capabilities for derived Cclass 0h . 36
Table E.6 – Extended capabilities for derived Cclass 1h . 36
Table E.7 – Extended capabilities for derived Cclass 2h . 36
Table F.1 – Encoder implementation marker usage . 37
Table G.1 – JP2 reference images and allowable error . 41
Table H.1 – Properties of each extended codestream . 43
Table H.2 – Properties of each JPX test file . 44
List of Figures
Figure B.1 – Decoder compliance test flow chart . 15
Figure D.1 – Encoder compliance test block diagram . 33
Figure G.1 – JP2 file format reader compliance test block diagram . 40
Rec. ITU-T T.803 (V3) (02/2024) vii
© ISO/IEC 2024 – All rights reserved

© ISO/IEC 2024 – All rights reserved

INTERNATIONAL STANDARD
ITU-T RECOMMENDATION
Information technology – JPEG 2000 image coding system:
Conformance testing
1 Scope
This Recommendation | International Standard specifies the framework, concepts, methodology for testing, and criteria
to be achieved to claim compliance to Rec. ITU-T T.800 | ISO/IEC 15444-1 or Rec. ITU-T T.814 | ISO/IEC 15444-15. It
provides a framework for specifying abstract test suites (ATSs) and for defining the procedures to be followed during
compliance testing.
This Recommendation | International Standard:
‒ specifies compliance testing procedures for encoding and decoding using Rec. ITU-T T.800 |
ISO/IEC 15444-1 and Rec. ITU-T T.814 | ISO/IEC 15444-15;
‒ specifies codestreams, decoded images, and error metrics to be used with the testing procedures;
‒ specifies ATSs;
‒ provides guidance for creating an encoder compliance test
This Recommendation | International Standard does not include the following tests:
Acceptance testing: the process of determining whether an implementation satisfies acceptance criteria and enables the
user to determine whether or not to accept the implementation. This includes the planning and execution of several kinds
of tests (e.g., functionality, quality, and speed performance testing) that demonstrate that the implementation satisfies the
user requirements.
Performance testing: measures the performance characteristics of an implementation under test (IUT) such as its
throughput and responsiveness, under various conditions.
Robustness testing: the process of determining how well an implementation processes data which contains errors.
2 References
The following Recommendations and International Standards contain provisions which, through reference in this text,
constitute provisions of this Recommendation | International Standard. At the time of publication, the editions indicated
were valid. All Recommendations and Standards are subject to revision, and parties to agreements based on this
Recommendation | International Standard are encouraged to investigate the possibility of applying the most recent edition
of the Recommendations and Standards listed below. Members of IEC and ISO maintain registers of currently valid
International Standards. The Telecommunication Standardization Bureau of the ITU maintains a list of currently valid
ITU-T Recommendations.
– Recommendation ITU-T T.800 | ISO/IEC 15444-1, Information technology – JPEG 2000 image coding
system: Core coding system.
– Recommendation ITU-T T.814 | ISO/IEC 15444-15, Information technology – JPEG 2000 image coding
system: High-throughput JPEG 2000.
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, Rec. ITU-T T.814 | ISO/IEC 15444-15 and the following apply.
3.1 abstract test suite (ATS): Generic compliance testing concepts and procedures for a given requirement.
3.2 arithmetic coder: Entropy coder that converts variable length strings to variable length codes (encoding) and
vice versa (decoding).
____________________
This Recommendation | International Standard includes an electronic attachment with the codestreams used in the application of
the procedures described the Specification.
Rec. ITU-T T.803 (V3) (02/2024) 1
© ISO/IEC 2024 – All rights reserved

