Zoom: Ctrl+scroll
Next annotated object in image: Tab
Next image: F
Previous image: D
Undo: Ctrl+z
Hide box: H
Set box to Occluded: Q
(use when box is covered by another tool or if tool is offscreen)
Copy: Ctrl+C
Paste: Ctrl+V
Delete (for mac): Fn+Delete
Hide all boxes on frame: T + H