DRI in Video Surveillance
Wish you a very happy new year 2018. In today’s competitive
environment, having new customers constantly is one of the keys of
success. To make professional quotes with proper sketches, realistic test
objects, 3D images, mock ups etc, which leave a lasting impression on your
clients.
When you are answering queries related to your product, you can
quickly glance through the details while your client is on call.
DRI stands for Detection, Recognition and Identification in video
surveillance. DRI ranges, expressed in meters, km (or miles), can be found in
the specification table of infrared camera brochures. In order to select the
right sensor meeting the application requirements, these DRI ranges have to be,
first, perfectly defined, but also assessed with regards to globally adopted
industrial standards.
DRI Definition
The terms “Detection”, “Recognition” and “Identification” were
defined as follow:
- Detection:
ability to distinguish an object from the background
- Recognition:
ability to classify the object class (animal, human, vehicle, boat …)
- Identification:
ability to describe the object in details (a man with a hat, a deer, a
Jeep …)
The following pictures illustrate these definitions:
Left image: Detection – At several kms, 2 targets are
detected out of the background
Center image: Recognition - a human is walking along
the fence
Right image: Identification – 2 males with trousers
and jackets are identified – one is smoking.
We detect an object when it enters the field of view. Detection
means we are aware that an object (or person) now exists where previously it
was not seen. Usually, this is due to movement of the object into the field of
view of the surveillance camera. Detection simply means we are aware of the
object, but have too little details to recognize or identify the object.
As the object moves closer, we may recognize the object from
characteristics previously encountered. For example, aircraft recognition is
taught to military ground troops and airmen. All aircraft have wings, engines,
a fuselage, and tail assembly. They differ in size, shape, number, and position
to each other. A particular model of aircraft can be recognized by recalling
these characteristics from pictures, drawings or past detailed observations.
Identification is the process where sufficient details are
available to uniquely discern a person or object that is previously unknown.
Identification requires sufficient detail to accurately describe or recall the
characteristics of the subject at a later time. For example, a mug shot
(booking photograph) is taken following the arrest of a subject as a means of
photographing (recording) sufficient details for later identification by a
victim or witness. In video surveillance terms, sufficient detail is calibrated
in pixels per foot of the area recorded by the camera.
DRI Ranges
“A picture is worth a thousand words” goes the old and equally wise
saying. It is true that most human beings learn much quicker when aided by
visuals rather than pure text as that is more in tune with the human psychology
of learning.
So instead
of remembering commands and functions you will easily remember that yellow
color indicates areas where it is possible to recognize people, red color
indicates areas suitable for people identification, green areas for detection
and so forth.
To put this
in perspective, sensors have a resolution of 640×480 which is over 300,000
pixels.
Human “detection” only requires 3.6 of those pixels and “identification” only requires 230 pixels, which is an extraordinarily small amount on the screen that can easily go unnoticed by the human eye. In fact, if this page were the size of your video feed, the area required for a human detection rating is about equivalent to a lowercase letter “i” in this text. The amount of detail visible at the detection, recognition and identification distances is not as high as one might expect, as can be seen in the chart below.
Human “detection” only requires 3.6 of those pixels and “identification” only requires 230 pixels, which is an extraordinarily small amount on the screen that can easily go unnoticed by the human eye. In fact, if this page were the size of your video feed, the area required for a human detection rating is about equivalent to a lowercase letter “i” in this text. The amount of detail visible at the detection, recognition and identification distances is not as high as one might expect, as can be seen in the chart below.
Another
thing that is often not mentioned is that these ratings are based on what is
termed “ideal conditions” which rarely happen in the real world. The average
environmental application will get 25% less than the distance that the thermal
camera is rated for and in extreme conditions can be less than 10% of the rated
distance.
Based on SR-100 & SR-100P by FLIR the approximate DRI (Detection, Recognition and Identification) range for a vehicle and a human target is listed in Tables 1 & 2.
Based on SR-100 & SR-100P by FLIR the approximate DRI (Detection, Recognition and Identification) range for a vehicle and a human target is listed in Tables 1 & 2.
Lens
|
Detection
|
Recognition
|
Identification
|
100mm
|
4.4km
|
1.1km
|
580m
|
Table 1: DRI
range for Vehicle with 2.3m critical dimension using a Thermal Security Camera
with 38 micron pitch detector
Lens
|
Detection
|
Recognition
|
Identification
|
100mm
|
1.6km
|
400m
|
200m
|
Table 2: DRI
range for Human Target using a Thermal Security Camera with 38 micron pitch
detector
Assumptions: 50% probability of achieving objective at the
specified distance given a 2-degree
temperature difference and 0.85/km atmospheric attenuation factor. Actual range may vary depending on camera
setup, user experience, environmental conditions, and type of monitor or
display used.
Each &
every Camera has this DRI ranges, before preparing project oriented ppt, do
confirm the ranges & show in a slide with sketch.
Artical publish at safe secure magazine January 2018 issue.
Warrior 2.0 26BF2 is a 1080P 2MP Fixed Lens Mini Bullet Camera
Detect: 100 ft
Recognize: 50 ft
Identify: 25 ft
Recognize: 50 ft
Identify: 25 ft
Laser 2.0 - 26ZV-LIR is a 2MP
(1080P) IP PTZ Camera with 33x Optical Zoom & Laser Infrared camera and Spotlight 2.0 - 26ZV-W is a 2MP (1080P) IP PTZ
Camera with 22x Optical Zoom & Full Spectrum Light Camera
Detect: 950 ft
Recognize: 875 ft
Identify: 750 ft
Recognize: 875 ft
Identify: 750 ft
Lookout
2.0 - 26ZV is a 2MP (1080P) IP PTZ Camera with 30x Optical Zoom Camera
Detect: 1000 ft
Recognize: 900 ft
Identify: 800 ft
Recognize: 900 ft
Identify: 800 ft
Judge 8.0 - 26DV8 is a 4K
(8MP - 4x1080P) Multi-Purpose Lens Dome Camera with Motorized Zoom and IK10
Camera and Gladiator 8.0 - 26BV8 is a 4K (8MP - 4x1080P) Multi-Purpose Lens
Bullet Camera with Motorized Zoom and P-Iris Camera
Detect: up to 200 ft
Recognize: up to 150 ft
Identify: up to 100 ft
Recognize: up to 150 ft
Identify: up to 100 ft
Deputy 4.0 - 26DF4 - 4MP
(2x1080P) Fixed Wide Angle Lens Turret Dome Camera
Detect: 115 ft
Recognize: 50 ft
Identify: 35 ft
Recognize: 50 ft
Identify: 35 ft
Archer 2.0 - 26BV2-L - 2MP
Long Range, Low Light Bullet Camera with Motorized Zoom and Focus
Detect: up to 450 ft
Recognize: up to 350 ft
Identify: up to 300 ft
Recognize: up to 350 ft
Identify: up to 300 ft
Warrior 4.0 - 26BF4 is a 4MP (2x1080P) Fixed Lens Mini Bullet
Camera
Detect: 150 ft
Recognize: 75 ft
Identify: 50 ft
Identify: 50 ft