3.3 big endian: Order of bytes in which the most significant byte comes first.
3.4 bit: Contraction of the term "binary digit"; a unit of information represented by a 0 or a 1.
3.5 bit-depth: Number of bits required to represent an original component of an image:
3.6 bit-plane: Two-dimensional array of bits, referring to all the bits of the same magnitude in all coefficients or
samples, within a component, a tile- component, a code-block, a region of interest, or other.
3.7 bitstream: Sequence of bits resulting from the coding of a sequence of symbols, not including any markers or
marker segments from the main and tile-part headers, not including packet headers, and not including in stream markers
or marker segments or the end of codestream marker.
3.8 box: Portion of the file format defined by a length and unique box type.
Note on entry: Boxes of some types may contain other boxes.
3.9 byte: Eight bits.
3.10 Cclass: Defines a level of performance for a decoder, also providing guidance for encoders to produce
codestreams that are easily decodable by compliant decoders.
3.11 code-block: A rectangular grouping of coefficients from the same sub-band of a tile-component.
3.12 coder: Embodiment of either an encoding or decoding process.
3.13 codestream: Collection of one or more bitstreams and the main header, tile-part headers, and the end of
codestream marker required for their decoding and expansion into image data.
Note on entry: This is the image data in a compressed form with all of the signalling needed to decode, but not including the file
format.
3.14 coding pass: Procedure accessing coefficients in a code-block where the context and bit are determined.
Note on entry: Typically, there are three different coding passes for each bit-plane, each coefficient will be represented in exactly
one of the three passes; for an encoder a coding pass examines coefficients and augments a bitstream; for a decoder a coding pass
reads a bitstream and updates coefficients.
3.15 coefficient: Value that result from a transformation.
3.16 component: Two-dimensional array of samples.
Note on entry: An image typically consists of several components (e.g., red, green, and blue).
3.17 compressed image data: Part or all of a codestream, or a collection of bitstreams in part or all of a codestream.
3.18 compliance: Fulfilment of the specified requirements, as defined in this Recommendation | International
Standard, for a given Profile and Cclass.
3.19 compliance test procedure: The process of assessing compliance.
3.20 context: Function of coefficients previously decoded and used to condition the decoding of the present
coefficient.
3.21 decoder: Embodiment of a decoding process, and optionally a colour transformation process.
3.22 decoding process: Process that takes as its input all or part of a codestream and outputs all or part of a
reconstructed image.
3.23 decomposition level: Collection of wavelet sub-bands where each coefficient has the same spatial impact or
span with respect to the source component samples, including all sub-bands of the same two-dimensional sub-band
decomposition, where the last decomposition level also includes the LL sub-band.
3.24 discrete wavelet transformation (DWT): Transformation that iteratively transforms one signal into two or
more filtered and decimated signals corresponding to different frequency bands.
Note on entry: This transformation operates on spatially discrete samples.
3.25 encoder: Embodiment of an encoding process, optionally including a colour transformation process.
3.26 encoding process: Process that takes as its input all or part of a source image data and outputs a codestream.
3.27 executable test suite (ETS): Set of executable test cases that support the abstract test cases.
3.28 file format: Codestream and additional support data and information not explicitly required for the decoding
of the codestream.
2 Rec. ITU-T T.803 (V3) (02/2024)
© ISO/IEC 2024 – All rights reserved

Note on entry: Examples of such support data include text fields providing titling, security and historical information, data to
support placement of multiple codestreams within a given data file, and data to support exchange between platforms or conversion
to other file formats.
3.29 fully decode: Applying Rec. ITU-T T.800 | ISO/IEC 15444-1 to produce an image from a codestream where
all coded data in the codestream has been used to produce the image.
3.30 guard bits: Additional most significant bitplanes, beyond the nominal dynamic range of a wavelet sub-band,
that have been included in coding of the sample data.
3.31 header: Either a part of the codestream that contains only markers and marker segments (main header and tile
part header) or the signalling part of a packet (packet header).
3.32 image: Set of all components.
3.33 image data: Component samples making up an image.
Note on entry: Image data can refer to either the source image data or the reconstructed image data.
3.34 implementation: Realization of a specification.
3.35 implementation compliance statement (ICS): Statement of specification options and the extent to which they
have been implemented by an implementation under test.
3.36 implementation under test (IUT): Implementation that is being evaluated for compliance.
3.37 irreversible: Transformation, progression, system, quantization, or other process that, due to systemic or
quantization error, prevents lossless recovery.
3.38 JPEG (Joint Photographic Experts Group): The joint ISO/ITU committee responsible for developing
standards for continuous-tone still picture coding, also referring to the standards produced by this committee: Rec. ITU-T
T.81 | ISO/IEC 10918-1, Rec. ITU-T T.83 | ISO/IEC 10918-2, Rec. ITU-T T.84 | ISO/IEC 10918-3 and Rec. ITU-T T.87
| ISO/IEC 14495-1.
3.39 LL sub-band: Sub-band obtained by forward horizontal low-pass filtering and vertical low-pass filtering.
Note on entry: This sub-band contributes to reconstruction with inverse vertical low-pass filtering and horizontal low-pass filtering.
3.40 layer: Collection of compressed image data from coding passes of one, or more, code-blocks of a tile-
component, where layers have an order for encoding and decoding that has to be preserved.
3.41 lossless: Descriptive term for the effect of the overall encoding and decoding processes in which the output of
the decoding process is identical to the input to the encoding process, such that distortion-free restoration can be assured
and all of the coding processes or steps used for encoding and decoding are reversible.
3.42 lossy: Descriptive term for the effect of the overall encoding and decoding processes in which the output of the
decoding process is not identical to the input to the encoding process, because at least one of the coding processes or steps
used for encoding and decoding is irreversible.
3.43 main header: Group of markers and marker segments at the beginning of the codestream that describe the
image parameters and coding parameters that can apply to every tile and tile-component.
3.44 marker: Two-byte code in which the first byte is hexadecimal FF (0xFF) and the second byte is a value between
1 (0x01) and hexadecimal FE (0xFE).
3.45 marker segment: Marker and associated (not empty) set of parameters.
3.46 packet: Part of the codestream comprising a packet header and the compressed image data from one layer of
one precinct of one resolution level of one tile-component.
3.47 packet header: Portion of the packet that contains signalling necessary for decoding that packet.
3.48 parser: Reads and identifies components of the codestream down to the code-block level.
3.49 partial decoding: Producing an image from a subset of an entire codestream.
3.50 precinct: Rectangular region of a transformed tile-component, within each resolution level, used for limiting
the size of packets.
3.51 precision: Number of bits allocated to a particular sample, coefficient, or other binary numerical representation.
3.52 progression: Order of a codestream where the decoding of each successive bit contributes to a "better"
reconstruction of the image.
Note on entry: What metrics make the reconstruction "better" is a function of the application; some examples of progression are
increasing resolution or improved sample fidelity.
Rec. ITU-T T.803 (V3) (02/2024) 3
© ISO/IEC 2024 – All rights reserved

