Patent ID: 11935297
Assignee: OBJECTVIDEO LABS, LLC
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A computer-implemented method comprising:
generating an input video stream comprising at least one image frame that coincides with detection of activity within a threshold distance of a property;
generating timing information for the input video stream, the timing information comprising a respective time stamp for each image frame of the input video stream;
using the input video stream and the timing information, obtaining image frames comprising a pre-event image frame that precedes detection of the activity and a post-event image frame that coincides with detection of the activity;
computing a difference in pixel values by subtracting a first pixel value corresponding to pixels in the pre-event image frame from a second pixel value corresponding to pixels in the post-event image frame;
in response to computing the difference in pixel values, generating a foreground region of the post-event image based on background image modeling applied to the pre-event image;
extracting, using local feature extraction, a set of features from the foreground region;
computing an image score with respect to placement of a candidate item at the property based on the difference in pixel values and the set of features extracted from the foreground region; and
in response to determining that the image score exceeds a threshold score, determining that a first item was delivered to the property or that a second item was removed after being delivered to the property.