Abstract: A method of transmitting image data in an image display system, includes dividing the image data into framebuffers, and for each framebuffer: dividing the framebuffer into a number of vertical stripes, each stripe including one or more scanlines, dividing each vertical stripe into at least a first and a second block, each of the first and the second block comprising pixel data to be displayed in an area of the image, and storing first pixel data in the first block with a first resolution and second pixel data in the second block having a second resolution which is lower than the first resolution, transmitting the framebuffer over the digital display interface to a decoder unit, and unpacking the framebuffer, including upscaling the pixel data in the second block to compensate for the lower second resolution and optionally upscaling the pixel data in the first block.

Abstract: An encoder for encoding images includes at least one processor configured transform a given input pixel of an input image having (x, y) coordinates in a Cartesian coordinate system into a given transformed pixel of a transformed image having (?, ?) coordinates in a log-polar coordinate system, using a log-polar transformation in which a radial distance (?) of the given transformed pixel is a logarithm of a distance of the given input pixel from an origin in the Cartesian coordinate system, and an angular distance (?) of the given transformed pixel is a sum of an arctangent of a slope of a line connecting the given input pixel to the origin and a function of the radial distance, encode the transformed image, by employing a compression algorithm, into an encoded image, and send the encoded image to a display apparatus for subsequent decoding thereat.

Abstract: An encoder for encoding images includes at least one processor configured transform a given input pixel of an input image having (x, y) coordinates in a Cartesian coordinate system into a given transformed pixel of a transformed image having (?, ?) coordinates in a log-polar coordinate system, using a log-polar transformation in which a radial distance (? of the given transformed pixel is a logarithm of a distance of the given input pixel from an origin in the Cartesian coordinate system, and an angular distance (?) of the given transformed pixel is a sum of an arctangent of a slope of a line connecting the given input pixel to the origin and a function of the radial distance, encode the transformed image, by employing a compression algorithm, into an encoded image, and send the encoded image to a display apparatus for subsequent decoding thereat.

Abstract: An eye-tracking apparatus. At least one light source and a plurality of sensors are arranged at a periphery of a first surface of at least one lens. A frame is employed to hold the at least one lens. A processor coupled to the at least one light source and the plurality of sensors is configured to control the at least one light source to emit light towards the user's eye, control the plurality of sensors to sense reflections of the light off a surface of the user's eye, and process sensor data pertaining to the sensed reflections to determine a gaze direction of the user's eye.

Abstract: An encoding method and a decoding method. The encoding method includes generating curved image by creating projection of visual scene onto inner surface of imaginary 3D geometric shape that is curved in at least one dimension; dividing curved image into input portion and plurality of input rings; encoding input portion and input rings into first planar image and second planar image, respectively, such that input portion is stored into first planar image, and input rings are packed into corresponding rows of second planar image; and communicating, to display apparatus, first and second planar images and information indicative of sizes of input portion and input rings.

Abstract: An encoding method and a decoding method. The encoding method includes generating curved image by creating projection of visual scene onto inner surface of imaginary 3D geometric shape that is curved in at least one dimension; dividing curved image into input portion and plurality of input rings; encoding input portion and input rings into first planar image and second planar image, respectively, such that input portion is stored into first planar image, and input rings are packed into corresponding rows of second planar image; and communicating, to display apparatus, first and second planar images and information indicative of sizes of input portion and input rings.

Abstract: The transmitted information from a gaze tracker camera to a control unit of a VR/AR system can be controlled by an image signal processor (ISP) for use with a camera arranged to provide a stream of images of a moving part of an object in a VR or AR system to a gaze tracking function of the VR or AR system, the image signal processor being arranged to receive a signal from the gaze tracking function indicating at least one desired property of the images and to provide the stream of images to the gaze tracking function according to the signal. The ISP may be arranged to provide the image as either a full view of the image with reduced resolution or a limited part of the image with a second resolution which is high enough to enable detailed tracking of the object.