3.53 profile: Subset of technology, from Rec. ITU-T T.800 | ISO/IEC 15444-1, that meets the needs of a given
application with limits on parameters within a selected technology.
Note on entry: Profiles are codestream limitations.
3.54 quantization: Method of reducing the precision of the individual coefficients to reduce the number of bits used
to represent them.
Note on entry: Quantization can be achieved by an explicit operation with a given quantization value (scalar quantization) or by
dropping (truncating) coding passes from the codestream.
3.55 reconstructed image: Image that is the output of a decoder.
3.56 reference grid: Regular rectangular array of points used to define other rectangular arrays of data.
Note on entry: The reference grid is used to determine the number of samples in tile-components for example.
3.57 region of interest (ROI): Collection of coefficients that are considered of particular relevance by some user-
defined measure.
3.58 reversible: Transformation, progression, system, or other process that does not suffer systemic or quantization
error and therefore allows for lossless signal recovery.
3.59 reversible filter: Particular filter pair used in the wavelet transformation which allows lossless compression.
3.60 sample: One element in the two-dimensional array that comprises a component.
3.61 selective arithmetic coding bypass: Coding style where some of the code-block passes are not coded by the
arithmetic coder, where the bits to be coded are instead appended directly to the bitstream without coding.
3.62 shift: Multiplication or division of a number by powers of two, where ivision of an integer via shift implies
truncation toward minus infinity of the non-integer portion.
3.63 sign bit: Bit that indicates whether a number is positive (value 0) or negative (value 1).
3.64 sign-magnitude notation: Binary representation of an integer where the distance from the origin is expressed
with a positive number and the direction from the origin (positive or negative) is expressed with a separate single sign
bit.
3.65 source image: Image used as input to an encoder.
3.66 sub-band: Group of transform coefficients resulting from the same sequence of low-pass and high-pass filtering
operations, both vertically and horizontally.
3.67 testing: Process of evaluating compliance.
3.68 tile: Rectangular array of points on the reference grid, registered with an offset from the reference grid origin
and defined by a width and height.
3.69 tile-component: All the samples of a given component in a tile.
3.70 tile-part: Portion of the codestream with compressed image data for some, or all, of a tile, including one or
more packets that make up the coded tile.
3.71 tile-part header Group of markers and marker segments at the beginning of each tile-part in the codestream
that describe the tile-part coding parameters.
3.72 transformation: Mathematical mapping from one signal space to another.
3.73 transform coefficient: Value that is the result of a transformation.
4 Abbreviations and symbols
4.1 Abbreviations
For the purposes of this Recommendation | International Standard, the abbreviations given in Rec. ITU-T T.800 | ISO/IEC
15444-1 and the following apply.
ATS Abstract Test Suite
BSET subset of the ETS consisting of HTJ2K test codestreams that differ only by B value
MAGB
ETS Executable Test Suite
HT High Throughput
4 Rec. ITU-T T.803 (V3) (02/2024)
© ISO/IEC 2024 – All rights reserved

