Flash detection

• US 10,410,082 B2
• Filed: 07/07/2017
• Issued: 09/10/2019
• Est. Priority Date: 02/24/2014
• Status: Active Grant

• Current Assignee: ELTA Systems Limited (Government of Israel)
• Original Assignee: ELTA Systems Limited (Government of Israel)
• Inventors: Aphek, Ori
• Primary Examiner(s): Mistry, Oneal R
• Application Number:
  US15/644,127
• Publication Number:
  US 20170364767A1
• Time in Patent Office: 795 Days
• CPC Class Codes: G06T 1/60 Memory management
• CPC Class Codes: G06V 10/143 Sensing or illuminating at different wavelengths
• CPC Class Codes: G06V 20/44 Event detection
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: G06V 30/422 Technical drawings; Geographical maps
• CPC Class Codes: H04N 7/12 Systems in which the television signal is transmitted via one channel or a plurality of parallel channels, the bandwidth of each channel being less than the bandwidth of the television signal H04N7/24 takes precedence

Abstract

The present disclosure provides a method including memorizing a sequence of high-resolution images of a scene in a buffer, obtaining radiation emission readings from one or more photo detectors, detecting a suspected flash event based on processing the radiation emission readings from the one or more photo detectors. The method may further include that the detecting occurs at a first instant, retrieving from the buffer high-resolution images of the scene including at least one image that was captured prior to said first instant, and processing the high-resolution images of the scene to determine a geolocation of the suspected flash event.

Claims

1. A method comprising:

obtaining, from a detection system including at least one imaging unit and one or more photo detectors, a sequence of high-resolution images of a scene captured by said at least one imaging unit of the detection system, and radiation emission readings measured from the scene, by said one or more photo detectors of the detection system;

processing the radiation emission readings obtained from the one or more photo detectors to detect a suspected flash event;

processing the high-resolution images to determine a location of the suspected flash event; and

processing said high-resolution images to determine whether the suspected flash event occurred or not, wherein the determining of whether the suspected flash event occurred or not comprises applying motion processing to the high-resolution images to identify a moving object in the scene; and

determining whether the suspected flash event is associated with glint from said moving object, by processing the high-resolution images to determine whether said location of the suspected flash is associated with said moving object;

thereby enabling to validate or disqualify occurrence of the suspected flash event.

2. The method of claim 1, wherein the determining of whether the suspected flash event occurred comprises determining whether the suspected flash event is associated with the glint from said moving object while said moving object is moving in the scene behind a chopping object.

3. The method of claim 2, further comprising disqualifying occurrence of the suspected flash event upon determining that the suspected flash event is associated with said glint from the movement of said moving object behind the chopping object.

4. The method of claim 2, wherein the chopping object is at least one of a grove of trees and a fence.

5. The method of claim 1, wherein the determining of the location of the suspected flash event comprises retrieving, from the sequence of high-resolution images, at least one image without the suspected flash event and at least one image with the suspected flash event, and subtracting the at least one image without the suspected flash event from the at least one image with the suspected flash event to locate the suspected flash event within the images.

6. The method of claim 5, wherein said subtracting is performed by utilizing a block-by-block motion correction to thereby accurately remove background from the image with the suspected flash event.

7. The method according to claim 5, wherein said retrieving comprises determining said at least one image without the suspected flash event and said at least one image with the suspected flash event, by cross-correlating samples of the radiation emission readings from the one or more photo detectors and timings of said high resolution images.

8. The method according to claim 1, further comprising continuously operating a high-resolution camera to capture the high-resolution images of the scene independently from the photodetectors, and regardless of detection of the suspected flash event.

9. A method comprising:

obtaining from a detection system including at least one imaging unit and one or more photo detectors, a sequence of high-resolution images of a scene captured by said at least one imaging unit of the detection system, and radiation emission readings measured from the scene, by said one or more photo detectors of the detection system;

processing the radiation emission readings from the one or more photo detectors to detect a suspected flash event; and

processing the high-resolution images captured by the at least one imaging unit, to determine a location of the suspected flash event, wherein the determining of the location of the suspected flash event comprises;

retrieving, from the sequence of high-resolution images, at least one image without the suspected flash event and at least one image with the suspected flash event, the retrieving comprising determining said at least one image without the suspected flash event and said at least one image with the suspected flash event, by cross-correlating samples of the radiation emission readings from the one or more photo detectors and timings of said high resolution images;

subtracting the at least one image without the suspected flash event from the at least one image with the suspected flash event to locate the suspected flash event within the image; and

processing the high-resolution images to determine whether the suspected flash event occurred or not, by applying motion processing to the high-resolution images to identify a moving object in the scene and determining whether the suspected flash event is associated with glint from said moving object.

