Overview

ISO/IEC 18477-4:2017 - part of the JPEG XT family - defines the framework and procedures for conformance testing of scalable compression and coding of continuous‑tone still images. It provides the methodology, test concepts and criteria that implementations must meet to claim conformance to one or more parts of the ISO/IEC 18477 series (commonly referred to as JPEG XT). The standard focuses on decoder and codestream conformance rather than performance, robustness or acceptance testing.

Key topics and technical requirements

Scope of conformance testing: Procedures for decoder conformance to ISO/IEC 18477-1, -2, -6, -7, -8 and -9, and for codestream conformance to those parts.
Abstract Test Suites (ATS): A framework for specifying generic test cases that cover required functionality for each part and profile.
Implementation Conformance Statement (ICS): Guidance for declaring which parts/profiles an implementation claims to support.
Test artifacts and metrics: Specification of codestreams, decoded images and error metrics used within decoder testing procedures.
Normative annexes: Includes decoder conformance testing procedures (Annex A), decoder conformance tests (Annex B) and codestream conformance (Annex C).
Conventions and definitions: Common terminology, operators and test language for consistent conformance interpretation.
Out of scope: Robustness testing, acceptance testing and performance testing are explicitly excluded.

Practical applications and target users

Who uses this standard:

Codec and imaging software developers implementing JPEG XT features (HDR, lossless/near‑lossless, alpha channel, integer coding).
Test laboratories and certification bodies performing interoperability and conformance assessments.
Hardware vendors and system integrators validating decoders and codestream producers for compliance.
Product QA teams ensuring implementations meet formal conformance claims in their Implementation Conformance Statements.

Why it matters:

Enables consistent, repeatable conformance testing to promote interoperability of JPEG XT decoders and codestream producers.
Provides a shared test methodology and specimens (codestreams and decoded references) that reduce ambiguity in compliance claims.
Supports adoption of scalable compression for high-dynamic-range (HDR) and other extended imaging workflows while preserving compatibility with legacy JPEG decoders.

Related standards

ISO/IEC 18477 series (JPEG XT): Parts 1, 2, 3, 6, 7, 8, 9
ISO/IEC 10918-1 (ITU-T T.81) - baseline JPEG compatibility

Keywords: ISO/IEC 18477-4:2017, JPEG XT, conformance testing, abstract test suite, codestream conformance, decoder testing, scalable compression, HDR imaging, Implementation Conformance Statement.

Overview

Key topics and technical requirements

Scope of conformance testing: Procedures for decoder conformance to ISO/IEC 18477-1, -2, -6, -7, -8 and -9, and for codestream conformance to those parts.
Abstract Test Suites (ATS): A framework for specifying generic test cases that cover required functionality for each part and profile.
Implementation Conformance Statement (ICS): Guidance for declaring which parts/profiles an implementation claims to support.
Test artifacts and metrics: Specification of codestreams, decoded images and error metrics used within decoder testing procedures.
Normative annexes: Includes decoder conformance testing procedures (Annex A), decoder conformance tests (Annex B) and codestream conformance (Annex C).
Conventions and definitions: Common terminology, operators and test language for consistent conformance interpretation.
Out of scope: Robustness testing, acceptance testing and performance testing are explicitly excluded.

Practical applications and target users

Who uses this standard:

Codec and imaging software developers implementing JPEG XT features (HDR, lossless/near‑lossless, alpha channel, integer coding).
Test laboratories and certification bodies performing interoperability and conformance assessments.
Hardware vendors and system integrators validating decoders and codestream producers for compliance.
Product QA teams ensuring implementations meet formal conformance claims in their Implementation Conformance Statements.

Why it matters:

Enables consistent, repeatable conformance testing to promote interoperability of JPEG XT decoders and codestream producers.
Provides a shared test methodology and specimens (codestreams and decoded references) that reduce ambiguity in compliance claims.
Supports adoption of scalable compression for high-dynamic-range (HDR) and other extended imaging workflows while preserving compatibility with legacy JPEG decoders.

Related standards

ISO/IEC 18477 series (JPEG XT): Parts 1, 2, 3, 6, 7, 8, 9
ISO/IEC 10918-1 (ITU-T T.81) - baseline JPEG compatibility

Keywords: ISO/IEC 18477-4:2017, JPEG XT, conformance testing, abstract test suite, codestream conformance, decoder testing, scalable compression, HDR imaging, Implementation Conformance Statement.

ISO/IEC 18477-4:2017 PDF

Technical details

Abstract

Overview

Key topics and technical requirements

Practical applications and target users

Related standards

Related standards

Abstract

Overview

Key topics and technical requirements

Practical applications and target users

Related standards

Related standards

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