APPARATUS AND METHODS FOR USE IN FLASH DETECTION

• US 20070125951A1
• Filed: 11/08/2006
• Published: 06/07/2007
• Est. Priority Date: 11/08/2005
• Status: Active Grant

• Current Assignee: General Atomics, Inc.
• Original Assignee: General Atomics, Inc.
• Inventors: Snider, Robin, McGee, Jeffrey, Perry, Michael
• Granted Patent: US 7,732,769 B2
• Time in Patent Office: Days
• US Class Current: 250/363.30
• CPC Class Codes: F41G 3/147 based on detection of a firing weapon
• 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: G08B 13/19613 Recognition of a predetermined image pattern or behaviour pattern indicating theft or intrusion
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/73 by influencing the exposure time

Abstract

The present embodiments provide methods, systems and apparatuses that detect, classify and locate flash events. In some implementations, some of the methods detect a flash event, trigger an imaging system in response to detecting the flash event to capture an image of an area that includes the flash event, and determines a location of the flash event.

Claims

1. A method of detecting flash events, the method comprising:

detecting a flash event;

triggering an imaging system in response to detecting the flash event to capture a first image including at least a portion of the flash event; and

determining a location of the flash event.

2. The method of claim 1, further comprises:

isolating the captured flash event based at least in part on the first image.

3. The method of claim 1, further comprises:

wherein the determining step comprises determining a location of the flash event within a field of view of the imaging system.

4. The method of claim 3, further comprising:

triggering the imaging system to capture a second image with substantially the same field of view as the first image and without the flash event; and

the isolating the captured flash event comprises subtracting the second image from the first image producing a difference image comprising the captured flash event.

5. The method of claim 1, wherein the triggering of the imaging system comprises determining a temporal signature of the detected flash event, and determining whether the temporal signature correlates with a known temporal signature.

6. The method of claim 5, wherein the triggering comprises generating a spectral signature of the detected flash event, and determining whether the spectral signature correlates with a known spectral signature and implementing the triggering when both the temporal and spectral signatures correlate with the known temporal signature and the known spectral signature.

7. A method of detecting flash events, the method comprising:

detecting a flash event;

temporally evaluating the flash event;

determining whether the flash event is an event of interest based on the temporal evaluation; and

triggering an imaging system to capture a first image including the flash event when the flash event is an event of interest.

8. The method of claim 7, wherein the temporally evaluating the flash event comprises determining whether a rise time of the flash event meets a threshold rise time.

9. The method of claim 7, further comprising:

spectrally evaluating the flash event; and

wherein the determining whether the flash event is an event of interest comprises determining whether the flash event is an event of interest based on the temporal and spectral evaluations.

10. The method of claim 9, further comprises:

classifying the flash event based on the spectral evaluation.

11. The method of claim 7, further comprising:

triggering the imaging system to capture a second image after the flash event;

processing the first image and the second image to isolate the flash event within a field of view of the imaging device.

12. The method of claim 11, further comprises:

subtracting the second image from the first image producing a difference image that isolates the flash event within the field of view of the first image; and

determining a geo-location of the flash event based on the isolated flash event.

13. A method of detecting a flash, comprising:

detecting a flash event;

determining a portion of a temporal signature of the flash event while the flash event is in progress;

evaluating the portion of the temporal signature;

determining whether the flash event is a flash event of interest based on the portion of the temporal signature; and

triggering an imaging system to capture an image including a portion of the flash event when the flash event is determined to be a flash event of interest based at least on the portion of the temporal signature.

14. The method of claim 13, further comprising:

determining a spectral signature of at least a portion of the flash event;

evaluating the spectral signature; and

wherein the determining whether the flash event is the flash event of interest comprises determining whether the portion of the temporal signature and the spectral signature correspond with known signatures of interest.

15. The method of claim 14, wherein the detecting the flash comprises detecting a first wavelength band of the flash and a second wavelength band of the flash;

wherein the determining the spectral signature comprises determining the spectral signature as a function of the detected first wavelength band of the flash and the detected second wavelength band of the flash.

16. The method of claim 13, wherein the evaluating the portion of the temporal signature comprises transforming the temporal signature to a transformed temporal signature;

and

the determining whether the flash event is the flash event of interest comprises comparing the transformed temporal signature with one or more known transformed temporal signatures.

17. A system that detects flash events, the system comprising:

a first detector that detects a flash event and generates a first detector output representative of the detected flash event;

an imaging system; and

a discriminator coupled with the first detector and the imaging system, wherein the discriminator receives the first detector output, determines whether the flash event is a potential flash event of interest and triggers the imaging system to capture a first image including at least a portion of the flash event when the flash event is the potential flash event of interest.

18. The system of claim 17, further comprising:

a second detector coupled with the discriminator;

wherein the first detector detects a first wavelength band of the flash event and generates the first output representative of the first wavelength band of the detected flash event;

the second detector detects the flash event based on a second wavelength band and generates a second detector output representative of the second wavelength band of the detected flash event; and

the discriminator couples with the second detector and determines whether the flash event is the potential flash event of interest based on the first and second detector outputs.

19. The system of claim 18, wherein the discriminator determines a spectral signature based on the detected first and second wavelength bands of the flash event, and determines whether the spectral signature correlates with a known spectral signature.

20. The system of claim 17, wherein the imaging system comprises a first imaging device that captures the first image including the portion of the flash event, and a second image comprising substantially the same field of view of the first image and without the flash event.

21. The system of claim 20, further comprising:

an image subtractor coupled with the imaging system to receive the first and second images and to subtract the first and second images to produce a difference image including the portion of the flash event.

22. The system of claim 21, further comprising:

a location system coupled with the discriminator that identifies a geo-location of the flash event based on the portion of the flash event in the difference image.

23. The system of claim 17, further comprising:

a location system coupled with the discriminator that isolate the flash event within a field of view of the imaging system and identifies a geo-location of the flash event.

24. The system of claim 17, wherein the discriminator determines a rise time of the first detector output and whether the rise time correlates with a known rise time such that the discriminator identifies the detected flash event as a flash of interest and triggers the imaging system.

25. A method of detecting flash events, the method comprising:

detecting a flash event;

spectrally evaluating the flash event;

determining whether the flash event is an event of interest based on the spectral evaluation; and

triggering an imaging system to capture a first image including at least a portion of the flash event when the flash event is an event of interest.

26. The method of claim 25, wherein the detecting the flash event comprises detecting a first wavelength band of at least a portion of the flash event and a second wavelength band of at least a portion of the flash event;

and

wherein the spectrally evaluating the flash event comprises determining a spectral signature of the flash event as a function of the detected first wavelength band of the flash event and the detected second wavelength band of the flash event.

27. A method of detecting a flash, comprising:

detecting a flash;

capturing a first image including a portion of the flash event;

capturing a second image that does not include the flash event; and

processing the first and second images with respect to the flash event.

28. A method of detecting a flash event from weaponry, comprising:

detecting the flash event from the weaponry;

taking a first image including the flash event in response to detecting the flash event.