Fast wake-up in a gaze tracking system

Abstract

A gaze tracking system, leaving a low power mode in response to an activation signal, initial burst of eye pictures in short time by restricting the image area of a sensor, purpose of enabling an increased frame rate. Subsequent eye pictures are captured at le rate. The first gaze point value is computed memorylessly based on the initial burst res and no additional imagery, while subsequent values may be computed recursively to account previous gaze point values or information from previous eye pictures. The restriction of the image area may be guided by a preliminary overview picture captured using the different sensor. From the gaze point values, the system may derive a control signal to a computer device with a visual display.

What is claimed is: 
     
         1 . A method for initiating control of a gaze tracking system from a low power mode, wherein the method comprises:
 in response to a gaze tracking activation signal, leaving a low power mode of the gaze tracking system;   capturing, at a first frame rate, a first plurality of pictures of at least a portion of a head of a viewer using a first restricted region of a light-sensitive surface;   determining, based on only the first plurality of pictures a first gaze point value of the viewer;   providing a first control signal to a computer device based on the first gaze point value;   capturing, at a second frame rate, lower than the first frame rate, a second plurality of pictures of at least a portion of the head of the viewer using a second region of the light-sensitive surface;   determining a second gaze point value of the viewer based on a picture from the second plurality of pictures and a picture from the first plurality of pictures; and   providing a second control signal to the computer device based on the second gaze point value.