US 12,217,441 B2
Item location detection using homographies
Sumedh Vilas Datar, Grapevine, TX (US); Sailesh Bharathwaaj Krishnamurthy, Irving, TX (US); Crystal Maung, Dallas, 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 Nov. 19, 2021, as Appl. No. 17/455,903.
Application 17/455,903 is a continuation in part of application No. 17/362,261, filed on Jun. 29, 2021, granted, now 11,887,332.
Prior Publication US 2022/0414899 A1, Dec. 29, 2022
Int. Cl. G06T 7/292 (2017.01); G06N 20/00 (2019.01); G06T 7/73 (2017.01); G06V 20/64 (2022.01)
CPC G06T 7/292 (2017.01) [G06N 20/00 (2019.01); G06T 7/75 (2017.01); G06V 20/64 (2022.01)] 20 Claims
OG exemplary drawing
 
1. An item tracking system, comprising:
a first camera configured to capture a first image of a global plane for at least a first portion of a platform, wherein:
the global plane represents (x,y) coordinates for the at least a portion of the platform;
the first image comprises a plurality of pixels; and
each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column;
a second camera configured to capture a second image of at least a second portion of the platform, wherein the second portion of the platform at least partially overlaps with the first portion of the platform; and
a memory operable to store:
a first homography associated with the first camera, wherein the first homography is configured to translate between pixel locations in the first image and (x,y) coordinates in the global plane;
a second homography associated with the second camera, wherein the second homography is configured to translate between pixel locations in the second image and (x,y) coordinates in the global plane; and
a processor operably coupled to the first camera, the second camera, and the memory, and configured to:
capture the first image of an item using the first camera;
identify a first plurality of pixels corresponding with the item in the first image;
identify a first pixel location within the first plurality of pixels corresponding with the item in the first image;
apply the first homography to the first pixel location to determine a first (x,y) coordinate identifying a first x-value and a first y-value in the global plane where the item is located;
capture the second image of the item using the second camera;
identify a second plurality of pixels corresponding with the item in the second image;
identify a second pixel location within the second plurality of pixels corresponding with the item in the second image;
apply the second homography to the second pixel location to determine a second (x,y) coordinate identifying a second x-value and a second y-value in the global plane where the item is located;
determine a distance between the first (x,y) coordinate and the second (x,y) coordinate;
compare the distance between the first (x,y) coordinate and the second (x,y) coordinate to a distance threshold value, wherein the distance threshold value identifies a maximum distance between (x,y) coordinates to a member of a cluster for the item;
determine that the distance between the first (x,y) coordinate and the second (x,y) coordinate is less than or equal to the distance threshold value;
associate the first plurality of pixels corresponding with the item in the first image and the second plurality of pixels corresponding with the item in the second image with the cluster for the item; and
output the first plurality of pixels corresponding with the item in the first image and the second plurality of pixels corresponding with the item in the second image.