Distinguishing between fire and non-fire conditions using cameras

• US 20030214583A1
• Filed: 05/20/2002
• Published: 11/20/2003
• Est. Priority Date: 05/20/2002
• Status: Active Grant

• Current Assignee: Simmonds Precision Products, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Simmonds Precision Products, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Sadok, Mokhtar
• Granted Patent: US 7,245,315 B2
• Time in Patent Office: Days
• US Class Current: 348/143
• CPC Class Codes: G08B 17/125 by using a video camera to detect fire or smoke

Abstract

Detecting fire and non-fire conditions includes receiving a plurality of frames of video information, determining an energy indicator for each of a subset of the plurality of frames, detecting a fire condition in response to the energy indicator for each of the subset of the plurality of frames forming a pattern as a function of time corresponding to a fire condition, and detecting a non-fire condition in response to the energy indicator for each of the subset of the plurality of frames forming a pattern as a function of time corresponding to a non-fire condition. Detecting fire and non-fire conditions may also include comparing energy indicators for each of the subset of the plurality of frames to a reference frame. The reference frame may correspond to a video frame taken when no fire is present, a video frame immediately preceding each of the subset of the plurality of frames, or a video frame immediately preceding a frame that is immediately preceding each of the subset of the plurality of frames.

Claims

1. A method of detecting fire and non-fire conditions, comprising:

receiving a plurality of frames of video information;

determining an energy indicator for each of a subset of the plurality of frames;

detecting a fire condition in response to the energy indicator for each of the subset of the plurality of frames forming a pattern as a function of time corresponding to a fire condition; and

detecting a non-fire condition in response to the energy indicator for each of the subset of the plurality of frames forming a pattern as a function of time corresponding to a non-fire condition.

2. A method, according to claim 1, further comprising:

comparing energy indicators for each of the subset of the plurality of frames to a reference frame.

3. A method, according to claim 2, wherein the reference frame corresponds to a video frame taken when no fire is present.

4. A method, according to claim 2, wherein the reference frame corresponds to a video frame immediately preceding each of the subset of the plurality of frames.

5. A method, according to claim 2, wherein the reference frame corresponds to a video frame immediately preceding a frame that is immediately preceding each of the subset of the plurality of frames.

6. A method, according to claim 1, wherein at least some of the subset of the plurality of frames are provided by a camera having a sensitivity of between 400 nm and 1000 nm.

7. A method, according to claim 6, wherein at least some of the subset of the plurality of frames are provided by a camera that generates 640×

480 pixels per frame.

8. A method, according to claim 7, wherein at least some of the subset of the plurality of frames are provided by a CCD camera.

9. A method, according to claim 7, wherein at least some of the subset of the plurality of frames are provided by a CMOS camera.

10. A method, according to claim 1, wherein at least some of the subset of the plurality of frames are provided by a camera having a sensitivity of between 7 and 14 micrometers.

11. A method, according to claim 10, wherein at least some of the subset of the plurality of frames are provided by an IR camera.

12. A method of detecting fire and non-fire conditions, comprising:

receiving a plurality of frames of video information;

determining edge energy for each of a subset of the plurality of frames;

detecting a fire condition by comparing the edge energy to reference edge energy corresponding to a non-fire condition; and

detecting a non-fire condition by comparing the edge energy to the reference edge energy corresponding to a non-fire condition.

13. A method, according to claim 12, wherein the reference edge energy corresponds to a video frame taken in the presence of fog.

14. A method, according to claim 12, wherein at least some of the subset of the plurality of frames are provided by a camera having a sensitivity of between 400 nm and 1000 nm.

15. A method, according to claim 14, wherein at least some of the subset of the plurality of frames are provided by a camera that generates 640×

480 pixels per frame.

16. A method, according to claim 15, wherein at least some of the subset of the plurality of frames are provided by a CCD camera.

17. A method, according to claim 15, wherein at least some of the subset of the plurality of frames are provided by a CMOS camera.

18. A method, according to claim 12, wherein at least some of the subset of the plurality of frames are provided by a camera having a sensitivity of between 7 and 14 micrometers.

19. A method, according to claim 18, wherein at least some of the subset of the plurality of frames are provided by an IR camera.