US 11,922,666 B2
Object presence detection using raw images
Keen-Hun Leong, Penang (MY); Kheng Jin Ooi, Penang (MY); and Yueh Mei Kim, Penang (MY)
Assigned to PixArt Imaging Inc., Hsin-Chu (TW)
Filed by PixArt Imaging Inc., Hsin-Chu (TW)
Filed on Apr. 13, 2021, as Appl. No. 17/228,731.
Prior Publication US 2022/0327325 A1, Oct. 13, 2022
Int. Cl. G06V 10/00 (2022.01); G06V 10/145 (2022.01); G06V 10/50 (2022.01); G06V 10/75 (2022.01)
CPC G06V 10/145 (2022.01) [G06V 10/507 (2022.01); G06V 10/751 (2022.01)] 16 Claims
OG exemplary drawing
 
1. A system in a coffee machine for performing object detection to determine presence of a coffee cup for enabling the coffee machine, the system comprising:
a light source; and
an optical image sensor placed directly above an area of the coffee machine where the coffee cup will be placed, the optical image sensor arranged to perform the following steps:
selectively illuminating the area with the light source and capturing a calibration image of the area during a calibration stage, dividing the calibration image into a plurality of quadrants, and calculating a parameter for each of the quadrants, wherein there is no coffee cup in the calibration image;
selectively illuminating the area with the light source and capturing a plurality of raw images of the area during a detection stage, dividing each image of the raw images into a plurality of quadrants, and calculating a parameter for each of the quadrants;
comparing the respective parameters of each quadrant of a raw image with the respective parameters of each quadrant of the calibration image to generate a ratio value for each quadrant; and
comparing the ratio value of each quadrant with a predetermined threshold corresponding to pixel intensity;
wherein when each ratio value of specific quadrants of the quadrants is greater than the predetermined threshold, detection of the coffee cup is confirmed;
wherein the optical image sensor is contained within the coffee machine, the specific quadrants are the central quadrants, and when detection of the coffee cup is confirmed, the coffee machine is enabled to pour coffee.