Version History#

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog.

0.6rc0 - 2026-07-01#

Added#

  • RFC5 adopted: Transformations, coordinate systems and scene metadata.

  • Added projectAxis transform to add or drop dimensions at specified indices of the coordinate vector.

  • Added suggestion on which coordinate system to use for display in the spec document.

  • New projectAxis transformation to add or drop dimensions explicitly.

Changed#

  • BREAKING CHANGE: Unified input and output fields in all transformation metadata to be an object of {"name": string, "path": string} instead of allowing both string and object forms. This change was made to ensure consistency across all transformations and to simplify the specification.

  • BREAKING CHANGE: Replaced arrayCoordinateSystems with explanation of how to properly express dimensionless transforms.

  • BREAKING CHANGE: input_axes and output_axes in byDimension transformations are now written in camelCase (inputAxes and outputAxes) to be consistent with other transformations.

  • Displacements and coordinate transformations are now required to store the vector field as a normal multiscale group with the same metadata as other multiscales. Decided at EMBL Hackathon 06/2026 by RFC5 developers.

  • Additional requirements for displacement or coordinate axis "type" and discrete fields (now required).

  • General wording improvements in the spec document for clarity and consistency.

Removed#

  • Removed version field from multiscales metadata in the image schema (schemas/image.schema) since it is already required at ome > version

  • Removed version field from plate, well and labels metadata in the spec document since it is already required at ome > version.

[0.6.dev4] - 2026-04-22#

Changed#

  • BREAKING CHANGE: Unified input and output fields in all transformation metadata to be an object of {"name": string, "path": string} instead of allowing both string and object forms. This change was made to ensure consistency across all transformations and to simplify the specification.

  • BREAKING CHANGE: Replaced arrayCoordinateSystems with explanation of how to properly express dimensionless transforms.

  • style: Improved readability of multiscales section and coordinates/displacements transformations.

[0.6.dev3] - 2026-03-13#

Changed#

  • Implemented feedback from Hackathon:

    • BREAKING CHANGE: Renamed top-level group for transformations to “Scene”

    • BREAKING CHANGE: Transformations in scene metadata must be object with fields “name” and “path”

    • BREAKING CHANGE: Made syntax of mapAxis and byDimension transforms consistent with other transforms

    • BREAKING CHANGE: Zarr parameter storage no longer allowed for scale/translation

    • For detailed set of changes see complete overview

  • Updated version keys from 0.6.dev2 to 0.6.dev3 everywhere

  • style: Homogeneous use of backticks in spec document

  • specification: Changed the constraints for valid path values in wells for HCS plates to allow some non-alphanumeric characters.

  • specification: Corrected that version field is not required under plate/well/labels metadata.

  • specification: Constrained datatype of multiscales datasets to be the same across all resolutions

  • specification: Clarified that name field in axes metadata is required to be a non-empty string.

  • style: Adopted JSON terminology for “object” and “array” in the spec document.

Removed#

  • BREAKING CHANGE: Removed inverseOf transformation

  • Removed version field from multiscales metadata in the image schema (schemas/image.schema) since it is already required at ome > version

  • Removed version field from plate, well and labels metadata in the spec document since it is already required at ome > version.

[0.6.dev2] - 2025-12-02#

Changed#

Implemented feedback from RFC-5 review 1 and 2

[0.6dev1] - 2025-11-18#

Added#

Initial proposal for RFC-5: Transforms. See proposal text.

[0.5.2] - 2025-01-10#

Changed#

  • Clarify that the dimension_names field in axes MUST be included.

[0.5.1] - 2025-01-10#

Added#

  • Re-add the improved omero description in PR-191.

[0.5.0] - 2024-11-21#

Changed#

  • Use Zarr v3 in OME-Zarr, see RFC-2.

  • Expand on “labels” description and clarify only integer data types are supported

[0.4.1] - 2022-09-26#

Added#

  • transitional metadata for image collections (“bioformats2raw.layout”)

[0.4.0] - 2022-02-08#

Added#

  • multiscales: add axes type, units and coordinateTransformations

  • plate: add rowIndex/columnIndex

[0.3.0] - 2021-08-24#

Added#

  • Add axes field to multiscale metadata

[0.2.0] - 2021-03-29#

Changed#

  • Change chunk dimension separator to “/”

[0.1.4] - 2020-11-26#

Added#

  • Add HCS specification

[0.1.3] - 2020-09-14#

Added#

  • Add labels specification

[0.1.2] - 2020-05-07#

Added#

  • Add description of “omero” metadata

[0.1.1] - 2020-05-06#

Added#

  • Add info on the ordering of resolutions

[0.1.0] - 2020-04-20#

First version for internal demo