Abstract: A gaze tracking system comprising a pupil detection unit operable to detect the location of a pupil in one or more images captured of one or both a user's eyes, a confidence value determination unit operable to determine a confidence value in dependence upon the identified pupil position, the confidence value indicating an expected reliability of the detection of the pupil location, and a processing unit operable to generate, in dependence upon the determined confidence value, one or more outputs to cause the user to modify their pupil location to a location with a higher determined confidence value.

Abstract: A gaze tracking system comprising one or more cameras operable to capture one or more images of a side view of one or both of a user's eyes, a cornea identification unit operable to identify the location and size of a cornea in one or more of the captured images, a gaze detection unit operable to determine a direction of the user's gaze in dependence upon the identified location of the cornea in the one or more captured images.

Abstract: A system for generating images for display, the system comprising a content identification unit operable to identify content to be displayed, an overlay identification unit operable to identify an overlay to be applied to at least a portion of the content to be displayed, a rasterization rate determining unit operable to determine, in dependence upon the identified overlay, a rasterization rate to be applied to each of two or more areas of at least a frame of the content to be displayed, a rendering unit operable to render the content to be displayed in accordance with the determined rasterization rates, and an overlay applying unit operable to generate an image by applying the overlay to the rendered image.

Abstract: A method of rendering image frames for a videogame comprises the steps of, for one or more predetermined features of a virtual environment of a videogame, setting a respective per-frame movement distance threshold; calculating a respective minimum frame rate at which movement of the or each predetermined features of the virtual environment of the videogame between successive image frames remains within the respective movement distance threshold; detecting whether the current frame rate is below one or more of the respective minimum frame rates; and if so, reducing a rendering resolution used during rendering of one or more subsequent image frames to increase the frame rate above one or more of the minimum frame rates.