Knowledge Base

Analyze Action Units

Aim

To quantify activation of Action Units in the test participant's face.

Prerequisite

Your FaceReader license includes the Action Unit Module.

Procedure

1. Choose File > Settings > Analysis options.
2. Under Optional Classifications, select Action units.

Action Unit Analysis is by default switched on if your FaceReader license includes the Action Unit Module.

Visualize Action Units

Aim

To display Action Units during or after the analysis.

Prerequisites

• Your FaceReader license includes the Action Unit Module or you have Baby FaceReader.
• You are running an analysis, or viewing the analysis afterwards.

Action Units in the Analysis Visualization Window

Click the Show action units button on the left side of this window. Action Units appear in the Analysis Visualization when the activity is Trace or higher. The colors under the name represent the activity of this Action Unit.

Action Unit Intensity

Select the Action Unit Intensity window from one of the visualization windows (see Manage analysis windows). It shows the intensity of 20 Action Units, divided into the classes Trace, Slight, Pronounced, Severe, and Max. These intensities are shown by consecutive letters from A to E. From the Action Units list, choose which ones to display.

Unilateral Action Units

Most Action Units are unilateral, that is, they can be visible in the left and/or right part of the face. To assess the intensity of the left and right part independently, select Options and then Split unilateral action units.

Please note that the unilateral Action Units have been evaluated only qualitatively, but not validated quantitatively. This is mainly due to unavailability of data: images of unilateral AU activation examples are rare in current datasets and hard to produce in general.

Continuous Value Bars

Select Options and then Show continuous value bars to visualize the intensity of the Action Units on a continuous scale.

Action Unit States

The intensity of the Action Units is displayed on the Timeline. Select Timeline in one of the windows (see Manage analysis windows). Choose which Action Units to display from the Action Units list on the toolbar. By default all Action Units are selected.

Note: To copy, save, or zoom in this window, see Common options in FaceReader's output.

Source: FaceReader 10 Reference Manual (Help), Noldus Information Technology