ISO/IEC 18181-2:2024 情報技術 — JPEG XL 画像符号化システム — Part 2:ファイル形式 | ページ 2

Foreword

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This document was prepared by 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 18181-2:2021), which has been technically revised.

The main changes are as follows:

• Cross-references to ISO/IEC 18181-1 are updated to match its second edition;
• The JPEG bitstream reconstruction procedure was moved to Annex A and revised to improve clarity;
• Annex B was added, specifying the image/jxl media type registration.

A list of all parts in the ISO/IEC 18181 series can be found on the ISO and IEC websites.

1 Scope

This document specifies the transport and container formats for JPEG XL codestreams as specified in ISO/IEC 18181-1. This document specifies how to add metadata and extensions to JPEG XL codestreams. A file as described by this document is called a JPEG XL file.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

Bibliography