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


    • 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.


    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
    • Text line
    • Text zone
    • Word
    • Paragraph
    • Illustration
    • Decoration
    • Chart
    • Table
    • Signature

    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
    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
    Element Types management in the web interface

    API Endpoints🔗

    Types are listed when retrieving a project from the API: