12. Alarm Assessment - Sandia National Laboratories12 - Alarm Assessment The Twenty-Sixth International Training Course Page 2 Alarm Assessment INFCIRC 225 Revision 5 Recommendations

12 - Alarm Assessment

The Twenty-Sixth International Training Course

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12. Alarm Assessment

October 24 – November 11, 2016Albuquerque, New Mexico, USA

Gabe Birch

Alarm Assessment

Learn ing Object ives

After completing this module, you should be able to:• Discuss the purpose of alarm assessment• List alarm assessment methods• Identify response force assessment components• Identify video assessment system components &

requirements• Discuss design considerations for video assessment

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Alarm Assessment

INFCIRC 225 Revision 5 Recommendations for Cat I, II, and III Nuclear Material

4.15. Provision should be made for detecting unauthorized intrusion and for appropriate action by sufficient guards and/or response forces to address a nuclear security event.

4.19. Contingency plans should be prepared to counter malicious acts effectively and to provide for appropriate response by guards or response forces. Such plans should also provide for the training of facility personnel in their actions.

4.23. A protected area should be located inside a limited access area. The protected area perimeter should be equipped with a physical barrier, intrusion detection and assessment to detect unauthorized access.

These protection measures should be configured to provide time for assessment of the cause of alarms, and provide adequate delay for an appropriate response, under all operational conditions.

Alarms generated by intrusion detection sensors should be promptly and accurately assessed and appropriate action taken.

4.47. Provisions, including redundancy measures, should be in place to ensure that the functions of the central alarm station in monitoring and assessment of alarms, initiation of response and communication can continue during an emergency (e.g. a backup alarm station). 3

Alarm Assessment

INFCIRC 225 Rev is ion 5 Recommendations for H igh-Consequence Fac i l i t i es

5.21. A protected area should be located inside a limited access area. The protected area perimeter should be equipped with a physical barrier, intrusion detection and assessment to detect unauthorized access. These protection measures should be configured to provide time for assessment of the cause of alarms, and provide adequate delay for an appropriate response, under all operational conditions. Alarms generated by intrusion detection sensors should be promptly and accurately assessed, and appropriate action taken.

5.36. A permanently staffed central alarm station should be provided for monitoring and assessment of alarms, initiation of response, and communication with the guards, response forces, and facility management.Provisions, including redundancy measures, should be in place to ensure that the functions of the central alarm station in monitoring and assessment of alarms, initiation of response and communication can continue during an emergency (e.g. backup alarm station).

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Alarm Assessment

A larm Assessment

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Physical Protection System Elements

Detection

Intrusion Detection

Entry Control

Contraband Detection

Alarm Communications and Display

Passive Delay

Active Delay

Response Force (RF)

RF Training and Tactics

RF Equipment

RF Communications

Delay Response

Alarm Assessment

Alarm assessment: Security operator determines the cause of an alarm

Completes the detection function Provides information if alarm is real or

nuisance/false alarm Provides information for response force action

• How many intruders?• What equipment are intruders bringing in?

Alarm Assessment

What is A larm Assessment?

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Detection is not complete without Assessment

SensorActivatedSensor

ActivatedSensor

Activated

AlarmSignal

Initiated

AlarmSignal

Initiated

AlarmSignal

Initiated

AlarmReported

AlarmReported

AlarmReported

Alarm Assessed

Alarm Assessed

Alarm Assessed



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Alarm Assessment

Assessment Methods

• Personnel

• Technology

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Alarm Assessment

Assessment Methods

• Personnel Assessment by on-site personnel

• Guards or security officers• Local law enforcement (police)

• Technology Assessment camera display at

Central Alarm Station

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Alarm Assessment

Assessment with Personnel

• Assessment with Security Personnel Elevated towers or hardened response team building Dedicated response team Response equipment and vehicles Patrols

Alarm Assessment

Assessment with Personnel

• Advantages Flexible deployment

• Special situations, different target locations

If intrusion, provide immediate response and/or delay Patrols provide detection and deterrent capabilities

• Disadvantages Time between alarm and assessment reduces probability of

correct assessment Can tolerate only a limited number of nuisance alarms Labor costs: expensive

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Alarm Assessment

Modern Video Assessment Systems

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Intrusion Detection

Event

Video Subsystem

Alarm Assessment

Assessment with Video Technology

• Assessment with cameras and video monitors Assessment video displayed on monitors at a Central Alarm