Abstract: A method of transmitting image data in an image display system, includes dividing the image data into framebuffers, and for each framebuffer: dividing the framebuffer into a number of vertical stripes, each stripe including one or more scanlines, dividing each vertical stripe into at least a first and a second block, each of the first and the second block comprising pixel data to be displayed in an area of the image, and storing first pixel data in the first block with a first resolution and second pixel data in the second block having a second resolution which is lower than the first resolution, transmitting the framebuffer over the digital display interface to a decoder unit, and unpacking the framebuffer, including upscaling the pixel data in the second block to compensate for the lower second resolution and optionally upscaling the pixel data in the first block.

Abstract: A tracking method for tracking a target in a VR/AR system having a tracker function for determining the position of the target, includes obtaining a stream of images of the target, placing two or more markers in determined positions on the target in the image said markers being arranged to follow the movement of the determined positions, detecting the movement of the markers between two images in the stream of images, if the detected movement is within a set of consistency criteria, determining the position of the target based on the detected movement, and if the detected movement is outside the set of consistency criteria, activating the tracker function. This reduces the computation power required for tracking.

Abstract: An AR system is arranged to display an image stream of an environment with one or more virtual objects, each virtual object being associated with a marker in the image stream. The AR system includes a tracking subsystem arranged to track a first pose of the marker in the image, and inform a frame rendering subsystem, which generates a rendering of the VR object and provides the rendering to the reprojecting subsystem together with information about the first pose of the marker and information identifying a set of pixels included in the VR image. The tracking subsystem further determines a second pose of the marker based on detected movement and informs the reprojecting subsystem about the second pose. The reprojecting subsystem renders an image frame including the image stream of the environment with the rendering of the VR object reprojected in dependence of the second pose.

Abstract: A display apparatus including means for tracking pose of user's head, light source(s) and processor configured to: process pose-tracking data to determine position, orientation, velocity and acceleration of head; predict viewpoint and view direction of user in extended-reality environment; determine region of extended-reality environment to be presented, based on viewpoint and view direction; determine sub-region(s) of region whose rendering information is to be derived from previous rendering information of corresponding sub-region(s) of previously-presented region of extended-reality environment; generate rendering information of sub-region(s) based on previous rendering information; send, to rendering server, information indicating remaining sub-regions required to be re-rendered and pose information indicating viewpoint and view direction; receive, from rendering server, rendering information of remaining sub-regions; merge rendering information of sub-region(s) and rendering information of remaining sub-

Abstract: A display apparatus including: light source(s); camera(s); and processor(s) configured to: display extended-reality image for presentation to user, whilst capturing eye image(s) of user's eyes; analyse eye image(s) to detect eye features; employ existing calibration model to determine gaze directions of user's eyes; determine gaze location of user; identify three-dimensional bounding box at gaze location within extended-reality environment, based on position and optical depth of gaze location; identify inlying pixels of extended-reality image lying within three-dimensional bounding box, based on optical depths of pixels in extended-reality image; compute probability of user focussing on given inlying pixel and generate probability distribution of probabilities computed for inlying pixels; identify at least one inlying pixel calibration target, based on probability distribution; and map position of calibration target to eye features, to update existing calibration model to generate new calibration model.

Abstract: A display apparatus including: light source(s); camera(s); and processor(s) configured to: display extended-reality image for presentation to user, whilst capturing eye image(s) of user's eyes; analyse eye image(s) to detect eye features; employ existing calibration model to determine gaze directions of user's eyes; determine gaze location of user; identify three-dimensional bounding box at gaze location within extended-reality environment, based on position and optical depth of gaze location; identify inlying pixels of extended-reality image lying within three-dimensional bounding box, based on optical depths of pixels in extended-reality image; compute probability of user focussing on given inlying pixel and generate probability distribution of probabilities computed for inlying pixels; identify at least one inlying pixel calibration target, based on probability distribution; and map position of calibration target to eye features, to update existing calibration model to generate new calibration model.

