Annotation Settings

Annotation settings control the behavior of the labeling interface — playback speed, navigation step size, and auto-save behavior. Adjust these settings to match your data characteristics and personal workflow preferences.

Overview

Settings are applied at the project level and affect all annotation sessions within that project. Some settings can be overridden at the dataset level for cases where individual datasets have different recording parameters (e.g., different frame rates).

Changes to settings take effect immediately — no need to reload the page or restart the annotation session.

FPS (Playback Speed)

The FPS setting controls how fast the trajectory plays back when you press Play. It determines the number of CSV frames displayed per second during animated playback.

• Default: 10 FPS.
• Range: 1–60 FPS.
• Effect: Higher values produce faster playback; lower values make it easier to observe individual frames during animation.

The FPS value also controls video synchronization. The system uses this value to map CSV frame indices to video timestamps, so setting it correctly is important for accurate video alignment.

Step Size

The step size determines how many frames the viewer advances (or retreats) with each navigation action. It affects arrow key navigation and Auto-Advance mode.

• Default: 1 frame per step.
• Common values: 1, 5, 10, or any custom integer.
• Use case: Set to 1 for precise frame-by-frame annotation. Increase for quick scanning through long trajectories where you only need to sample every Nth frame.

Changing the step size does not affect existing annotations. It only changes how the navigation controls behave going forward.

Auto-Save

Auto-save periodically saves your annotation progress in the background without requiring a manual save action. This protects against data loss from browser crashes, accidental navigation, or network interruptions.

• Default: Enabled.
• Behavior: When enabled, annotations are saved automatically at a regular interval. A brief save indicator appears in the toolbar when a save occurs.
• Manual save: You can always save manually at any time with Ctrl+S, regardless of whether auto-save is enabled.

Per-Dataset Overrides

While settings are defined at the project level, certain settings can be overridden for individual datasets. This is useful when datasets within the same project have different characteristics.

Overridable settings include:

• FPS — Different datasets may have been recorded at different frame rates.
• Video offset — Each dataset may have a different alignment between the CSV and the video recording.

Dataset-level overrides take precedence over project-level settings. If no override is set, the project default is used.

Accessing Settings

Settings are accessible from two places:

• Project settings — The Settings tab in your project configuration. Changes here set the defaults for all datasets in the project.
• Annotation toolbar — Quick-access controls for FPS and step size are available directly in the labeling interface toolbar, so you can adjust them without leaving the annotation view.

Settings Reference