Summary

Rec. ITU-T T.800 | ISO/IEC 15444-1 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.

This Recommendation | International Standard provides the framework, concepts, and methodology for testing and the 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. The objective of standardization in this field is to promote interoperability between JPEG 2000 encoders and decoders and to test these systems for compliance to this Recommendation | International Standard. Compliance testing is the testing of a candidate product for the existence of specific characteristics required by a standard. It involves testing the capabilities of an implementation against both the compliance requirements in the relevant standard and the statement of the implementation's capability.

The purpose of this Recommendation | International Standard is to define a common test methodology, to provide a framework for specifying abstract test suites (ATSs), and to define the procedures to be followed during compliance testing.

Any organization contemplating the use of test methods defined in this Recommendation | International Standard should carefully consider the constraints on their applicability. Compliance testing does not include robustness testing, acceptance testing, and performance testing.

NOTE – This Recommendation | International Standard is in its third edition from the International Telecommunication Union (ITU) and in its fourth edition from the International Organization for Standardization /International Electrotechnical Commission (ISO/IEC).

This edition cancels and replaces the previous edition which has been technically revised.

The main changes compared to the previous edition 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.

This Recommendation | International Standard contains a normative electronic attachment with the codestreams used in the application of the procedures described herein that is available from ITU at https://www.itu.int/net/itu-t/sigdb/speimage/ImageForm-s.aspx?val=10100803 or from ISO at https://standards.iso.org/iso-iec/15444/-4/ed-4/en.

Source

This document was prepared by Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information, in collaboration with ITU-T Study Group 16. An identical text is published as ISO/IEC 15444-4:2021.