Type

Using appropriate types is crucial for a project, as it will ensure a clear structure between elements.

Rules

  • Arkindex do not assume any structure for a Project types, the Project administrator is free to create as many types as needed.

  • Type has a unique (per project) identifying slug, which is used by API endpoints to simplify its usage (instead of using its ID)

  • It also has a display name, which is only used for display purposes and has no restrictions

  • A Type has a boolean folder attribute: when set to True, the web interface will always display the associated elements as a folder containing other elements, instead of displaying its details.

Folders

Element types can also specify whether their elements are folders, which is nothing more than a display option; the frontend will display folders as a list of their child elements, whereas regular elements are expected to be on an image.

Default types

When creating a new project on Arkindex, you will get a pre-defined set of types:

  • a folder named Folder

  • Page

  • Paragraph

  • Text line

  • Text zone

  • Word

Feel free to change them as desired before importing your content.

Historical books example

A project with historical books could have the following simple structure:

Example of Element structure for an historical project
Figure 1. Example of Element structure for an historical project

In this example, we have 4 different Element types:

  • Volume is a folder, that will be used to group several elements of type Page

  • Page represent a single page of a Volume. These elements will be directly linked to an image provided by the client.

  • Paragraph will be created either by a human annotator, or by a Machine Learning tool. A Paragraph may span over several sections of Page.

  • Line will generally be generated by a Machine Learning tool. In this case it could either be directly linked to a Page and/or a Paragraph.

Web interface

As a project administrator, you can edit its types from the project edition page.

You’ll then get access to a table listing all the available types, and the different possible actions:

  • Adding a new type (last line)

  • Edit the display name, identifying slug, and folder type.

Element Types management in the web interface
Figure 2. Element Types management in the web interface

API Endpoints

Types are listed when retrieving a project from the API: