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Common Canvas Tools

Annotation Tools

Selector Selector Icon

This tool allows users to click and drag annotations, or adjust existing bounding boxes. To select more than one annotation at a time, click and drag a box around them, or hold down the Shift button as you select each one. Use Tab as a hotkey to move from one annotation to the next.

Selector Tool

Zoom Zoom Icon

Annotators can zoom in several ways:

  • using the zoom dropdown or ‘fill space’ button (Fill Space Icon) in the top right corner
  • using the zoom tool to click or Shift + click to zoom in or out, or to click and drag to view a region of the image
  • sliding the scale underneath the image navigator in the classes panel
  • scrolling the mouse wheel

Zoom Tool

Context Menu

Annotators can access the context menu by right clicking an image, annotation, or multiple annotations. Depending on the selection, the context menu allows annotators to:

  • delete the selected annotation(s)
  • change the class of the selected annotation(s)
  • fill holes in a segmentation mask
  • 'ungroup' a multi-polygon instance into multiple instances
  • 'group' multiple instances into one
  • copy and paste a bounding box annotation - including its metadata - directly in the canvas
  • view an annotation's metadata
  • hide the selected annotation
  • hide all annotations except the selected annotation

Context Menu

Workflow Tools

Workflow Options Reset Video Icon Back Icon Forward Icon

Annotators can go back, forward, and reset the annotation canvas entirely using these buttons. Undo and redo can also be accessed by Ctrl + z and Ctrl + y.

Work Options

Save Reset Video Icon

To periodically save work, annotators can hit the save button next to the workflow options. Annotators will always be prompted to save their work before leaving the canvas if any unsaved work exists. If work is saved but not submitting, any pending annotation locks will be shown by clicking on the task's progress bar, as described here.

Submit Submit Icon

The submit button allows the annotator to submit their annotations and move on to the next piece of data to annotate. Once annotations are submitted, only project members with supervisor access can view and edit those annotations. Annotators can also submit work using the hotkey combination Shift + Enter.


Flag Flag Icon

This button allows annotators to flag work and move to the next item to annotate. Flagging work will submit a piece of work and generate a message to the task creator that allows them to view that specific image and annotation set in the canvas to address the concern.

Work History

Use the work history panel while annotating to navigate back to recent submissions and edit when necessary. As you annotate, your last ten annotations will be displayed in the history panel, with the most recent submission at the top.

Image History