Annotation Workbench
Understand the shared shell, item state, controls, and navigation.
Watch the multimodal Workbench in action
See how Unitlab brings modality-native editors into one operating model for ontology, item state, automation, review, and reproducible delivery.
Open the full-screen Unitlab AI explainer.
The Workbench is the shared execution environment for annotation and review. It keeps ontology, item state, instructions, comments, issues, navigation, and workflow actions consistent while loading the native editor required by the active data.
Use this area when: you are training annotators or reviewers, troubleshooting missing actions, or designing a consistent multimodal operating flow.
Choose an annotation workspace
Select the guide that matches the data and decision you need to produce.
How this area fits into production
The center canvas changes by modality; ontology, item status, contextual collaboration, navigation, and workflow actions remain part of the same operating shell.
What this area controls
Across modalities, Unitlab keeps a recognizable operating model:
top-center previous/next work-item navigation;
active class or annotation type;
Multiview mode and layout controls;
object/class or event/entity inspection;
item properties;
object properties and relations;
comments;
tags;
appearance and visibility controls;
save and version-history controls;
workflow actions appropriate to the active stage;
project instructions and issue context.
The active native editor supplies the modality-specific toolbar, timeline, player, page controls, and inspector content. The surrounding Workbench stays stable when navigation crosses data families.
Annotation keyboard shortcuts
Press H inside the active annotation panel to open the context-aware Annotation Shortcuts dialog. It groups the shortcuts available for the current data family into Annotation Tools, Actions, and Views. Only the active Workbench panel receives shortcuts; passive Multiview panels remain read-only.
Common actions and view controls
H
Show shortcuts
Opens the shortcut dialog for the active modality
Ctrl/Cmd + Z
Undo
Reverses the last annotation edit
Ctrl/Cmd + Y or Ctrl/Cmd + Shift + Z
Redo
Reapplies the last reversed edit
Delete/Backspace
Delete selected
Removes the currently selected annotation
Ctrl/Cmd + C
Copy
Copies the selected annotation; native text copy takes priority when text is selected
Ctrl/Cmd + X
Cut
Cuts the selected annotation; native text editing takes priority in text fields
Ctrl/Cmd + V
Paste
Pastes the copied annotation into the active annotation context
1–9
Select class
Activates the project class assigned to that numeric hotkey
+ / − / 0
Zoom in / zoom out / reset
Changes or resets the active viewer zoom
Shift + H
Home
Returns from the annotation workspace to the project/home context
R / K
Review / reject in compatible legacy contexts
Workflow-managed items use the explicit stage actions in the Workbench header, which guard these status shortcuts
Visual annotation tools
V
Pan/select/reposition
Image, video, medical, document; also Pan mode in text
B
Bounding Box
Image, video, medical, document
N
Cuboid
Image, video, document
F
Brush
Image, video, medical, document
E
Eraser
Image, video, medical, document
P
Polygon
Image, video, medical, document
L
Polyline
Image, video, document
J
Skeleton
Image, video, document
U
Keypoint
Image, video, document
A
Add polygon point
Adds a point while editing polygon geometry
M
Magic Touch
Image, video, medical, document; Shift + Click removes from the assisted mask
S
Detect all objects
Image and video for an active box, polygon, mask, or cuboid class
T
Toggle crosshair
Image, video, medical, document
C
Comment
Adds an annotation comment
D
Select PDF Text
Document only; selects, copies, or converts embedded PDF text into annotations
[ / ]
Decrease/increase brush size
Image, video, medical, document
Esc
Finish the active drawing operation
Completes the current segmentation/drawing interaction and returns to a stable editing state
Object ordering
W
Bring selected annotation to front
O
Bring selected annotation one level forward
I
Send selected annotation one level backward
Q
Send selected annotation to back
These ordering commands apply to overlapping canvas annotations. The same actions appear in the object right-click menu and become unavailable when the selected object is already at the relevant edge of the stack.
