US 11,756,211 B2
Topview object tracking using a sensor array
Sailesh Bharathwaaj Krishnamurthy, Irving, TX (US); and Shahmeer Ali Mirza, Celina, TX (US)
Assigned to 7-ELEVEN, INC., Irving, TX (US)
Filed by 7-ELEVEN, INC., Irving, TX (US)
Filed on Aug. 25, 2021, as Appl. No. 17/411,386.
Application 17/411,386 is a continuation of application No. 16/663,710, filed on Oct. 25, 2019, granted, now 11,188,763.
Prior Publication US 2021/0383131 A1, Dec. 9, 2021
Int. Cl. G06T 7/246 (2017.01); G06T 7/292 (2017.01); G06T 7/223 (2017.01); G06T 7/215 (2017.01); G06V 20/52 (2022.01); G06V 10/25 (2022.01); G06V 10/44 (2022.01); G06V 10/147 (2022.01); G06V 20/64 (2022.01); G06V 10/24 (2022.01)
CPC G06T 7/246 (2017.01) [G06T 7/215 (2017.01); G06T 7/223 (2017.01); G06T 7/292 (2017.01); G06V 10/147 (2022.01); G06V 10/25 (2022.01); G06V 10/457 (2022.01); G06V 20/52 (2022.01); G06V 20/653 (2022.01); G06T 2207/10021 (2013.01); G06T 2207/30232 (2013.01); G06V 10/245 (2022.01)] 20 Claims
OG exemplary drawing
 
1. An object tracking system, comprising:
a first sensor configured to capture a first frame 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;
the first frame comprises a plurality of pixels;
each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column; and
each pixel in the first frame is associated with a pixel value that indicates a distance between the first sensor and a surface in the space;
a second sensor configured to capture a second frame of at least a second portion of the space, wherein the second portion of the space at least partially overlaps with the first portion of the space to define an overlap region; and
a tracking system operably coupled to the first sensor and the second sensor, comprising:
one or more memories operable to store:
a first homography associated with the first sensor, wherein the first homography is configured to:
translate between pixel locations in the first frame and (x,y) coordinates in the global plane; and
translate between pixel values in the first frame and z-coordinates in the global plane;
a first tracking list associated with the first sensor, wherein the first tracking list identifies:
an object identifier for an object being tracked by the first sensor; and
pixel location information corresponding with a location of the object in the first frame; and
a second tracking list associated with the second sensor; and
one or more processors operably coupled to the one or more memories, configured to:
receive the first frame;
identify the object within the first frame;
determine a first pixel location in the first frame for the object, wherein the first pixel location comprises a first pixel row and a first pixel column of the first frame;
determine a first pixel value at the first pixel location;
determine the object is within the overlap region with the second sensor based on the first pixel location;
in response to determining that the object is within the overlap region with the second sensor:
apply the first homography to the first pixel value to determine a first height for the object;
identify the object identifier for the object from the first tracking list;
store the object identifier for the object in the second tracking list; and
store the first height for the object in the second tracking list, wherein the second tracking list is separate from the first tracking list.