公开(公告)号：US20240095958A1

公开(公告)日：2024-03-21

申请号：US18466379

申请日：2023-09-13

Applicant: Apple Inc.

Inventor： Shuntaro Yamazaki ,  Ravi Teja Sukhavasi ,  Oleg Naroditsky ,  Stergios Roumeliotis ,  Daniel C Byrnes

IPC: G06T7/80 ,  G06T7/00 ,  G06T7/20 ,  G06V10/74 ,  H04N23/695

CPC classification number: G06T7/80 ,  G06T7/0002 ,  G06T7/20 ,  G06V10/761 ,  H04N23/695 ,  G06T2207/30168 ,  G06V2201/07

Abstract: Methods for performing a calibration process for outward-facing cameras on devices such as head-mounted display devices are disclosed. Extrinsic parameters of the camera are first estimated using inputs to the calibration process such as information from an inertial measurement unit and points of interest within images captured by the camera that are tracked with time. Then, extrinsic and intrinsic parameters are concurrently determined in an optimization problem such that updated values of said parameters may be stored and used by applications that run on the device and make use of the camera. The calibration process may be extended to concurrently calibrate multiple cameras based, at least in part, on information from the inertial measurement unit that is local to the camera.

公开(公告)号：US20240104778A1

公开(公告)日：2024-03-28

申请号：US18466426

申请日：2023-09-13

Applicant: Apple Inc.

Inventor： Tianheng Wang ,  Stergios Roumeliotis ,  Shuntaro Yamazaki ,  Oleg Naroditsky

IPC: G06T7/80 ,  G02B27/01 ,  H04N13/246

CPC classification number: G06T7/85 ,  G02B27/0172 ,  H04N13/246 ,  G02B2027/0134

Abstract: Methods for performing a camera calibration process for outward-facing cameras on devices such as head-mounted display devices are disclosed. Using cameras with overlapping fields of view, relative rotational parameters of the cameras with respect to one another may be determined using an optimization technique such as a two-view bundle adjustment algorithm. A statistical analysis of the relative rotational parameters of the cameras, determined for a plurality of moments in time, may then be made to provide updated relative rotational parameters for recalibration of the cameras. A camera calibration process, such as those disclosed, may not depend on tracking points of interest over multiple moments in time, but rather on a convergence of the relative rotational parameters determined for respective moments in time.