Skip to content

Quick Annotation Tool Module Guide

The Quick Annotation Tool is a browser-based painting interface for creating ground-truth segmentation masks on TIFF image stacks. These annotations serve as training data for U-Net segmentation models or can be used directly for mesh generation.

For a conceptual overview, see Annotation.

Annotation module showing the painting interface with toolbarThe Annotation Tool interface with canvas, toolbar, and class management


Quick Start

  1. Launch module — Click "Quick Annotation Tool" from the workspace hub
  2. Select an image — Choose a TIFF stack to annotate (new, resume, or edit)
  3. Paint annotations — Use the brush tool to label regions of interest
  4. Navigate slices — Use arrow keys or buttons to move through the stack
  5. Save your work — Click "Save Progress" or "Create Annotation" when done

Step-by-Step Guide

Step 1: Data Selection

Choose your source image and annotation mode.

Step 1 showing file selection optionsStep 1 with annotation mode selection and file chooser

Input Options

ModeDescriptionWhen to Use
New AnnotationStart fresh on a raw TIFF imageCreating annotations from scratch
ResumeContinue an unfinished annotationReturning to work in progress
EditModify an existing completed annotationRefining previous work

File Requirements

  • Format: Multi-page TIFF (.tif or .tiff)
  • Bit Depth: 8-bit or 16-bit grayscale
  • Channels: Single channel (grayscale)

Tip: Large files work but may affect performance. Consider splitting very large stacks.

For more details, see Source Image.

Click "Next" to proceed to the annotation interface.


Step 2: Annotation Interface

The annotation interface provides all tools needed to paint segmentation masks.

Step 2 interface with all areas labeledAnnotation interface with canvas, toolbar, and control areas

Interface Layout

AreaLocationPurpose
CanvasCenterMain painting area showing current slice
ToolbarRight sideTools, brush size, history, and class management
Control BarAbove canvasSlice navigation and zoom controls
Status BarBelow canvasCursor coordinates and image dimensions

Tools

Brush Tool

Paint annotations with the currently selected class.

PropertyValue
ShortcutB
BehaviorClick and drag to paint continuous strokes
ColorUses the active class color

Eraser Tool

Remove annotations by painting with background (transparent).

PropertyValue
ShortcutE
BehaviorClick and drag to erase
EffectSets pixels to background (class 0)

Tip: The eraser respects class visibility—it only erases classes that are currently visible.

For more details, see Annotation Tools.


Brush Size

Control the size of your brush and eraser.

Brush size slider in toolbarBrush size slider in the toolbar with pixel size display

ControlAction
SliderDrag to adjust size (1-50 pixels)
[ keyDecrease size by 5 pixels
] keyIncrease size by 5 pixels

The current size is displayed next to the slider (e.g., "10px").

For more details, see Brush Size.


Class Management

Manage the classes (labels) you're annotating.

Class panel showing multiple classesClass management panel with color swatches and visibility toggles

Class List

Each class shows:

  • Color swatch — The class color (auto-assigned)
  • Name — Class label (e.g., "Class 1")
  • Visibility toggle — Show/hide this class on canvas
  • Delete button — Remove class and all its pixels

Class Actions

ActionHow
Add classClick the "+" button in the Classes header
Select classClick on a class to make it active for painting
Toggle visibilityClick the eye icon to show/hide
Delete classClick the × button (removes all pixels with that class)

Note: Colors are automatically assigned using a color distribution algorithm that ensures good visual separation between classes.

For more details, see Annotation Classes.


Canvas Controls

Zoom

ControlAction
+ buttonZoom in (125% of current)
− buttonZoom out (80% of current)
Fit button (⊡)Auto-fit image to view
1:1 buttonReset to 100% zoom
Mouse wheelScroll to zoom (toward cursor)

Zoom range: 10% to 1000%

Pan

MethodHow
Right-click + dragPan the canvas
Middle-click + dragPan the canvas
Space + left-click + dragHold Space, then drag to pan

Tip: When zoomed in, the cursor changes to a hand icon to indicate you can pan.


Slice Navigation

Navigate through the 3D stack to annotate each slice.

Slice navigation controlsSlice navigation with previous/next buttons and position indicator

ControlAction
◀ buttonGo to previous slice
▶ buttonGo to next slice
Left arrow keyPrevious slice
Right arrow keyNext slice
Slice indicatorShows current position (e.g., "12 / 64")

Note: Each slice has its own independent undo/redo history.


History (Undo/Redo)

Undo and redo your painting actions on the current slice.

ActionShortcutButton
UndoCtrl+Z (Cmd+Z on Mac)↶ button
RedoCtrl+Y or Ctrl+Shift+Z↷ button
  • History is per-slice — each slice maintains its own history
  • Maximum 20 undo states per slice
  • Buttons are disabled when no history is available

Saving Your Work

Save Progress

Save your work-in-progress to continue later.

  • Button: "Save Progress" (in header)
  • Status: Marked as "in progress"
  • Location: Saved to unfinished_annotations/ folder
  • Resume: Select "Resume" in Step 1 to continue

Create Annotation

Finalize your annotation for use in training or mesh generation.

  • Button: "Create Annotation" (in header)
  • Status: Marked as "complete"
  • Location: Saved to annotations/ folder
  • Use: Ready for Segmentation training or Mesh generation

Autosave

Automatic saving protects against data loss.

SettingDefault
EnabledYes (toggle in toolbar)
IntervalEvery 2 minutes
ConditionOnly saves if changes exist

Tip: Even with autosave enabled, remember to click "Create Annotation" when you're finished to mark the annotation as complete.


Keyboard Shortcuts

ShortcutAction
BSwitch to brush tool
ESwitch to eraser tool
[Decrease brush size
]Increase brush size
Ctrl+ZUndo
Ctrl+YRedo
Left ArrowPrevious slice
Right ArrowNext slice
Space + DragPan canvas
Mouse WheelZoom in/out

Output Files

FileDescriptionLocation
annotation.tifMulti-page TIFF with class labels as pixel valuesannotations/ or unfinished_annotations/
annotation.jsonMetadata including class definitions and source infoSame as TIFF

TIFF Format:

  • 8-bit grayscale
  • Pixel value = class ID (0 = background, 1+ = classes)
  • One page per slice in the stack

Troubleshooting

IssueCauseSolution
Can't paint on canvasWrong tool or no class selectedPress B for brush, ensure a class is selected
Brush not visibleClass visibility turned offClick the eye icon to show the active class
Undo not workingNo actions to undo on this sliceUndo history is per-slice; may need to check other slices
Changes not savingNetwork error or autosave disabledClick "Save Progress" manually; check console for errors
Image not loadingFile too large or invalid formatTry a smaller file or check TIFF format
Lost my workBrowser closed without savingCheck unfinished_annotations/ for autosaved progress

Module Overview:

Tools & Controls:

Data:

Part of DFG Priority Programme SPP2332 "Physics of Parasitism"