ISO/IEC 21122-4:2022

Information technology — JPEG XS low-latency lightweight image coding system — Part 4: Conformance testing

This document specifies the framework, concepts, methodology for testing, and criteria to be achieved to claim conformance to multiple parts of the ISO/IEC 21122 series. It lists the conformance testing procedures. This document specifies: — Conformance testing procedures for decoders implementing ISO/IEC 21122-1. — Tests to check which conformance point an ISO/IEC 21122-1 decoder conforms to, that is, whether a decoder satisfies the error bounds required for strict or relaxed conformance. — Conformance testing procedures for decoders implementing ISO/IEC 21122-3. — Tests to check codestreams for conformance to ISO/IEC 21122-1. As such, it provides means to test whether encoder implementations generate syntactically correct codestreams, and whether codestreams generated by such implementations follow the requirements of a particular profile, level and sublevel, and the buffer model implied by them. — Tests to check files for conformance to ISO/IEC 21122-3. — Conformance testing procedures that allow testing whether codestreams conform to any of the profiles specified in ISO/IEC 21122-2. — Conformance testing procedures that allow testing whether codestreams conform to the buffer model specified in ISO/IEC 21122-2 as part of a profile, level and sublevel. — Codestreams, decoded images, and error metrics to be used within the decoder testing procedures. — A buffer model test. — Abstract test suites. NOTE: This document does not specify: — Testing the reconstruction of a full resolution image from a subsampled image format. In particular, upsampling from 4:2:2 or 4:2:0 to 4:4:4 sampling is a non-normative extension and as such its testing is beyond the scope of this document. — Testing the conversion of the sample values reconstructed by an ISO/IEC 21122-3 decoder to the target colour space by means of the colour specification box of ISO/IEC 21122-3. — Testing of the composition of background and foreground for images reconstructed from ISO/IEC 21122-3 files or codestreams that contain auxiliary channels carrying opacity information. — Testing of the interpolation of a colour filter array image to a full scale colour image; this process is not normatively defined and beyond the scope of this document. — 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, responsiveness, etc. under various conditions. — Robustness testing: the process of determining how well an implementation is able to conceal problems from attempting to reconstruct an image from an ill-formed codestream.

Technologies de l'information — Système de codage d'images léger à faible latence JPEG XS — Partie 4: Essais de conformité

General Information

• Status: Published
• Publication Date: 04-Oct-2022
• ICS: 35.040.30 - Coding of graphical and photographical information
• Technical Committee: ISO/IEC JTC 1/SC 29 - Coding of audio, picture, multimedia and hypermedia information
• Drafting Committee: ISO/IEC JTC 1/SC 29/WG 1 - JPEG Coding of digital representations of images
• Current Stage: 9092 - International Standard to be revised
• Completion Date: 19-Jan-2024

Relations

• Revises: ISO/IEC 21122-4:2020 - Information technology — JPEG XS low-latency lightweight image coding system — Part 4: Conformance testing
• Effective Date: 04-Dec-2021

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 21122-4
Second edition
2022-10
Information technology — JPEG XS
low-latency lightweight image coding
system —
Part 4:
Conformance testing
Technologies de l'information — Système de codage d'images léger à
faible latence JPEG XS —
Partie 4: Essais de conformité
Reference number
ISO/IEC 21122-4:2022(E)
© ISO/IEC 2022

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ISO/IEC 21122-4:2022(E)
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ii
  © ISO/IEC 2022 – All rights reserved

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ISO/IEC 21122-4:2022(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Abbreviated terms . 2
5 Overview . 3
6 General description . 3
6.1 Overview . 3
6.2 Codestream syntax testing. 3
6.3 Test procedures to test decoders for conformance to ISO/IEC 21122-1 . 3
6.4 Test procedures to test decoders for conformance to ISO/IEC 21122-3 . 3
6.5 File format syntax testing . 3
6.6 Profile, level and sublevel conformance testing . 4
6.7 Buffer model conformance testing . 4
6.8 Electronic attachments . 4
7 Conformance files availability and updates . 4
Annex A (normative) Codestream syntax testing procedures . 5
Annex B (normative) Decoder testing procedures . 6
Annex C (normative) Decoder conformance tests .10
Annex D (normative) File format syntax testing procedures .15
Annex E (normative) Buf
...