Type example — an Image type

Image (image.py) is the smallest useful custom type: a 2-D micrograph built on the core Array. Copy the folder's file into your project's types/ — the registry picks it up on reload, and the project has a type called Image.

What a subclass adds (and what it inherits)

The core types are the ones SciStudio knows how to store and reload — Array keeps its data in a chunked Zarr store. A subclass inherits all of that and adds only meaning:

• A name. The class name is the registered type name; it appears in the Data types tab, in port type lists, and in the Load block's core_type choices.
• Rules. required_axes = frozenset({"y", "x"}) means an Image constructed without both spatial axes raises — a block that declares Image on a port can rely on y and x being present. (allowed_axes and canonical_order are the other two knobs; see the Array page in the API reference.)
• Appearance (optional). This example declares no colors: a subclass that says nothing inherits its parent's fill and gets an outline of its own, so an Image reads as "an Array, but a particular one" on every port. A type that wants its own declares ui_color / ui_ring_color as CSS hex strings.

Subtype flows with it: because an Image is an Array, every port, panel, and plot that accepts Array accepts an Image.

The type is half the story

A type nobody can load is unusable, so a real project pairs it with a loader: the IO block example teaches the Load block to read .tif files into this Image, and the process example consumes it. For typed metadata (a frozen Pydantic model on Meta), see the custom-types.md page of this guide.