Station (CAS) for operator assessment Complete camera coverage of entire sensored detection areas so

any location where an alarm can be created can be assessed with cameras

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Alarm Assessment

Assessment with Video Technology (cont ’d)

• Advantages Efficient use of personnel

• One person can assess multiple areas• Operator alerted to alarm• Nuisance alarms quickly assessed

Electronics perform consistently Minimal time between alarm and assessment / response Pre-and post-alarm video recording possible

• Disadvantages Initial expense for infrastructure Expense for ongoing testing and maintenance

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Alarm Assessment

V ideo Assessment and Video Survei l lance

Assessment – Video monitor displays the scenes captured by a camera, ONLY when triggered by an alarm from a sensor, to alert an operator of intrusion into sensored area

Surveillance – Scenes are continuously displayed on a video monitor of an area that does NOT have sensors for intrusion detection

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Alarm Assessment

V ideo Survei l lance

• Continually monitor activity in an area without an intrusion sensor to cause an alarm and direct CAS operator attention to a specific event or areas

• Low probability of detection Used when time is not critical to an event

• Can be useful for specific activities, such as observing deliveries or construction work

• Is usually effective for short periods of time and for watching a single area

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Alarm Assessment

Three Major E lements for E f fec t ive V ideo Assessment

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Camera Lens

Lighting



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Alarm Assessment

Env i ronmental – Factors to Consider

Environmental considerations Snow, rain, fog, and other environmental factors should be

considered prior to investing in technology Technology typically performs about the same as personnel for

assessment Fair weather visibility

Adequate illumination in detection zone

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Alarm Assessment

Heavy Snow

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Ra in

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Heavy Rain with Thermal Imager

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Fog

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B l ind Spot

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Day and Night Exter ior Camera View

• Observe camera views for adequate image: daytime and nighttime

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Day Night

Alarm Assessment

Cameras

• Function Converts a scene image to a video image • Types

Black & White Color Day/Night – color during day; B&W at night Near-infrared (IR) enhanced black & white Intensified Thermal Imager

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Cameras of different technologies used together provide a wide spectrum of solutions for specific applications, particularly at low light levels or for an obscure scene

These cameras can be analog or digital



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Examples of Inter ior Cameras

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Alarm Assessment

Examples of Exter ior Cameras

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C lose-ups o f Exter io r Cameras w i th Enc losures (Hous ings)• Many exterior cameras are just interior cameras mounted

in an environmental enclosure

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Alarm Assessment

Some of the Conf igurat ionsof Commerc ia l Pan-T i l t -Zoom Cameras

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Alarm Assessment

Some of the Conf igurat ions o f Commerc ia l D ig i ta l IP Cameras

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• Similar to analog cameras but with Local Area Network (LAN) connection

• Video images are compressed to minimize bandwidth use• Can be externally powered or use “Power over Ethernet”• Have IP address for Ethernet connection• Encoder modules are required for interfacing analog

cameras to the network• Can send changes to the digital IP camera settings from

the Alarm Monitoring Station• Can install video motion detection software

in digital cameras

Alarm Assessment

D ig i ta l IP Cameras

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Alarm Assessment

F ixed and PTZ Cameras

• Fixed Camera Non-motorized mount Fixed focal length lens

• Pan-Tilt Zoom-(PTZ) Camera Motorized mount Motorized zoom lens

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Alarm Assessment

F i xed and PTZ Camera – Factors to Cons ider

• Fixed Camera Always pointed at the area of interest

• Assessment – detection sensor area

Captures pre-alarm and post-alarm video Requires more cameras for complete coverage

• PTZ Camera Low probability camera will be pointed at alarm location Single PTZ camera cannot provide video for two

simultaneous alarms in camera coverage area Requires fewer cameras for complete coverage Requires an operator to “follow” some incidents with PTZ’s joy

stick mechanism

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• Color enhances daylight scenes Color at night – gold-brown images with sodium vapor lamps

• Standard black-and-white camera has 18% more resolution than color

• Day/Night cameras Color during day, switches to black-and-white mode at night

Alarm Assessment

Co lor vs. B lack-and-White Cameras

33Black and White

ColorColor at Night

Alarm Assessment

Day / Night Cameras

Some cameras are color during the day and black-and-white at night Sensor measures ambient light level and controls switching from day

to night mode Can adjust light level when switchover occurs Camera monitors video level and switches when scene is too dark

