Examples of facial expressions with and without masks.

(A) To satisfy the copyright policies, in this Figure, we use artificially generated faces from the website https://generated.photos, which provides unique facial portraits that do not exist. Reprinted from https://generated.photos under a CC BY license, with permission from the website’s owner, original copyright 2024. The images of the faces are examples for illustrative purposes only and are different from the original images used in the study. Therefore, these are irrelevant to Table 1. In the experiments, we used real face images from the FER2013 [2] dataset. (B) The FER2013 [2] and FERPlus [3] datasets did not contain either images or labels for the masked faces. Therefore, the original images have been processed using artificial face masks that were synthesized, as described in the Methods section.