Patent ID: 11893759
Assignee: 7-ELEVEN, INC.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. An object tracking system, comprising:
a first sensor configured to capture frames of a global plane for at least a first portion of a space, wherein:
the global plane represents (x,y) coordinates for the at least a portion of the space; and
each frame comprises a plurality of pixels;

a second sensor configured to capture frames of the global plane for at least a second portion of the space; and
a tracking system operably coupled to the first sensor and the second sensor, comprising:
one or more memories operable to store:
a disparity mapping between the first sensor and the second sensor, wherein the disparity mapping maps pixel locations from the first sensor to pixel locations from the second sensor;
a first homography associated with the first sensor, wherein the first homography comprises coefficients that translate between pixel locations in a frame from the first sensor and (x,y) coordinates in the global plane; and
a second homography associated with the second sensor, wherein the second homography comprises coefficients that translate between pixel locations in a frame from the second sensor and (x,y) coordinates in the global plane; and

one or more processors operably coupled to the one or more memories, configured to:
receive a first frame from the first sensor;
identify a first pixel location for a marker within the first frame;
determine an (x,y) coordinate for the marker in the global plane by applying the first homography to the first pixel location;
identify a second pixel location for the marker by applying the second homography to the (x,y) coordinate;
identify a third pixel location by applying the disparity mapping to the first pixel location;
determine a distance difference between the second pixel location and the third pixel location;
compare the distance difference to a difference threshold level; and
recompute at least one of the first homography and the second homography in response to determining that the distance difference exceeds the difference threshold level.