Annotate — Keyboard Reference

:::tip TL;DR

• All annotation is keyboard-first: one hand on keyboard, one on pointing device
• Tool keys are single-key with no modifiers: P (point), B (box), T (temporal event)
• Number keys 1–6 quick-set the type of the selected event
• ? toggles the in-app shortcut cheat sheet :::

The Annotate tool is built for speed. Learning the shortcuts below is the single highest-leverage action for annotation throughput. (Authoritative source: the keydown handler in src/App.tsx and src/components/ShortcutModal.tsx.)

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Global Controls

Key	Action
Space	Play / Pause
J	Reverse playback (press again while reversing to ramp 2× → 4×)
K	Pause
L	Forward playback (press again while forwarding to ramp 2× → 4×)
←	Frame step backward
→	Frame step forward
Shift + ←	Jump 10 frames backward
Shift + →	Jump 10 frames forward
Cmd/Ctrl + Z	Undo
Cmd/Ctrl + Shift + Z	Redo
Cmd/Ctrl + O	Load project
Cmd/Ctrl + S	Save project
Cmd/Ctrl + E	Export dataset
?	Toggle the shortcut cheat sheet
Esc	Close the shortcut modal, else deselect + return to the select tool

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Tool Selection

Single-key with no modifiers. Pressing a tool key activates it; Esc returns to the select tool.

Key	Tool	Behavior
P	Point	Click to place a point annotation (x, y, time)
B	Box	Click-drag to draw a bounding box (x1, y1, x2, y2, time)
T	Temporal Event	If an event is currently open, T closes it; otherwise it activates the event tool
Esc	Select / deselect	Returns to the select tool and clears the current selection

There is no skeleton/pose (S) or polygon/mask (G) tool. The Tool type is select | point | box | event.

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Event Type Quick-Set

With a temporal event selected, press a number key to set its type (only types allowed by the current context apply):

Key	Event type
1	serve
2	shot
3	bounce
4	point_end
5	net_hit
6	out

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Annotation Editing

Action	Shortcut
Move annotation	Click + Drag
Delete selected	Delete / Backspace

All edits are non-destructive — undo/redo history (Cmd/Ctrl+Z / Shift+Z) and a dirty-state indicator track every change.

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Context Selection

Context is set via the in-app Context modal (UI), not a keyboard shortcut. It controls which event types are valid.

Context	Label
match	Competitive point-based play
practice	Practice rally or solo on-court practice
training_off_court	Wall drills, ball machine, gym
highlight_clip	Edited broadcast or short clip
unknown	Tennis-like but ambiguous

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Context → Allowed Events

The UI automatically enables and disables tools based on selected context. Attempting to annotate a disallowed event type is blocked.

Context	Allowed events	Disallowed events
match	serve, shot, bounce, net_hit, out, point_end	—
practice	shot, bounce	serve, point_end
training_off_court	shot	bounce, serve, point_end
highlight_clip	shot, point_end	bounce, serve, net_hit, out

:::warning Why this matters Annotating a serve in a practice context would produce invalid training data. The UI enforces these rules — tool keys for disallowed events produce no action. :::

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Annotation Workflow (Speed Run)

Typical flow for annotating one rally:

1. Space — play video
2. K or Space — pause on event frame
3. ← / → — fine-tune to the exact frame
4. Press a tool key (P, B, or T) — activate the tool
5. Click / drag to place the annotation
6. With an event selected, press 1–6 to set its type
7. Cmd/Ctrl+S to save; repeat from step 1

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Next Steps

• Annotate Overview — architecture and data model
• Pipeline Stages — how the GPU backend produces events the annotate tool validates
• Output Schema — events_timeline.json format used for comparison