2D Bbox or Rectangle

A Rectangle or 2D Bounding Box (BBox) is a rectangular annotation tool used to enclose and label objects within a 2D image. It is defined by opposite corners, creating a box that contains the object of interest. This is one of the simplest and fastest annotation methods for objects with clear boundaries.

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Settings

2D Bbox Truncation

Controls how rectangles behave when they extend beyond the image boundaries.

• Toggle ON: Rectangles automatically truncate by snapping back to the image edge when they extend beyond it. This ensures all annotations remain within the visible image area.

• Toggle OFF: Rectangle dimensions remain unchanged even if part of the rectangle lies outside the image boundaries. The full bounding box is preserved in the data.

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Landmarking in Bbox

Enables landmark annotation within rectangles for this class.

• Toggle ON: A vertical line appears at the center of each rectangle, allowing annotators to mark a specific keypoint within the bounding box.

Use cases: Marking the center of a vehicle, identifying the tip of an object, or placing reference points for alignment.

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Edge Length Constraint

Define minimum and maximum dimension limits for rectangles belonging to this class. This helps maintain annotation quality by preventing unrealistic or erroneous bounding box sizes.

• Minimum: Set the smallest allowed width and height (e.g., 10 pixels × 10 pixels)

• Maximum: Set the largest allowed width and height (e.g., 500 pixels × 500 pixels)

Example: For a "Pedestrian" class, you might set a minimum of 20×40 pixels and a maximum of 150×300 pixels based on expected object sizes in your images.

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Create Rectangle

1. Click the '+' icon next to the class you want to annotate from the class list.

2. Select 'Rectangle' from the drawing tool list.

3. The cursor pointer shows a red circle marker while hovering over the image.

4. Left-click to define opposite corners of the rectangle. A red box preview appears as you move the mouse. Click at the appropriate location to confirm the annotation.

5. Enter the annotation details.

6. The saved instance will appear in the class list with a 2D icon next to the instance name, indicating it was created in the image sensor.

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Modify Rectangle

To modify an existing rectangle:

• Resize two edges: Select and drag a corner vertex to modify two adjacent edges simultaneously.

• Resize one edge: Select and drag an edge to modify only that edge.

Landmark Within Rectangle

If enabled during recipe creation, rectangles can include a keypoint annotation. When you create a rectangle, a keypoint automatically appears at the center. You can then reposition the keypoint to the desired location within the rectangle.

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Copy and Paste Rectangle

Rectangles can be copied and pasted to another image sensor where they don't currently exist using Ctrl+C to copy and Ctrl+V to paste. When pasting, an annotation detail prompt will appear for you to enter information. By default, the pasted rectangle will share the same Instance ID as the original copied rectangle.