Navigation and playback
Image, audio, text
← / →
Previous/next work item
Document
← / →
Previous/next PDF page
Document
Shift + ← / Shift + →
Previous/next PDF document
Video, medical
← / →
Previous/next frame or slice
Video, medical
Shift + ← / Shift + →
Previous/next video or medical work item
Video, medical, audio
Space
Play/pause
Audio
↑ / ↓
Volume up/down
Audio
Alt + → / Alt + ←
Increase/decrease playback speed
Audio
L
Toggle loop
Audio
P
Toggle autoplay
Audio
S
Toggle spectrogram
Audio
T
Toggle timeline
Audio
Ctrl/Cmd + O / Ctrl/Cmd + I
Zoom waveform in/out
Text
T / R / C
Entity mode / Relation mode / Comment tool
Shortcut meanings are modality-aware. For example, T is Crosshair on a visual canvas, Entity mode in text, and Timeline visibility in audio; R is the Relation tool in text and a review action only in compatible non-workflow contexts.
Annotation View Settings
The View Settings panel controls how the active editor looks and responds without changing the source file. Available sections adapt to the resource family and Workbench mode.
Canvas / Rendering
Pixel Perfect
Preserves one-to-one pixel rendering for supported standalone image views; hidden where it does not apply, including medical and multi-panel layouts
Annotation Display
Display object names; Show properties & attributes; object-label font size; selected-object opacity; object-edge opacity
Controls labels and visual emphasis without changing saved geometry
Annotation Tools
Handle size; primitive keypoint sensitivity; show polyshape angles; ruler around cursor
Adjusts editing precision, control-point size, angle visibility, and local measurement guidance
Auto zoom
Auto zoom on timeline click; auto zoom on object-list click
Centers and enlarges the selected annotation when the corresponding navigation action is used
Image Adjustments
Color Map; Invert Image; Brightness; Contrast; Image Saturation
Changes the inspection view only; source-image properties remain unchanged
Video
Default annotation length; Jump frames
Sets the initial temporal span for a new annotation and the number of frames used by jump navigation
Hounsfield unit presets
Built-in preset selection; custom preset name; Save W/L; delete custom preset
Applies and stores medical window/level presets
3D Viewer Settings
Threshold; Opacity
Controls the medical 3D rendering
Projection (MIP)
Single slice, MIP (max), MinIP (min), Average; slab thickness
Controls multi-slice projection when a medical volume is available
Windows Levels
VOI LUT mode; histogram; window-width/level range; reset; Tab + ←/→ for width and Tab + ↑/↓ for level
Controls the displayed intensity range for medical-image inspection
Settings persist as annotation-view preferences. They alter rendering, navigation, or editing ergonomics; they do not rewrite the uploaded media.
Work-item status
Item status is derived from the item’s current workflow stage, not maintained as an unrelated manual field. User-facing status buckets include:
New;
In annotation;
In Review;
AI Review where applicable;
Processing;
Complete;
Archived;
Error.
Task-level status can further show Reopened, Skipped, Pending, Dispatched, Running, Paused, Succeeded, or Failed. An Invalid sub-state appears when the latest saved history fails required-property or value validation. Validation is non-blocking: the save succeeds, the item is marked for correction, and the workflow can route it appropriately.
7. Multiview Workbench UX
Multiview is the default project annotation experience for all six data families. It is a persistent workspace containing the project header, work-item navigation, mode/layout selector, resizable panel grid, one active editor, and one or more passive inspection panels.
Two modes
Current file
Multiple views of the same datasource
One active editor; sibling panels mirror its changes in real time
1×1
Multiple files
Neighboring work items from the current queue/filter scope
One selected panel is editable; other items remain passive previews
1×3
Layouts range from 1×1 to 4×4. Users can resize panel boundaries, fullscreen a panel, and switch modes from the Workbench header. Mode, layout, and panel sizes persist for the user.
