Overview
ISO/IEC 23090-7:2022, part of the ISO/IEC 23090 series, defines immersive media metadata for coded representation of immersive videos (including 360° video) and images. The standard specifies common metadata structures, syntax and semantics used to describe reference coordinate systems, rotations, content coverage, viewpoints, projection formats and region-wise packing. Its goal is to provide reusable metadata building blocks that other standards and implementations can reference when encoding, packaging or rendering immersive media.
Key technical topics and requirements
- Common metadata and coordinate systems
- Definitions for a common reference coordinate system, local/global coordinate axes, azimuth/elevation (sphere coordinates) and rotation structures.
- Data structures describing content coverage (sphere regions) and viewpoint information.
- Metadata syntax and semantics
- Detailed syntax structures and semantic rules for interpreting metadata elements such as rotation, sphere regions, and quality ranking for regions.
- Video & image metadata
- Specification of projection formats (e.g., equirectangular, cubemap) and their metadata descriptions.
- Region-wise packing formats and mapping between packed pictures and projected regions.
- Sample location mapping: mapping decoded picture sample locations to sphere coordinates and relating decoded content to global axes.
- Support for fisheye omnidirectional video metadata and associated structures.
- Data models
- Concrete metadata structures for projection formats, region-wise packing, fisheye video, and semantics for how to use them in file formats and containers.
- Reusability
- Metadata designed to be referenced by other standards and media formats; normative references include ISO/IEC 14496-12 (ISO base media file format) and ISO/IEC 23008-12 (image file format).
Practical applications
- Ensures consistent interpretation of orientation, viewport and region quality across the immersive media pipeline:
- Content creators and capture-device manufacturers (360/VR cameras, fisheye lenses) for accurate metadata embedding.
- Codec and file-format implementers for packaging immersive video in MP4/HEIF-based containers.
- Playback and rendering engines, VR/AR platforms and media players to correctly map pixels to sphere coordinates and apply viewport-based streaming.
- Streaming services and CDN workflows that use region-wise quality ranking and packing for bandwidth-efficient delivery.
Who should use this standard
- Multimedia software engineers, encoder/decoder developers, immersive media researchers, camera and headset manufacturers, and standards authors who need interoperable metadata definitions for immersive and omnidirectional content.
Related standards
Keywords: ISO/IEC 23090-7, immersive media metadata, 360 video, omnidirectional video, projection formats, region-wise packing, coordinate system, fisheye video, metadata structures, sphere coordinates.