Mechanically removes infrared cut filter - allows camera in black-and-white mode to see in near infrared spectrum Increases amount of scene illumination reaching camera imager

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Day / Night Cameras (cont ’d)

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Alarm Assessment

Thermal Cameras

• A thermal camera responds to emitted thermal / infrared energy

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Thermal Camera Propert ies

Thermal cameras are a passive device Do not require illumination to produce a usable video image Respond to the differences in temperature of objects against a

background temperature reference Video images are based on the temperatures of objects Thermal cameras are relatively expensive compared to visible light

cameras

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Alarm Assessment

Two Examples of Thermal Camera Images

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Thermal Camera Video

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Radar Track.avi

Alarm Assessment

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Intens i f ied Low- l ight Cameras

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CameraSection

IntensifierSection

Alarm Assessment

Intens i f ied Low- l ight Cameras (cont ’d.)

• Intensified low-light cameras respond to near-infrared illumination from stars, the moon, and artificial lighting

• Intensified cameras are light receivers only do not emit infrared light

• These cameras are more expensive than standard cameras

• The low-light Intensifier has a limited life of approximately 2500 to 3500 hours of use

• Bright light sources in the scene can distort images captured by the intensified low-light camera

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Alarm Assessment

Near-IR Sens i t ive Cameras

• Infrared sensitive cameras operate in black-and-white mode with enhanced sensitivity to the near-infrared portion of the light spectrum

• Requires an infrared light source for scene illumination. An infrared light source can be seen with night vision goggles could detract from their usefulness in some situations

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Near Infrared

Visible



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Near-IR Sensi t ive Camera Image

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Alarm Assessment

V is ib le L ight Camera Imager

• The camera imager is the part of a camera that captures the optical image and converts it to video signals

• Several solid-state imagers are available – attributes include:

Resolution

Sensitivity

Color, black-and-white, or near-IR enhanced

Quality standard resolution cameras are usually• ~640 horizontal pixels resolution for Color

• ~760 horizontal pixels resolution for black-and-white

Megapixel cameras have 1280-4400 pixels horizontal resolution

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Alarm Assessment

Imager Format

Format/Size (Wi)1 inch = 16 mm diagonal = 9.6 mm X12.8 mm

2/3 inch = 11 mm diagonal = 6.6 mm X 8.8 mm1/2 inch = 8 mm diagonal = 4.8 mm X 6.4 mm VARIES1/3 inch = 6 mm diagonal = 3.6 mm X 4.8 mm VARIES1/4 inch = 4 mm diagonal = 2.4 mm X 3.2 mm1/6 inch = 3 mm diagonal = 1.8 mm X 2.4 mm1/8 inch = 2 mm diagonal = 1.2 mm X 1.6 mm

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Format – Diagonal dimension of pixel area imager size specified in English units

English unit designation originally established for CRT-type imaging devices

English to metric conversion –measurement not equivalent size

6mm

4.8mm

3.6mm

1/3-inch Imager

Imager Format

(Wi) = Width of imager

Alarm Assessment

Camera Lens

Focuses reflected light from the scene on the camera imager Determines size of scene image projected onto the camera imager at

a specified distance behind the lens Lens selection factors include:

Format Focal length Field of View (FOV) Aperture Resolution

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Alarm Assessment

Lens Format

Lens Format: Diameter of projected image circle at the distance behind the lens where imager is located

The lens has a format specification like camera imager Lens format must match the camera format size to optimize

video image display on camera sensor

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Lens Format (cont ’d.)

Lens Format 1/8" 1/6" 1/4" 1/3" 1/2" 2/3" 1"

Imager Width (Wi)1.6mm

2.4mm

3.2mm

4.8mm

6.4mm

8.8mm

12.8mm

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The lens has a format specification like camera imager Lens format must match the camera format size to optimize

video image display on camera sensor Standard format sizes are

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Alarm Assessment

Lens Format Mismatch

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Example 1 Mismatch Example 2 Mismatch

Format of the lens must match the format of the camera imager

Below are depictions of matched, smaller format lens, and larger format lens mismatch

Alarm Assessment

Format Mismatch Example 1

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Example 1 Mismatch: Lens format smaller than imager format