HTJ2K High Throughput JPEG 2000
ICC International Colour Consortium
ICS Implementation Compliance Statement
ICT Irreversible Component Transform
IDWT Inverse Discrete Wavelet Transformation
IEC International Electrotechnical Commission
ISO International Organization for Standardization
ITU International Telecommunication Union
ITU-T International Telecommunication Union – Telecommunication Standardization Sector
IUT Implementation Under Test
J2K JPEG 2000
JPEG Joint Photographic Experts Group
MAGB Magnitude Bound
MSE Mean Squared Error
RCT Reversible Component Transform
ROI Region Of Interest
sRGB standard Red–Green–Blue
TCS Test Codestream
4.2 Symbols
For the purposes of this Recommendation | International Standard, the following symbols apply.
0x---- Denotes a hexadecimal number
B Bit-depth precision for reversible 5-3
B Magnitude bound parameter for an HTJ2K codestream
MAGB
C Component guaranteed to be decoded
CAP Capabilities
COC Coding style Component
COD Coding style Default
COM Comment
CPF Corresponding Profile
CRG Component Registration
EPH End of Packet Header
EOC End of Codestream
H image Height guarantee
L Layer guarantee
L code data buffering guarantee
body
M decoded bit-plane guarantee
M Magnitude bound decoding guarantee
MAGB
N code-block parsing guarantee
cb
N component parsing guarantee
comp
P irreversible 9-7 Precision guarantee
PLM Packet Length, Main header marker
PLT Packet Length, Tile-part header marker
____________________
As defined in Rec. ITU-T T.800 | ISO/IEC 15444-1.
Rec. ITU-T T.803 (V3) (02/2024) 5
© ISO/IEC 2024 – All rights reserved

POC Progression Order Change marker
PPM Packed Packet headers, Main header marker
PPT Packed Packet headers, Tile-part header marker
PRF Profile marker
QCC Quantization Component marker
QCD Quantization Default marker
RGN Region of interest marker
SIZ image and tile Size marker
SOC Start Of Codestream marker
SOD Start Of Data marker
SOP Start Of Packet marker
SOT Start Of Tile-part marker
T Transform level guarantee
L
TLM Tile-part Lengths marker
W image Width guarantee
5 Conventions
The compliance files including test codestreams, JP2 files, JPH files, reference decoded images, and descriptive files are
supplied in the form of a compressed file. File locations given in this Recommendation | International Standard are
expressed relative to the top level of the directory tree. A Unix style file structure and delimiters are assumed.
This Recommendation | International Standard contains instructions for the use of these files. No support can be provided
by ISO | ITU-T beyond that offered in this Recommendation | International Standard.
6 General description
Perhaps the most distinctive feature of JPEG 2000 is its emphasis on and support for scalability. An existing codestream
may be accessed at a reduced resolution, at a reduced quality (higher compression), at a reduced number of components,
and even over a reduced spatial region. Moreover, this Recommendation | International Standard supports a rich family
of information progression sequences whereby the information may be reordered without introducing additional
distortion. This enables a single compressed codestream to serve the needs of a diverse range of applications.
This Recommendation | International Standard also covers compliance for implementations of Rec. ITU-T T.814 |
ISO/IEC 15444-15. To avoid confusion, the terms JPEG 2000 (J2K) and high throughput JPEG 2000 (HTJ2K) are used
in this Recommendation | International Standard, where necessary, to differentiate between JPEG 2000 codestreams that
conform to Rec. ITU-T T.800 | ISO/IEC 15444-1 and those that conform to Rec. ITU-T T.814 | ISO/IEC 15444-15,
respectively. J2K codestreams can be reversibly transcoded to HTJ2K and vice-versa, without any loss in information.
This property allows compliance for HTJ2K and J2K implementations to be treated in a very similar manner. In fact, all
of the HTJ2K test codestreams and JPH files provided in the electronic attachment have been obtained by reversibly
transcoding corresponding J2K test codestreams and JP2 files available at the same location. The decoded output from an
HTJ2K decoder is expected to conform to the same guidelines as the decoded output from a J2K decoder, processing the
corresponding J2K codestream or JP2 file.
From the perspective of compliance, the main distinction between HTJ2K and J2K is that an HTJ2K codestream does not
generally possess the same quality scalability attributes as the corresponding J2K codestream. An HTJ2K decoder cannot
choose to stop the decoding of a code-block bit-stream at an arbitrary bit-plane, providing a fine grain trade-off between
implementation complexity and reconstructed image quality. Considering this dif
...