PSEUDO-COLOR COVERT NIGHT VISION SECURITY DIGITAL CAMERA SYSTEM

• US 20090079825A1
• Filed: 09/26/2007
• Published: 03/26/2009
• Est. Priority Date: 09/26/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Calnegru, Cristian M.
• Granted Patent: US 8,810,651 B2
• Time in Patent Office: Days
• US Class Current: 348/143
• CPC Class Codes: G08B 13/196 using television cameras
• CPC Class Codes: G08B 15/001 Concealed systems, e.g. disguised alarm systems to make covert systems
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/84 for processing colour signals
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/781 on disks or drums
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 9/8227 the additional signal being at least another television signal

Abstract

A digital security camera system and method for pseudo-color covert night vision is provided. The system includes one or more light sources adapted for providing selective illumination at a plurality of infrared wavelengths, such as 730 nm, 830 nm and 940 nm. A monochrome digital image capture device records multiple images of a target illuminated in the plurality of wavelengths and stored in a storage device. A processor retrieves the set of recorded images and assigns each wavelength to a specific color channel. The color channels are combined into a composite color image.

Claims

1. A digital security camera apparatus comprising:

a light source for generating light at a plurality of discrete wavelength bands for illuminating a target;

a monochrome digital camera;

a switching circuit for activating said light source for generating each of said plurality of discrete wavelength bands sequentially and controlling said monochrome digital camera to sequentially capture images of said target illuminated by each of said plurality of discrete wavelength bands;

a storage device for storing said captured images;

a processor for retrieving said captured images from said storage device, individually assigning each of said plurality of discrete wavelength bands to one of a plurality of color channels, and combining said plurality of color channels to form a pseudo-color composite image.

2. The system as in claim 1, wherein said plurality of discrete wavelength bands are infrared wavelengths.

3. The system as in claim 2, wherein said plurality of discrete wavelength bands have central wavelengths of 730 nm, 830 nm and 940 nm.

4. The system as in claim 1, wherein said captured image illuminated by a first wavelength band of said plurality of discrete wavelength bands is assigned to a Blue color channel, illuminated by a second wavelength band of said plurality of discrete wavelength bands is assigned to a Green color channel and illuminated by a third wavelength band of said plurality of discrete wavelength bands is assigned to a Red color channel, said color channels being combined to form an pseudo-color RGB composite image.

5. A method for providing a pseudo-color composite image, said method comprising:

generating light at a plurality of discrete wavelength bands for illuminating a target;

activating said light source for generating each of said plurality of discrete wavelength bands sequentially;

capturing monochrome images of said target illuminated by each of said plurality of discrete wavelength bands;

storing said captured images in a storage device;

processing said captured images stored in said storage device

retrieving said captured images from said storage device;

assigning each of said plurality of discrete wavelength bands to one of a plurality of color channels; and

combining said plurality of color channels to form a composite image having pseudo-color.

6. The method as in claim 5, wherein said plurality of discrete wavelength bands are infrared wavelength bands.

7. The method as in claim 5, wherein said plurality of discrete wavelength bands have central wavelengths of 730 nm, 830 nm and 940 nm.

8. The method as in claim 5, wherein said captured image illuminated by a first wavelength band of said plurality of discrete wavelength bands is assigned to a Blue color channel, illuminated by a second wavelength band of said plurality of discrete wavelength bands is assigned to a Green color channel and illuminated by a third wavelength band of said plurality of discrete wavelength bands is assigned to a Red color channel, said color channels being combined to form an pseudo-color ROB composite image.

9. A digital security camera apparatus comprising:

a first light source for generating light at a first discrete wavelength band for illuminating a target;

a second light source for generating light at a second discrete wavelength band for illuminating said target;

a third light source for generating light at a third discrete wavelength band for illuminating said target;

a monochrome digital image capture device;

a switching circuit for singly activating said first light source, said second light source and said third light source, and controlling said monochrome digital image capture device to sequentially capture images of said target illuminated by each of said plurality of discrete wavelength bands;

a storage device for storing said captured images; and

a processor for retrieving said captured images from said storage device, individually assigning each of said discrete wavelength bands to one of a plurality of color channels, and combining said plurality of color channels to form a pseudo-color composite image.

10. The system as in claim 9, wherein said first discrete wavelength band, said second discrete wavelength band and said third discrete wavelength band are infrared wavelength bands.

11. The system as in claim 10, wherein said first discrete wavelength band has a central wavelength of 730 nm, said second discrete wavelength band has a central wavelength of 830 nm and said third discrete wavelength band has a central wavelength of 940 nm.

12. The system as in claim 9, wherein said image captured under said first discrete wavelength band is assigned to a Blue color channel, under said second discrete wavelength band is assigned to a Green color channel and under said third discrete wavelength band is assigned to a Red color channel, said color channels being combined to form an pseudo-color RGB composite image.

13. A method for providing a pseudo-color composite image, said method comprising:

generating a first light at a first discrete wavelength band for illuminating a target;

generating a second light at a second discrete wavelength band for illuminating said target;

generating a third light at a third discrete wavelength band for illuminating said target;

capturing, sequentially, images of said target illuminated by each of said first discrete wavelength band, said second discrete wavelength band and said third discrete wavelength band;

storing said captured images;

retrieving said captured images from said storage device;

individually assigning each of said discrete wavelength bands to one of a plurality of color channels; and

combining said plurality of color channels to form a pseudo-color composite image.

14. The system as in claim 13, wherein said first discrete wavelength band, said second discrete wavelength band and said third discrete wavelength band are infrared wavelength bands.

15. The system as in claim 14, wherein said first discrete wavelength band has a central wavelength of 730 nm, said second discrete wavelength band has a central wavelength of 830 nm and said third discrete wavelength band has a central wavelength of 940 nm.

16. The system as in claim 13, wherein said image captured under said first discrete wavelength band is assigned to a Blue color channel, under said second discrete wavelength band is assigned to a Green color channel and under said third discrete wavelength band is assigned to a Red color channel, said color channels being combined to form an pseudo-color RGB composite image.