Controlling reading of a head-mounted sensor according to facial expressions

Abstract

Disclosed herein are systems and methods for tracking facial expressions efficiently. In one embodiment, a system includes a non-contact head-mounted electro-optical sensor (e.g., an inward-facing head-mounted camera), which measures reflections from a region on a user's head, which are indicative of facial expressions of the user. The system also includes a computer that detects, based on the reflections, a type of facial expression expressed by the user, which belongs to a group comprising neutral facial expressions and non-neutral facial expressions. The computer uses this detection to determine how to proceed to read the electro-optical sensor: the computer reads the electro-optical sensor at a first average bitrate (b) when the user expresses a facial expression from among the neutral facial expressions, and reads the electro-optical sensor at a second average bitrate (b) when the user expresses a facial expression from among the non-neutral facial expressions, where b>b.