Facial recognition

An example method includes receiving first and second images of a face of a user, where one or both images have been granted a match by facial recognition. The method includes identifying at least one facial landmark in the first image and at least one corresponding facial landmark in the second image, and extracting a first sub-image from the first image, where the first sub-image includes a representation of the at least one facial landmark. The method includes extracting a second sub-image from the second image, where the second sub-image includes a representation of the at least one corresponding facial landmark, detecting a facial gesture by determining whether a sufficient difference exists between the second sub-image and first sub-image to indicate the facial gesture, and determining, based on detecting the facial gesture, whether to deny authentication to the user with respect to accessing functionalities controlled by the computing device.