Annotation Drawings

An annotation drawing consists of one or more arrows, ellipses and freeform lines plus an optional label that are displayed directly on the video to annotate a tracker experiment.

1. Drawing Control

Click the pencil on the drawing button (near the right end of the toolbar) to open the Drawing Control and enable drawing. When the Drawing Control is open you can draw arrows, ellipses and freeform lines on the video by dragging the mouse (pencil cursor). In the Drawing Control, enter the label text and choose the color and other properties of the drawing. Labels are initially drawn in the center of the current viewport; drag them with the mouse to move. When done drawing simply close the Drawing Control.

Fig. 1 Drawing Control with a blank drawing.

2. Drawing properties

Every drawing has the following properties:

1. A start and end frame that define its visibility. By default the start frame is the current video frame when the drawing is created and the end frame is the last frame in the video.
2. An optional label with a settable font size.
3. A color that applies to both the shapes and label. Click a color box to select the color.
4. A style that can be heavy or light. Heavy drawings have wide lines and bold fonts.

Fig. 2 Color and style options. Labels are automatically truncated in the drawing dropdown as shown.

3. Creating and deleting drawings

When the Drawing Control is first opened a new blank drawing will be automatically created and displayed as shown in Fig. 1. The drawing is identified by its label and frame range.

Click the New button in the Drawing Control to create additional drawings. Click the Delete button to delete the current drawing or the Clear All button to delete all drawings.

4. Lines

Draw lines by dragging the mouse (pencil cursor) directly on the video, not in the Drawing Control window.

5. Labels

Create a label by entering text into the label field. New labels are positioned in the center of the current view. Drag the label with the mouse (while in drawing mode) to reposition it.

Fig. 3 Drag a label when you see the hand cursor to reposition it.

6. Visibility

To hide all drawings, click the right side of the drawing button (small arrow) and uncheck the Drawings Visible checkbox. Note that a drawing is visible only when the Drawings Visible checkbox is selected and the current frame number is within the drawing's frame range.

Fig. 4 Access the Drawings Visible checkbox by clicking the small arrow next to the pencil.

7. Undo/Redo

The undo and redo buttons on the right side of the Drawing Control enable you to undo and redo drawing lines, changing text, deleting drawings and clearing all drawings.