US 12,353,783 B2
Time synchronization for shared extended reality experiences
Jordy Innocentius Ajanohoun, Vienna (AT); Markus Diem, Vienna (AT); Georgios Evangelidis, Vienna (AT); and Matthew Penney, Vienna (AT)
Assigned to SNAP INC., Santa Monica, CA (US)
Filed by Snap Inc., Santa Monica, CA (US)
Filed on Oct. 5, 2023, as Appl. No. 18/481,804.
Claims priority of application No. 20230100691 (GR), filed on Aug. 24, 2023.
Prior Publication US 2025/0068374 A1, Feb. 27, 2025
Int. Cl. G06F 3/01 (2006.01); G06F 3/14 (2006.01)
CPC G06F 3/1454 (2013.01) [G06F 3/011 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
capturing, by a first extended reality (XR) device, images of a wearer of a second XR device, the first XR device and the second XR device being colocated in an environment, and the images captured at different points in time;
using the images to determine a time offset between a first clock of the first XR device and a second clock of the second XR device by:
processing each of the images to determine time-indexed positions of a visual feature based on the first clock,
generating, based on the time-indexed positions of the visual feature, an estimated trajectory of the second XR device, and
matching, using the time offset, the estimated trajectory of the second XR device with a pose trajectory of the second XR device that is based on the second clock;
synchronizing, based on the time offset, the first clock and the second clock; and
establishing a shared coordinate system to enable alignment of virtual content that is simultaneously presented by the first XR device and the second XR device based on the synchronization of the first clock and the second clock.