POINT PATTERN MATCH-BASED CHANGE DETECTION IN A CONSTELLATION OF PREVIOUSLY DETECTED OBJECTS
First Claim
1. A method in a computing device for matching a new constellation of newly detected objects to a previous constellation of previously detected objects, the method comprising:
- for each of a plurality of pairs that includes a previously detected object and a newly detected object,generating a constellation offset based on a distance between the previously detected object and the newly detected object of the pair; and
generating a point pattern matching score indicating a degree to which the new point pattern matches the previous constellation assuming a constellation offset between the new constellation and the previous constellation and factoring in a probabilistic uncertainty model for the locations of the previously detected objects and the newly detected objects;
identifying the point pattern matching score indicating the best match between the new constellation and the previous constellation; and
indicating that the constellation offset resulting in the identified point pattern matching score as a best constellation offset for matching the new constellation with the previous constellation.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and system is provided that applies attribute- and topology-based change detection to objects that were detected on previous scans of a medium. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, detection strength, size, elongation, orientation, etc. The locations define a three-dimensional network topology forming a constellation of previously detected objects. The change detection system stores attributes of the previously detected objects in a constellation database. The change detection system detects changes by comparing the attributes and topological consistency of newly detected objects encountered during a new scan of the medium to previously detected objects in the constellation database. The change detection system may receive the attributes of the newly detected objects as the objects are detected by an object detection system in real time.
-
Citations
32 Claims
-
1. A method in a computing device for matching a new constellation of newly detected objects to a previous constellation of previously detected objects, the method comprising:
-
for each of a plurality of pairs that includes a previously detected object and a newly detected object, generating a constellation offset based on a distance between the previously detected object and the newly detected object of the pair; and generating a point pattern matching score indicating a degree to which the new point pattern matches the previous constellation assuming a constellation offset between the new constellation and the previous constellation and factoring in a probabilistic uncertainty model for the locations of the previously detected objects and the newly detected objects; identifying the point pattern matching score indicating the best match between the new constellation and the previous constellation; and indicating that the constellation offset resulting in the identified point pattern matching score as a best constellation offset for matching the new constellation with the previous constellation. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A computer-readable storage medium storing computer-executable instructions for controlling a computing device to detect a change in newly detected objects from previously detected objects, the computer-executable instructions implementing a method comprising:
for a newly detected object, designating a new constellation to include newly detected objects within a match range of that newly detected object; designating a previous constellation to include previously detected objects with the match range of the newly detected object; matching the new constellation to the previous constellation to identify a best constellation offset; selecting as a matching object the previously detected object that best matches that newly detected object, factoring in a best constellation offset; and generating a change statistic based on a comparison of values of an attribute of the matching object and the newly detected object. - View Dependent Claims (9, 10, 11, 12, 13, 14)
-
15. A computing device for updating a previous constellation of previously detected objects based on a constellation of newly detected objects, comprising:
-
a component that, for each of the newly detected objects, performs a first point pattern match between newly detected objects within a match range of that newly detected object and previously detected objects within a match range of that newly detected object, the first point pattern match being performed using a nominal range of admissible offsets to exclude pairs that include a newly detected object and a previously detected object as a basis for a point pattern match, each point pattern match generating a best constellation offset; a component that refines the range of admissible offsets based on the offsets for the best constellation matches; and a component that, for each of the newly detected objects, performs a second point pattern match between newly detected objects within a match range of the newly detected object and previously detected objects within a match range of the newly detected object, the point pattern match being performed using the refined range of admissible offsets to exclude pairs of a newly detected object and a previously detected object as a basis for a point pattern match; and a component that updates the previous constellation based on the second point pattern matches. - View Dependent Claims (16, 17, 18, 19, 20, 21)
-
-
22. A computer-readable storage medium storing computer-executable instructions for controlling a computing device to match a new constellation of newly detected objects to a previous constellation of previously detected objects, the computer executable instructions comprising:
-
instructions that, for each of a plurality of pairs that includes a previously detected object and a newly detected object, generate a constellation offset based on a distance between the previously detected object and the newly detected object of the pair; and generate point pattern matching score indicating a degree to which the new point pattern matches the previous constellation assuming a constellation offset between the new constellation and the previous constellation and factoring in strength of detection of the previously detected objects; instructions that identify the point pattern matching score indicating the best match between the new constellation and the previous constellation; and instructions that indicate that the constellation offset resulting in the identified point pattern matching score as a best constellation offset for matching the new constellation with the previous constellation. - View Dependent Claims (23, 24, 25, 26, 27, 28)
-
-
29. A computer-readable storage medium storing computer-executable instructions for controlling a computing device to match a new constellation of newly detected objects to a previous constellation of previously detected objects, the computer executable instructions comprising:
-
instructions that, for each of a plurality of pairs that includes a previously detected object and a newly detected object for which the distance between the previously detected object and the newly detected object of the pair lies within the range of admissible offsets, generate a constellation offset based on the distance; and generate a point pattern matching score indicating the degree to which the new point pattern matches the previous constellation assuming a constellation offset between the new constellation and the previous constellation and factoring in strength of detection for the previously detected objects; instructions that identify the point pattern matching score indicating the best match between the new constellation and the previous constellation; and instructions that indicate that the constellation offset resulting in the identified point pattern matching score as a best constellation offset for matching the new constellation with the previous constellation. - View Dependent Claims (30, 31, 32)
-
Specification