Knowledge Base

Export (Detailed Log Only)

Subject Characteristics

With this option selected, three extra columns are added to the Detailed log: Gender (male/female), Age (an estimation of the test person's age) and Glasses (Yes/No).

See Circumplex Model of Affect in FaceReader's output

Participant Name And Analysis Index

The name of the participant and the name of the analysis.

Model Quality

The model quality is indicated by a value between 0 and 1.

See one of the following:

• Step 3 in Manual procedure image analysis
• Step 3 in Manual procedure video and camera analysis in Analyze facial expressions

Empty Data

Choose how the following values are exported to the export files:

• Log value when the face could not be found – The term when FaceReader cannot find a face
  Default: FIND-FAILED.
• Log value when the model fit failed – The term when FaceReader finds a face but cannot create a model of it.
  Default: FIT-FAILED.
• Log value for when an item is unknown – The term when FaceReader finds a face and can create a model, but cannot determine the facial expression.
  Default: UNKNOWN

Visualization

Camera

Automatically Clear Results After 1 Minute (For Demonstration Only)

Select this option when giving a demonstration, to make sure that FaceReader can run for a long time.

Default: Not selected.

Video

Repeat Video (For Demonstrations Only)

This option is for demonstration purposes only. If you select this option your video is played continuously.

Default: Not selected.

Advanced Options

Face Modeling

Minimum Model Quality

The minimum model quality required for a model to be valid.

Accepted values: 0 (low quality) - 1 (high quality).

Default value: 0.5 (this is the hatched line that you see in the middle of the Model quality bar).

Gaze Tracking

Angular Speed Threshold

This threshold is used to distinguish between saccades (faster than the threshold) and fixations (slower than the threshold).

Head Orientation

The test person should stand or sit and look frontally into the camera, an angle of 30° (in both directions, yaw and pitch) is accepted by default. If the angle is bigger than this threshold, the face model will be rejected. You can increase or decrease the thresholds to accept face models of lower/higher quality, respectively.

• Maximum allowed pitch angle — If the pitch angle is higher than this threshold, the face model will be rejected.
  Default value: 30 degrees.
• Maximum allowed yaw angle — If the yaw angle is higher than this threshold, the face model will be rejected.
  Default value: 30 degrees.
• Minimum allowed pitch angle — If the pitch angle is lower than this threshold, the face model will be rejected.
  Default value: -30 degrees.
• Minimum allowed yaw angle — If the yaw angle is lower than this threshold, the face model will be rejected.
  Default value: -30 degrees.

Heart Rate

Heart Rate Variability Period

The minimum time that is needed to calculate heart rate variability.

Accepted values: 1-60 minutes. Default: 5 minutes.

See also Calibration in The Vital Signs Module.

Size Of Interest

You can set the Size of Interest by clicking the up and down arrows for the Minimum face fraction and/or the Maximum face fraction.

Minimum Face Fraction

Minimum fraction of the face surface relative to the entire image surface.

Accepted values: 0.01 - 1. Default: 0.11.

Maximum Face Fraction

Maximum fraction of the face surface relative to the entire image surface.

Accepted values: 0.01 - 1. Default: 0.80.

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