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Alarm Assessment

Format Mismatch Example 2Example 2 Mismatch: Lens format larger than imager format• Field of view is smaller than specified for the lens• Portion of field of view is focused outside the imager

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View with Matched Format View with Mismatched Format

Lens Focal Length

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Lens focal length determines field of view and image magnification Wide angle lenses have small focal lengths for near views Telephoto lenses have large focal lengths for distance views

Smaller numbers indicate a shorter distance & wider field of view (e.g., 4mm, 6mm)

Larger numbers indicate longer distance & more narrow field of view (e.g., 50mm, 75mm)

Object Distance

Focal Length

Camera

Short FocalLength Lens

Medium FocalLength Lens

Long FocalLength Lens

Focal Length: Distance from the lens to the camera imager when lens is focused at infinity

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24 mm 50 mm

100 mm 250 mm Cou

rtes

y of

Mic

hig

an T

ech

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Examples o f an Image at Four D i f fe rent Foca l Lengths

Alarm Assessment

Lens Aperture

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Regulates amount of light that passes onto the imager Can be manual or electronic adjustment Calibrated in f-numbers or f-stops

Manual Iris – For use where the amount of light is constantAutomatic Iris – For use where the amount of light is not constant –

Controlled by signal from camera

Alarm Assessment

Aperture: Adjustable opening that controls the amount of light entering the lens



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Levels of Assessment Resolut ion

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Detection

DeterminePresence ofObject

Identification

DetermineIdentity ofObject

DetermineNuisance or Real Alarms

Classification

Important factors are Contrast, Motion, and Upright Human Figure

2‐3 pixels/30 cm 6‐9 pixels/30 cm 10‐16 pixels/30cm

Alarm Assessment

Assessment Resolut ion Detect ion

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Assessment Resolut ion Class i f icat ion

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Alarm Assessment

Assessment Resolut ion Ident i f icat ion

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• Camera resolution is commonly measured using a standardized resolution chart

A laboratory chart, field chart, and Rotakinfield resolution chart are shown

Resolution limitation is location where distinct black and white lines are no longer distinguishable

Camera Resolut ion Measurements

Alarm Assessment

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Alarm Assessment

Assessment Resolut ion (cont ’d.)

• Dependent on Camera resolution Lens focal length Size of object Object contrast to background Object stance and motion

• Assessment Objective: distinguish (classify) between animal and crawling person with head facing camera

• Can better determine if a human is in standing position

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Alarm Assessment

Assessment Resolut ion (cont ’d.)

• Tests at Sandia showed that 8 pixels on a 30-cm target at a 30m far-field viewing width is minimum to classify human shape

• This affects number and placement of cameras• Recommend: Cameras be tested for specific application

Do not just rely on manufacturer’s data

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Alarm Assessment

Far F ie ld Resolut ion

• Examples of images from standard definition and high‐definition cameras

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760 x 480 pixel resolution 1376 x 1032 pixel resolution

Alarm Assessment

F ie ld of V iew and Resolut ion Test ing

• Camera far-field resolution adequacy is commonly measured in the field by using 30cm circle, triangle, and square geometric shapes

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Alarm Assessment

Addi t ional Camera Considerat ions

Photo courtesy of D

AV

ID M

cMA

HO

N

An exterior camera should be focused at dusk when there is the most red in the sky or at night with artificial illumination

Why? Focusing during daylight with a small

iris opening increases the depth of field

When the iris is open at night, looking through a larger diameter portion of the lens causes de-focus

Reds will not bend in a lens like visible light, causing de-focus at sunset

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Alarm Assessment

Spec ia l ized Lenses

• Different wavelengths (i.e., colors) can focus to different positions on detector

• Can result in color blurring on edges

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Apochromatic Elements – to accurately focus different wavelengths

StandardLens

APOLens



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V ideo Monitor

• Major types Black and white Color

• Flat Screen (LCD, Plasma, LED)• CRT

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Display resolution must be equal to or greater than camera resolution

Alarm Assessment

L ight ing

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L ight ing

• Function Illuminates scene for nighttime video assessment Allows camera to produce usable video Provides lighting for response personnel to see the situation and

the intruders

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Alarm Assessment

L ight ing Requirements

• Minimum lighting intensity 10 lux minimum

• Uniform illumination 6:1 light-to-dark ratio, maximum 4:1 design goal

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VIDEO



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Natura l L ight ing

Natural Lighting: Sunlight, moonlight, starlight Sun and moon light contain broadband visible and infrared light Broadband – all colors and wavelengths of visible light