Active and passive panels
Only the active panel can mutate annotations. It receives the full native editor: tools, hotkeys, selection, object/event/entity editing, player or page controls, comments, classes, properties, history, and workflow actions.
Passive panels can show media, annotations, labels, pages, frames, waveforms, text, or medical projections. In Current file mode they receive the active panel’s live annotation changes, but they cannot originate edits, change the active selection, save, control playback, change a PDF page, edit text entities, or alter waveform regions.
When the user activates a passive panel:
Unitlab visually selects it immediately.
Any in-progress save in the outgoing panel is allowed to settle.
Unsaved changes are saved or safely snapshotted.
The outgoing panel becomes passive and pauses modality-specific playback.
The incoming native editor loads and restores its panel state.
The route updates only after the editor is ready.
If hydration fails, Unitlab restores the previous active panel instead of blanking the workspace.
Current file flow
The user opens a work item from a dataset, Task Queue, Batch Queue detail, filtered grid, or direct link.
Unitlab creates multiple panel sessions for the same datasource without duplicating data or history.
One panel is active; the rest are read-only siblings.
Active edits are broadcast to siblings in real time.
The user can activate another panel to work from a different view, frame, page, or zoom state.
Saving refreshes the shared history and updates every sibling to the persisted result.
Current-file examples:
Image: compare the same image at different zoom or inspection states.
Video: inspect different frames of the same video while sharing annotations and downloaded frames.
Audio: inspect different time regions while one waveform editor remains authoritative.
Text: compare different windows of the same text while entity/relation changes remain synchronized.
Document: compare different PDF pages without confusing page changes with work-item navigation.
Medical: assign Axial, Sagittal, Coronal, and 3D views to separate slots with synchronized annotation state.
Multiple files flow
The user selects Multiple files and a layout.
Unitlab fills the grid with the active item and neighboring items from the current visible set.
The visible set preserves queue, upload-session, archive, search, status, class, and assignment filters.
The user activates any ready panel.
If the item belongs to another data family, the correct editor loads within the same Workbench shell.
Previous/next navigation continues through the filtered work-item sequence.
Empty tail slots and inaccessible items appear as panel-level states rather than replacing the whole page with an error.
This mode supports mixed review—for example an image, video, PDF, and audio item in one 2×2 layout—while guaranteeing that only the selected panel is editable.
Navigation hierarchy
Unitlab maintains three distinct navigation levels:
Top-center previous/next: changes the project work item and can cross data families or move between loose items and Data Groups.
Panel activation: changes which visible panel is editable without leaving the Workbench.
Within-item media navigation: changes a video frame, audio time region, text window, medical slice/view, or PDF page inside the current work item.
Keeping these levels separate is essential for predictable UX. A PDF page change must never advance to another datasource, and a medical slice change must never appear as another project item.
Grouped Workbench
A Data Group opens as one grouped Workbench whose layout is fixed by the Auto-Grouping builder. The header shows the group layout rather than the general mode/layout selector. Activating a tile never tears down the group route.
The project’s unified previous/next sequence treats each group as one work unit and excludes its member tiles from the loose-item sequence. Grouped saves remain attributable to the group.
Start with the right page
Learn universal controls
Start with keyboard shortcuts, view settings, item state, and workflow actions.
Annotate one modality
Continue to Image, Video, Text, Document & PDF, Audio, or Medical Annotation.
Work across files
Use Multimodal Annotations and the Multiview Workbench.
Improve speed
Use AI-assisted annotation only inside the same quality contract.
Operating boundary
Saving annotation state is different from routing the task to another stage.
Viewer navigation is different from project-item navigation.
A missing action can be caused by role, stage, selection, resource state, or configuration.
A production-ready handoff
An annotator can identify the active item, ontology, workflow stage, save state, navigation scope, and next valid action without leaving the task.
Explore related Unitlab capabilities: enterprise data annotation workflows · multimodal data annotation