DCA Metadata#

DCA metadata lives in the zarr.json of the multiscales image group (i.e. the same level as ome.multiscales), under the dca key, enabling varying channel composition at arbitrary levels of the OME-Zarr hierarchy. In an OME-Zarr HCS layout this is the field-of-view level (e.g. plate.ome.zarr/A/3/0/zarr.json).

The dca object MUST contain:

  • version — a string specifying the version of this specification (currently "0.2")

  • url — a URL pointing to the specification in the GitHub repository

  • channels — an array of channel metadata objects (see Channel Metadata Specification)

  • normalization_statistics — per-channel normalization statistics keyed by channel index (see Normalization Statistics Specification)

{
  "ome": {
    "multiscales": [ "..." ]
  },
  "dca": {
    "version": "...",
    "url": "...",
    "channels": [ "..." ],
    "normalization_statistics": { "..." }
  }
}

See the JSON Schema for the authoritative definition.

Experimental metadata (acquisition, study/sample, perturbation) is not stored in this dca block — it is agent-curated into a sibling Parquet (see Experimental Metadata Specification).