10. The method according to claim 9, wherein said subtracting is performed by utilizing a block-by-block motion correction to remove background from the image with the suspected flash event.

11. A system comprising:

a detection system including;

at least one imaging unit capable of capturing a sequence of high-resolution images of a scene sequence, and one or more photo detectors capable of obtaining radiation emission readings from the scene;

a frame buffer connectable to the at least one imaging unit of the detection system and capable of memorizing the sequence of high-resolution images of the scene, which are captured by said at least one imaging unit;

a controller connectable to the one or more photodetectors of the detection system, which provide radiation emission readings from the scene, and configured and operable for detecting a suspected flash event based on processing the radiation emission readings from the one or more photo detectors; and

wherein the controller is configured for determining whether the suspected flash event occurred or not, by processing the high-resolution images captured by said at least one imaging unit, whereby said processing of the high-resolution images comprises;

applying motion processing to the high-resolution images of the scene to identify a moving object in the scene;

processing the high-resolution images to determine a location of the suspected flash event; and

determining whether the suspected flash event is associated with glint from said moving object by determining whether said location of the suspected flash is associated with said moving object;

thereby enabling to validate or disqualify occurrence of the suspected flash event.

12. The system of claim 11, wherein in determining whether the suspected flash event occurred or not, the controller further determines whether the suspected flash event is associated with said glint from the moving object while the moving object is moving in the scene behind a chopping object.

13. The system of claim 12, wherein the controller is adapted to disqualify occurrence of the suspected flash event, upon determining that the glint associated with the movement of the moving object is behind said chopping object.

14. The system of claim 11, wherein the controller is adapted for carrying out the following for determining said location of the suspected flash event:

retrieving, from the sequence of high-resolution images, at least one image without the suspected flash event and at least one image with the suspected flash event; and

subtracting the at least one image without the suspected flash event from the at least one image with the suspected flash event to locate the suspected flash event within the images.

15. The system of claim 14, wherein the controller is configured for carrying out said subtracting by utilizing a block-by-block motion correction to thereby accurately remove background from the image with the suspected flash event.

16. The system of claim 14, wherein said retrieving comprises cross-correlating samples of the radiation emission readings from the one or more photo detectors and timings of said high resolution images to determine said at least one image without the suspected flash event, and said at least one image with the suspected flash event.

17. The system according to claim 11, wherein the controller is connectable to a high-resolution camera that operates continuously to capture the high-resolution images of the scene independently from the photodetectors and regardless of detection of the suspected flash event.

18. A system connectable to a detection system including at least one imaging unit, and one or more photo detectors, for detecting flash events;

the system comprising;

a frame buffer connectable to the at least one imaging unit of the detection system and capable of memorizing a sequence of high-resolution images of a scene captured by said at least one imaging unit;

a controller connectable to the one or more photodetectors of the detection system for obtaining, from said one or more photodetectors, radiation emission readings from the scene;

said controller is configured and operable for detecting a suspected flash event based on processing the radiation emission readings from the one or more photo detectors, and determining whether the suspected flash event occurred or not, by carrying out the following processing on the radiation emission readings from said one or more photo detectors and said high-resolution images captured by said at least one imaging unit;

applying motion processing to the high-resolution images of the scene to identify a moving object in the scene;

processing the high-resolution images to determine a location of the suspected flash event by;

(i) cross-correlating samples of the radiation emission readings from the one or more photo detectors and timings of the high resolution images of said sequence to determine at least one image without the suspected flash event, and at least one image with the suspected flash event;

(ii) retrieving said at least one image without the suspected flash event and said at least one image with the suspected flash event from said sequence of high resolution images; and

(iii) subtracting the at least one image without the suspected flash event from the at least one image with the suspected flash event to locate the suspected flash event within the images; and

thereby determining whether the suspected flash event is associated with glint from said moving object.