Group Manager

The group manager is one pane of the context sidebar.

Feature overview

DIVE supports complex group annotation.

• Groups can be interpreted as activity participation. For example, two Person type tracks participate in a Conversation activity.
• Groups can be used to represent most types of multi-annotation collections.
• Group membership for tracks can be explicitly constrained to sub-intervals within [track.begin, track.end]. A single track can belong to a group for multiple sub-ranges, typically interpreted as the tracked object leaving and re-joining a group.
• Tracks can belong to many different groups at once, and can have different participation interval(s) for each.

See the data format documentation for the complete capabilities of group annotations in the DIVE json schema.

Group List Controls

Group Type List

The group type summary list allows for enabling and disabling annotations based on their group and bulk-editing group type characteristics.

• Groups do not have separate "selected" and "editing" states, so selecting a group puts it into editing mode.
• Group type styles can be edited in the same fashion as track type styles in the left sidebar using (the edit pencil).

Group Instance List

Each group instance includes the following.

• A checkbox to enable and disable visibility
• The group id
• The group type
• A list of member track ids that are part of the group.

Group Editor

To enter group edit mode, click a group's ID number in the group list.

• Add new tracks to a group by first entering group edit mode, then selecting tracks to add (in the annotation window, the sidebar, or any UI where track selection can happen)
• (next to a track) will remove a track from a group.
• Use the frame range input boxes to adjust the start and end frame numbers that a track participates in a group.
• will set a frame input box to the current frame.
• will create a new sub-interval participation range for a track within a group.
• will remove a sub-interval participation range.
• Delete Group will delete a group without deleting its member tracks.

Some notes about group editing behavior.

• If you delete a track, and the track was the only track remaining in one or more groups, those groups will also be deleted.
• If you delete a group, its member tracks will not be deleted no matter how many members there are.
• The group's composite range (shown as disabled begin and end frames in the group editor) is the maximum overlapping range of all sub-intervals of all member tracks.

Example data

The group feature was initially developed for compatibility with the The Multiview Extended Video with Activities (MEVA) dataset. Find example data at mevadata.org.