JSON-HD (High Definition Metadata)

JSON-HD is a hybrid metadata container format: a human-readable JSON manifest plus efficient payload storage (binary and/or files), designed for interoperability, integrity, and partial access.

Think: “JSON for meaning + structured payloads for scale.”

What you get

• A canonical manifest.json you can parse instantly (discovery + indexing).
• Payloads stored efficiently (ZIP profile today, HDF5 profile next).
• Strong linking from manifest → payloads (URIs, byte ranges, dataset paths).
• Built-in integrity hooks (hashes, sizes, validation rules).
• Extensible by design (namespaced extensions, forward-compatible parsing).

Status

• Core Spec: v0.1 (draft)
• ZIP Profile: v0.1 (draft, reference samples included)
• HDF5 Profile: planned (RFC in progress)

Quick start (ZIP profile)

A .jsonhd file is a ZIP container with:

• /manifest.json (required)
• /payload/** (payload files)
• optional /schemas/**, /signatures/**, /provenance/**

Minimal example

See: samples/zip-minimal/

Repo map

• SPEC.md — Core spec (normative language: MUST/SHOULD/MAY)
• profiles/ — Packaging profiles (ZIP, HDF5, etc.)
• schemas/ — JSON Schemas for manifest validation
• samples/ — Test vectors (canonical examples)
• tools/ — Reference tooling (CLI validators/builders)

Contributing

See CONTRIBUTING.md. We use lightweight RFCs in rfcs/.

License

Apache-2.0 (see LICENSE).