US 11,734,833 B2
Systems and methods for detecting movement of at least one non-line-of-sight object
Alon Refael Heimer, Netanya (IL); Barak Alfassi, Netanya (IL); Ilya Leizerson, Netanya (IL); and Yaron Mayerowicz, Netanya (IL)
Assigned to Elbit Systems C4I and Cyber Ltd., Netanya (IL)
Filed by Elbit Systems C4I and Cyber Ltd., Netanya (IL)
Filed on Feb. 27, 2023, as Appl. No. 18/174,664.
Application 18/174,664 is a continuation of application No. PCT/IL2021/050683, filed on Jun. 8, 2021.
Claims priority of application No. 277062 (IL), filed on Aug. 30, 2020.
Prior Publication US 2023/0215019 A1, Jul. 6, 2023
Int. Cl. G06T 7/20 (2017.01)
CPC G06T 7/20 (2013.01) [G06T 2207/10016 (2013.01); G06T 2207/10048 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A system for detecting movement of at least one non-line-of-sight object, the system comprising:
a camera capable of acquiring images of:
(A) at least part of a first visible object located within a line-of-sight of the camera, being a target, the first visible object being impacted by (i) light that is scattered from the non-line-of-sight object present within a space outside the line-of-sight of the camera and (ii) ambient light, and
(B) at least part of a second visible object located within the line-of-sight of the camera, being a reference, the second visible object being impacted by the ambient light; and
a processing circuitry configured to:
obtain a sequence of at least two successive images acquired by the camera, each of the successive images including a first set of pixels representing the target, and a second set of pixels representing the reference;
analyze at least two images of the sequence for detecting the movement within the space, if any, the at least two images of the sequence being analyzed images, by calculating, for each analyzed image of the analyzed images,
(a) at least one target light intensity value based on at least part of the first set of pixels in the respective analyzed image, thereby giving rise to target light intensity values for the analyzed images,
(b) at least one reference light intensity value based on at least part of the second set of pixels in the respective analyzed image, thereby giving rise to reference light intensity values for the analyzed images, and
(c) at least one compensated light intensity value, being the target light intensity value as modified, based on the reference light intensity value, to reduce an effect, on the target light intensity value, of changes in the ambient light between a first time at which a given image of the sequence is acquired and a second time at which the respective analyzed image is acquired, thereby giving rise to compensated light intensity values for the analyzed images; and
detect the movement within the space upon a variation between the compensated light intensity values across given images of the analyzed images meeting a criterion.