TTP: Authentication Using Face Image

Note:  New instances/applications of TTP are not currently being supported.

Overview

Biometric authentication is how a portal device verifies an Employee via biometric information contained in fingerprints or face images. In the case of face images, verification is acquired through analyzing various elements of the face image and comparing them to all enrolled composite face images. Face images are captured through a webcam's live stream.

The Login screen will display the biometric face image if biometric match is required and/or if the default authentication method is face.

How strict the authentication process will be is determined in the Biometric Tolerances screen in WinTeam. The Biometric Tolerance setting for each device is selected in the Device Settings screen in WinTeam.

Three Biometric Tolerance settings will be available for users to select: Medium, Medium-High and High. Users can also create their own Biometric Tolerance settings group, if necessary.

Note:  Ensure the TTP device is not displayed by direct sunlight. If the sun reflects into the device or onto the employee face it can interfere with the facial recognition process.

For details on these settings for authentication via face image, review the definitions below.

Key Functionality

The following are common terms and settings used when dealing with biometric authentication.

This value is the number of consecutive frames the stream must contain in order for enrollment to take place successfully. (Default: 10; before adjusting this value, consult a TEAM representative for assistance.)

This value determines how similar to a human face the image must be (how confident the software is that the image is actually a face). The higher the value, the stricter the software will be in determining the "face" attribute.

This value determines how good the face image must be in order to extract facial features from it. The higher the value, the better quality the face image must have in order for features to be extracted from it. (Range: 0-255; Default: 128)

This value is the number of images that must be used when generalizing face images into a composite image.

This value determines how strictly the software will check the live stream for a real face. The higher the value, the more strict the software will be in determining whether the face is real. (Range: 0-100; Default: 20)

During the authentication process, when matching (or comparing) a captured face image and a stored face image (from enrollment), this value is the number of times the software will attempt to match the captured image with a stored image in order to authenticate.

When using Liveness Detection, a stream of consecutive face images captured from the video stream of the webcam is required. This value is the number of consecutive frames the stream must contain in order for matching to take place during authentication. (Minimum: 10; Default: 10

The False Accept Rate is the average number of times out of 100 that the software will match a face image with the wrong person. The higher this value, the lower the FAR will be; however, the number of times the software erroneously rejects a face image will increase as well.

This value determines the maximum distance between the eyes an image can have in order to be captured successfully. Distances outside the Minimal/Maximal Interocular Distance range will be ignored and face images will not be captured. (Default: 4,000; before changing this value, contact a TEAM Representative for assistance.)

If Liveness Detection is used, this value must be 1.

This value determines the maximum degree of rotation a face can have in order to be properly matched. (Default: 45)

This value determines the minimum distance between the eyes an image must have in order to be captured successfully. (Default: 40; before changing this value, contact a TEAM Representative for assistance.)

When this option is enabled, the software will check to see if the face images are extracted from a live image stream. (This option should never be disabled.)