• Spectral Response Changes at sunrise and sunset Intensity and angle changes by the time of day

• Effects shadows, color rendition, illuminating

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Alarm Assessment

Example: Uni form L ight ing

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Perimeter Isolation Zone Application



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Alarm Assessment

Ar t i f ic ia l L ight ing

Incandescent

Fluorescent

Mercury vapor

High pressure sodium

Low pressure sodium

Metal Halide

Light emitting diode (LED)

Near-IR

Compatible with camera type

Color vs. black and white

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Alarm Assessment

Camera Spectra l Response

• Illumination must match camera spectral response

589SodiumLine

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D ig i ta l V ideo Recorders (DVRs)/Network V ideo Recorders (NVRs)

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D ig i ta l V ideo Recorder Advantages

• DVRs and NVRs have significantly improved the process for recording security video and playback in the past 12 years DVRs and NVRs make VCR tape recorders obsolete They record images from 1 to 16 video cameras at the same

time The user can adjust the number of frames per second of video to

record and the resolution of video images stored

• DVRs and NVRs greatly improve the time required to access recorded video for playback Tapes do not have to be rewound to playback video

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What Is a DVR/NVR?

• Attributes of a DVR/NVR: Digital video capture and storage Reasonably fast processor and special software Large amounts of disk drive storage space Ability to connect to existing or network (IP) video cameras Stand alone box, integrated into a desktop computer or server

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These types of DVRs work independently, like a VCR

Examples o f In tegrated DVRs & V ideo Capture Cards

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Examples o f V ideo Recorder Sys tem E lements

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DVR–NVR Connect ion Di fferences

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Features/Capabi l i t ies

• DVRs/NVRs record video on computer hard-disk storage devices

• With a DVR/NVR you can Automatically record, organize and save days, weeks or months

of video depending on memory storage size Instantly playback video from a specific date and time Copy video clips and images to other storage devices Send an e-mail of alarm video to response force personnel Save large amounts of video possible because computer hard

drives are very large and not expensive

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Features/Capabi l i t ies (cont ’d.) These systems overwrite previously saved video when maximum memory

storage limit reached Can set up single or multiple camera images viewed as separate windows

on digital monitors Monitor views can be configured to display live and recorded pre-alarm

video DVRs/NVRs with Video Motion Detection (VMD) allow the DVR to

automatically store video when movement in the scene causes an alarm which triggers recording

User-friendly operation Because the DVR is computer-based, many setup and control parameters

can be customized for specific applications

Alarm Assessment

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Examples of different display configurations for DVR/NVR captured video scenes 85

Alarm Assessment

F rame Rate Example (5 fps)

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Most current DVRS/NVRs can capture video at 1 to 30 FPS

Reduced rate recording (3-5 FPS) when no movement detected

Record as many FPS as possible when an alarm is triggered

e Rate Example_5f



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Alarm Assessment

Image Qual i ty

• Image storage size can be controlled by increasing the amount of image compression

• Camera may initially capture a high resolution image, but images are compressed to save storage space

• Image is de-compressed for viewing video, but resolution can suffer• Image quality

controlled by Camera resolution Captured resolution Compression

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Alarm Assessment

Compress ion Example: “Low” Qua l i ty (~10 kB)

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Compress ion Example: “Medium” Qual i ty (~20 kB)

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Compress ion Example: “H igh” Qua l i ty (~40 kB)

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Alarm Assessment

• Camera type, lens, imager detector number of pixels, compression/bandwidth, monitor number of pixels all impact detection, classification, and identification values

• Linear process that can be constrained by any individual element

Alarm Assessment

V ideo Mot ion Detect ion (VMD)

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What Is VMD?

