Overview
ISO/IEC 19566-7:2022 - JPEG linked media format (JLINK) specifies an image file container and metadata model for linking multiple media elements (for example, images and text) inside any box‑based JPEG file format. JLINK defines the concepts of a scene (2D image plus text, viewports, title/note) and a link (linkage region, sprite and visual effect) to build interactive, navigable image experiences in a single file. Metadata for JLINK is structured using the JPEG Universal Metadata Box Format (JUMBF).
Keywords: ISO/IEC 19566-7:2022, JLINK, JPEG linked media format, JUMBF, linked media, scene, link, viewport, sprite, linkage region.
Key topics and technical requirements
- Scene and Link model: A scene contains a 2D image, optional viewports (center X/Y and field‑of‑view spans given as percent ratios), title and note. A link binds a source scene to a destination scene.
- Linkage regions: Active regions on a source image defined as a point, rectangle or ellipse. Positions and sizes are expressed as percent ratios relative to the scene image.
- Sprites and UI events: Overlaid visual elements (sprites) mark linkage regions and receive user interactions that trigger scene changes.
- Scene transitions: JLINK specifies visual effects for scene change (jump‑in / jump‑out) and how viewers should prepare and present the destination scene.
- Metadata structure: JLINK metadata is carried in JUMBF boxes (ISO/IEC 19566‑5 is the normative reference). Destination scenes and image codestreams are referenced via JUMBF URIs.
- Identifiers and conventions: Viewports have integer IDs (1…n; 0 reserved to indicate the whole image). The standard uses percent-based coordinates to ensure resolution‑independent presentation.
- Compatibility: JLINK supports integration with legacy image coding and metadata technologies by embedding references and standardized metadata boxes.
Applications
- Interactive image tours and annotated photography (museums, cultural heritage)
- Digital publishing and editorial illustrations with embedded annotations and navigation
- E‑commerce: product images with clickable regions leading to detail views or descriptions
- Educational materials and technical diagrams with linked explanatory text
- Multimedia archiving and packaging: bundling images, captions and navigation inside a single JPEG‑box file
Who should use this standard
- Software developers building image viewers, galleries or multimedia players
- Digital asset managers and content creators packaging interactive images
- Archivists and publishers wanting portable, metadata‑rich image packages
- Vendors and implementers of JPEG box‑based formats looking for standardized linking and navigation
Related standards
- ISO/IEC 19566‑5 - JPEG universal metadata box format (JUMBF) - normative reference
- Other parts of the ISO/IEC 19566 JPEG systems series (JPEG systems metadata and container standards)
For implementers, ISO/IEC 19566‑7:2022 provides a clear model for embedding interactive, linked media inside JPEG box containers while maintaining resolution independence and metadata interoperability.