Overview
ISO/IEC 15444-16:2025 specifies the encapsulation of JPEG 2000 codestreams into ISO Base Media File Format (ISOBMFF) derivatives based on ISO/IEC 14496-12, including the image file format defined in ISO/IEC 23008-12. The third edition updates encapsulation rules to allow more flexible colour signalling, explicitly standardizes JPEG 2000 in ISOBMFF, and defines structures for JPEG 2000 video tracks. This standard is essential for reliably packaging JPEG 2000 images, image sequences and video tracks for file interchange, storage and streaming.
Key Topics
- Scope: Encapsulation of JPEG 2000 codestreams as individual images, image collections, image sequences, and video tracks in ISOBMFF-based file formats.
- Coded image item: Use of item type 'j2k1' for JPEG 2000 coded image items; body must be exactly one Contiguous Codestream box (per ITU‑T T.800 / ISO/IEC 15444-1).
- Header item property: Mandatory association with a 'j2kH' (JPEG 2000 header) item property whose essential field equals 1; the j2kH mirrors JP2 Header Box contents with controlled exceptions:
- Colour Specification box can be omitted because colour may be signalled at the ISOBMFF layer.
- Channel Definition box is required.
- Image Header box is optional (information can be inferred from ISOBMFF or the codestream).
- Defined fields within j2kH: channels, components, palette, resolution, bits-per-component (bpcc), pixel format and layers (layers box is specified in clause 6.4).
- Conformance rules: File and reader conformance clauses, media type registration and consistency constraints (e.g., ispe, pixi, pasp vs SIZ marker fields).
- Compatibility: Guidance for backward compatibility (e.g., optional association with 'colr' item property for older implementations).
Applications
- Packaging JPEG 2000 images for digital media distribution, streaming and adaptive delivery using ISOBMFF containers.
- Enabling image sequences and video tracks with JPEG 2000 compression for broadcast, cinema, archival and professional imaging workflows.
- Implementers of media players, encoder/decoder libraries, file format tools and DAM (digital asset management) systems that need standardized interchange of JPEG 2000 content.
- Preservation and archival systems that require precise metadata mapping between JPEG 2000 codestreams and ISOBMFF item properties.
Related Standards
Keywords: ISO/IEC 15444-16:2025, JPEG 2000, encapsulation, ISOBMFF, ISO/IEC 14496-12, Contiguous Codestream, j2k1, j2kH, image file format.