• Analysis of video from analog or digital cameras• Alarm video is captured, marked up, and stored• Detection algorithms for specific behavior alarms• Video from VMD can be stored on a DVR or NVR

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Alarm Assessment

VMD

• Significant advances in state of the art since 2000

A viable enhancement to video assessment

• Existing assessment cameras become an another intrusion detection sensor

• With alarm assessment cameras, VMD sensor’s infrastructure is already installed

• Camera video analyzed in real time for intrusions

• Video “marked up” with box around the moving target and may also have highlighted trail

• VMD software provides an alarm to alert operator of an intrusion and a log of alarm events

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Alarm Assessment

VMD Technology Attr ibutes

• VMD can be used with analog or digital cameras Effective with daylight, near-infrared, thermal imager

and 360-degree view cameras

Requires addition of hardware modules or alarm processing hardware and software

• Modular technology can be implemented at the camera or at the Central Alarm Station (CAS)

• In the camera configuration, VMD softwareis embedded into cameras with digital signal processor chips (DSP) and memory

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Alarm Assessment

VMD Technology Attr ibutes (cont ’d.)

• Digital camera can be configured to send low frame rate video during normal operation

• When intrusion detected, camera sends alarm message to the CAS and then increases frame rate during alarm event

• Pre-alarm video is stored in camera’s memory and transmitted to CAS when alarm event occurs

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Three Types of VMD Technology Avai lab le

• Software running on a PC with video capture card Located at or near CAS Analog or digital cameras connected to VMD

computer

• Standalone single- or multi-channel modules Located at camera or CAS Analog or digital cameras connected to VMD

modules Hardware/software complement

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Alarm Assessment

Three Types o f VMD Techno logy Ava i lab le (cont ’d .)• Software embedded in a digital camera with on-board

digital signal processor (DSP) & memory Inside digital camera at camera location

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With digital cameras having on-board video processors, analysis can be performed at the camera

With analog cameras analysis performed at the CAS



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Alarm Assessment

How VMD Works – Detect ion Rules

• Detection based on a set of rules and areas of interest Rules can be applied to areas of interest rather than entire view

Allows specific detection rules to be active only within portions of the camera’s field of view

• Movement in areas of interest triggers alarm

• Movement in other areas does not trigger alarm

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Alarm Assessment

VMD Sources of Nuisance Alarms

• Applications can create challenging environments Indoor environments produce fewer challenges than outdoor

environments Large changes in lighting, reflections from shiny objects, shaking

cameras, out of focus cameras, low contrast scene, target color near same color as background, target not occupying enough pixels in view, movement of large items in view (trees, large birds), blowing snow and driving rain

• Some VMDs produced no or very few alarms while others produced significant number of alarms

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Alarm Assessment

Assessment Zone Calcu lat ions

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Far Field

Assessment Zone

Near Field



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12m 30m(D2‐D1)

D1

D2

( FOV2 )

Alarm Assessment

Ca lcu lat ion for Zone Length

105

fl ‐ Focal Length of lens

Wi ‐Width of imager

FOV ‐Width of camera view at a distance (D)

D ‐ Distance from camera

Zone Length = D2 – D1

wi = 6.4 for 8mm (1/2 inch) format




( FOV1 )

Zone Length

Use to calculate HFOVand distance to camera D = FOV x fl

Wi

D FOVWi fl

D1 = FOV1 x flWi

D2 = FOV2 x flWi

Near-Field

Far-Field

D flFOV Wi

:

Alarm Assessment

Geometry of Assessment Zone

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800 pixels across

30 m across

Far-Field

Near-Field

Another way to calculate is using ratios:

8 pixels to 30 cm = 800 pixels to X

8 px = 800 px

30 cm X

Solve for X = 30 m

30 cm at 8 pixels = 3.75 cm per pixel

If a camera/monitor provides 800 pixels of horizontal resolution, then maximum field of view width is:

3.75 cm x 800 pixels = 3000 cm = 30 m

What if the camera imager was 1000 pixels?

Alarm Assessment

Resolut ion at Far F ie ld

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Alarm Assessment

Camera V iew Geometry for In ter io r Assessment

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Top View Side View



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Summary

• Alarm assessment ends the alarm detection function by determining the cause of a sensor alarm

• Assessment may be performed using response force / security guards or camera video alarm assessment

• Response force assessment includes: Sufficient trained personnel in appropriate locations Sufficient lighting Effective communication

• Camera video assessment includes: Camera, lens, lighting and video control system

• Video assessment system must provide complete coverage and display of sensored areas at all times

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Documents

12. Alarm Assessment - Sandia National Laboratories12 - Alarm Assessment The Twenty-Sixth International Training Course Page 2 Alarm Assessment INFCIRC 225 Revision 5 Recommendations