Abstract: Disocclusion in a VR/AR system may be handled by obtaining depth and color data for the disoccluded area from a 3D model of the imaged environment. The data may be obtained by raytracing and included in the image stream by the reprojecting subsystem.

Abstract: A gaze-tracking system for use in head-mounted display apparatus. The gaze-tracking system includes: illuminators; camera; and processor configured to: illuminate illuminators in sequential manner; control camera to capture eye images of user's eye during illumination of illuminators; identify reflection(s) of illuminator in eye image; determine extent of deformation in shape of reflection(s) with respect to shape of illuminator; determine extent of displacement in position of reflection(s) with respect to position of illuminator; compute user-specific score for illuminator based on extents of deformation and displacement; select illuminator(s) based on user-specific scores; illuminate illuminator(s); control camera to capture eye image of user's eye during illumination of illuminator(s); and detect gaze direction of user based upon relative position of pupil of user's eye with respect to reflections of illuminator(s) in eye image.

Abstract: A display apparatus including means for tracking pose of user's head, light source(s) and processor configured to: process pose-tracking data to determine position, orientation, velocity and acceleration of head; predict viewpoint and view direction of user in extended-reality environment; determine region of extended-reality environment to be presented, based on viewpoint and view direction; determine sub-region(s) of region whose rendering information is to be derived from previous rendering information of corresponding sub-region(s) of previously-presented region of extended-reality environment; generate rendering information of sub-region(s) based on previous rendering information; send, to rendering server, information indicating remaining sub-regions required to be re-rendered and pose information indicating viewpoint and view direction; receive, from rendering server, rendering information of remaining sub-regions; merge rendering information of sub-region(s) and rendering information of remaining sub-

Abstract: In a display apparatus, a liquid-crystal structure, arranged in front of an image renderer, is controlled to shift light of a given sub-pixel to target positions according to a shifting sequence in a repeated manner, while output image frames are displayed. To generate a given output image frame, a given target position to which the light is to be shifted is determined based on the shifting sequence. An input colour value of the given sub-pixel provided in a given input image frame is then adjusted to generate an output colour value of the given sub-pixel for the given output image frame, based on an output colour value of at least one other sub-pixel whose light overlaps with the given target position during display of a previous output image frame, and a retention coefficient between a colour of the at least one other sub-pixel and a colour of the given sub-pixel.

Abstract: A display apparatus including pose-tracking means; image renderer per eye; liquid-crystal device including liquid-crystal structure and control circuit; and processor. Processor is configured to: process pose-tracking data to determine user's head pose; detect if rate at which head pose is changing is below predefined threshold rate; if yes, switch on lock mode, select head pose for session of lock mode, and generate output image frames according to head pose during session; if no, generate output image frames according to corresponding head poses of user using pose-tracking data; and display output image frames, whilst shifting light emanating to from pixels of image renderer to multiple positions (P1-P9) in sequential and repeated manner, said shifting causes resolution of output image frames to appear higher than display resolution of image renderer.

Abstract: A display apparatus including gaze-tracking means, image renderers, liquid-crystal devices including liquid-crystal structure and control circuit, to shift light emanating from given pixel of image renderer to multiple positions, given pixel including colour component; and processor configured to: process gaze-tracking data to determine gaze direction of user's eye; determine gaze point; display first output image frame; detect if magnitude of difference between first output value and initial second output value of colour component of given pixel in first and second output image frames exceeds first threshold difference; when detected that magnitude of difference exceeds first threshold difference, update initial second output value to sum of first output value and product of distance factor and difference between initial second output and first output values; and display second output image frame.

Abstract: A method of encoding images and a method of decoding images. The method of encoding comprises dividing an input image into a first input portion and a plurality of input rings that are concentric with the first input portion, the first input portion and the plurality of input rings being shaped as a simple closed curve; storing the first input portion into a first image; packing the plurality of input rings into a second image, second image having a plurality of rows, a given input ring of input image being packed into a corresponding row of second image; and communicating, to a display apparatus, the first image, the second image and information indicative of a size of the first input portion and sizes of the plurality of input rings.