Surveillance system method and apparatus

• US 6,462,774 B1
• Filed: 12/20/1999
• Issued: 10/08/2002
• Est. Priority Date: 12/20/1999
• Status: Expired due to Fees

• Current Assignee: Dale Bildstein
• Original Assignee: Dale Bildstein
• Inventors: Bildstein, Dale
• Primary Examiner(s): Kelley, Chris
• Assistant Examiner(s): SENFI, BEHROOZ M
• Application Number:
  US09/466,032
• Time in Patent Office: 1,023 Days
• Field of Search: 348/143, 348/161, 348/220, 348/159, 348/155, 348/798, 382/274, 382/254, 382/271, 382/162, 382/167, 382/141
• US Class Current: 348/143
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A surveillance system that monitors video signals (composite or s-video) from surveillance cameras to detect a degradation of the ambient lighting sources in and around public and private areas. The system also monitors for the black level of a video signal from a surveillance camera that is created by situations such as the covering of an operating camera or spray paint put on camera lenses by vandals. The system also monitors for loss of video that may be caused by loss of power, vandals damaging cameras, or cutting video cables. The surveillance system as a whole can be used with existing video equipment to monitor and detect programmed levels of the previous described situations and to supply alarm signals to an existing alarm station or to a remote alarm station.

Claims

1. A computerized light monitoring system for use in combination with a video surveillance system that includes a surveillance camera producing video signals corresponding to light levels within a defined field of view, said monitoring system comprising:

a video signal input pathway for receiving video signals from the surveillance camera;

a digitizer combined with the signal input pathway for translating video signals into digital light level data;

a digitizer controller combined with the digitizer for selecting light level data corresponding to predetermined sample points within the field of view;

a first memory combined with the digitizer and digitizer controller for storing selected light level data;

a second memory combined with the processing unit for storing normal operation settings programmed into the monitoring system;

a loss of video signal detector combined with the video signal input pathway and digitizer controller for detecting a loss of video signals from the video camera;

a processing unit having a data input pathway and a data output pathway combined with the digitizer, digitizer controller, and first and second memories, said processing unit detecting degradation of light levels within a field of view, detecting black level conditions, and detecting a loss of video signal from the system and producing an output signal over the data output pathway corresponding to the condition detected;

an alarm signal generator combined with the processing unit and being capable of generating at least one alarm signal; and

timing circuitry combined with the processing unit for monitoring a durational requirement associated with an alarm condition.

2. The light monitoring device of claim 1 further comprising:

a multiplexor combined with the video signal input pathway.

3. The light monitoring device of claim 1 further comprising:

real time clock circuitry combined with the processing unit to enable recording of time corresponding to occurrence of alarm condition events.

4. The light monitoring device of claim 1 wherein the processing unit data input pathway comprises a keyboard.

5. The light monitoring device of claim 1 wherein the processing unit data input and output pathways comprise a serial port.

6. The light monitoring device of claim 1 wherein the second memory is a non-volatile memory and is for storing data comprising user input reference light levels, light level degradation tolerance levels, black level sensitivity, and valid alarm condition requirements for light level degradation alarms, loss of video signal alarms, and black level alarms.

7. The light monitoring device of claim 1 further comprising:

a video signal output pathway combined with the processing unit, digitizer, and first and second memories, and in which the video signal output is a standard composite video signal for composite monitors.

8. The light monitoring device of claim 1 wherein the predetermined sample points comprise a matrix of 12 by 15 points contained in the monitored field of view.

9. A method for use in combination with a video surveillance system that includes a surveillance camera producing video signals corresponding to light levels within a defined field of view for detecting degradation of light levels within the field of view, detecting interference with the surveillance system, and detecting and reporting a loss of video signal from the system, said method comprising the steps of:

creating reference light levels at selected sample points within the field of view;

receiving a video signal containing luminance data relating to one or more of the selected sample points within the field of view;

monitoring and storing the luminance data;

performing light degradation alarm condition verification steps if the luminance data indicates that light levels for the selected sample points are less than the reference light levels corresponding to these points by an amount greater than a predetermined light level degradation tolerance;

generating a light degradation alarm signal if the light degradation alarm condition verification steps demonstrate that a valid light degradation alarm condition exists;

performing black level alarm condition verification steps if the luminance data indicates that light levels for the selected sample points are less than the reference light levels corresponding to these points by an amount greater than a predetermined black level sensitivity tolerance;

generating a black level alarm signal if the black level alarm condition verification steps demonstrate that a valid black level alarm condition exists;

monitoring the video signal to detect a loss of synchronization or luminance corresponding to a loss of video signal;

performing loss of video signal alarm condition verification steps if the loss of video signal is detected; and

generating a loss of video signal alarm signal if the loss of video signal alarm condition verification steps demonstrate that a valid loss of video signal alarm condition exists.

10. The method of claim 9 wherein the light level degradation verification steps comprise the steps of:

testing for a predetermined period of time the light level data corresponding to the point or combination of points that have indicated a light level degradation; and

verifying existence of a valid light level degradation alarm condition if the light level degradation has been maintained throughout the predetermined period of time.

11. The method of claim 9 wherein the light level degradation verification steps comprise the steps of:

performing an initial test for a first predetermined period of time to determine if the light level data corresponding to the point or combination of points that have indicated a light level degradation continue to indicate the presence of a light level degradation;

performing a predetermined number of follow up tests to determine if the light level data corresponding to the point or combination of points that have indicated a light level degradation continue to indicate the presence of a light level degradation throughout periods of time comprising the first predetermined period of time and following at least one light level degradation verification delay period comprising a second predetermined period of time; and

verifying the existence of a valid light level degradation alarm condition if the light level degradation is detected throughout the initial verification test and the predetermined number of follow up verification tests.

12. The method of claim 9 wherein the black level degradation verification steps comprise the steps of:

testing for a predetermined period of time the light level data corresponding to the point or combination of points that have indicated a black level; and

verifying the existence of a valid black level alarm condition if the black level has been maintained throughout the predetermined period of time.

13. The method of claim 9 wherein the black level degradation verification steps comprise the steps of:

performing an initial test for a first predetermined period of time to determine if the light level data corresponding to the point or combination of points that have indicated a black level continue to indicate the presence of a black level;

performing a predetermined number of follow up tests to determine if the light level data corresponding to the point or combination of points that have indicated a black level continue to indicate the presence of a black level throughout periods of time comprising the first predetermined period of time and following at least one black level verification delay period comprising a second predetermined period of time;

verifying the existence of a valid black level alarm condition if the black level is detected throughout the initial verification test and the predetermined number of follow up verification tests.

14. The method of claim 9 wherein the loss of video verification steps comprise:

testing the luminance portion of the signal for a predetermined period of time to detect the loss of video and eliminate false alarms based on fast or intermittent signals.

15. The method of claim 9 further comprising the step of:

logging the time corresponding to the generation of a valid alarm condition signal.

16. The method of claim 9 wherein the generation of black level alarm condition signals is stopped upon determination that the monitored light levels are no longer below black level sensitivity levels.

17. The method of claim 9 wherein a light level degradation alarm condition signal must be terminated manually.