Item location detection using homographies

An item tracking method, comprising:

• capturing a first image of an item using a first camera that is configured to capture the 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;
• identifying a first plurality of pixels corresponding with the item in the first image;
• identifying a first pixel location within the first plurality of pixels corresponding with the item in the first image;
• applying a 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, wherein:
• the first homography is associated with the first camera;
• and
• the first homography is configured to translate between pixel locations in the first image and (x,y) coordinates in the global plane;
• capturing a second image of the item using a second camera that is configured to capture the 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;
• identifying a second plurality of pixels corresponding with the item in the second image;
• identifying a second pixel location within the second plurality of pixels corresponding with the item in the second image;
• applying a 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, wherein:
• the second homography associated with the second camera;
• and
• the second homography is configured to translate between pixel locations in the second image and (x,y) coordinates in the global plane;
• determining a distance between the first (x,y) coordinate and the second (x,y) coordinate;
• comparing 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;
• determining 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;
• associating 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
• outputting 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.

A computer program product comprising executable instructions stored in a non-transitory computer-readable medium that when executed by a processor causes the processor to:

• capture a first image of an item using a first camera that is configured to capture the 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;
• 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 a 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, wherein:
• the first homography is associated with the first camera;
• and
• the first homography is configured to translate between pixel locations in the first image and (x,y) coordinates in the global plane;
• capture a second image of the item using a second camera that is configured to capture the 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;
• 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 a 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, wherein:
• the second homography associated with the second camera;
• and
• the second homography is configured to translate between pixel locations in the second image and (x,y) coordinates in the global plane;
• 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.