UIBVFED Physical Sates

A common point in most of the reviewed literature, is that it is necessary to transcend mere facial expression recognition towards a more comprehensive understanding of human emotions in diverse scenarios. In this context, physical states like pain, effort and sleepiness, involve facial muscle activity, shaping expressions that aren’t straightforwardly linked to emotions.

We have categorized 16 facial expressions based on physical states from the description given by Gary Faigin in 'The Artist’s Complete Guide to Facial Expression,' Watson-Guptill, 2012.

These expressions are:

Expression

Description

Pain 1

Extreme pain. The face undergoes spasms in an intense contraction

Pain 2

Sudden, unexpected pain, often expressed with a shout

Exertion 1

Similar to expressions of pain. The eyes almost never clench as tightly and often will remain open, somewhat narrowed

Exertion 2

Lip pressing, equally common responses to physical effort

Drowsiness 1

The levator palpebrae relaxes. The eyes attempt to stay open with the action of the frontal muscle lifting the brows

Drowsiness 2

Eyelids droop, and vision becomes blurred. Successive blinking

Yawning 1

General clenching of facial muscles. The mouth opens as wide as possible

Yawning 2

Brows as often lowered as raised in yawn. Eyes partly shut in a squint.

Singing 1

Only two of the multiple mouth positions are illustrated. Only involves the lower half of the face. Illustrates the singing of the sound "ah"

Singing 2

Many vowel sounds, sung and spoken, involve the action of the lip muscle that purses the lips. Illustrates the singing of the sound "eeeee"

Shouting

Usually accompanied by squinting. The lower lip becomes square downward, and the upper lip rises

Passion / Asleep

Slightly opened mouth and closed, relaxed eyes. The expression can have many possible interpretations such as sleeping, stupor, or sexual passion

Intensity / Attention

When not seen as anger, the combination of widened eyes and lowered brows is understood as intense concentration and interest

Brows up

The brow lift is one of the most common actions in conversational expressions. It corresponds to surprise, emphasis, greeting, etc.

Shock

Closely related to the emotion of fear. It can express distress

Facial shrug

The facial equivalent of shrugging the shoulders. It is a gesture of resignation.

The modeled physical states have been defined over 100 avatars created using the Autodesk Character Generator tool, deforming the facial meshes according to the muscular activity described by Faigin. The images have been generated within a Unity 3D environment, similar to how UIBVFED has been developed.

The result is a new dataset, UIBVFED Physical States, with 100 synthetic avatars, each reproducing the 16 expressions related to the considered physical states.

This novel dataset aims to address and alleviate the issues associated with biased estimations in FER tasks. By including a comprehensive range of physical states, the UIBVFED Physical States dataset facilitates  more inclusive and accurate training of recognition systems, enhancing their robustness and applicability across diverse scenarios.