GNEMS & JVSG - A professional CCTV Designing software. Theory and applications

Kounis A Georgios, PhD

AMP MOBOTIX since 2013.

JVSG Partner since 2012.www.gnems.gr

[email protected]

Tel. +30 222 1 302129

Buy Product Here:

http://www.jvsg.com/gr/

Basic Characteristics of CCTV Systems CMOS size(w x h in mm)

1/4 inch 3.20mm H x 2.40mm V

1/3 inch 4.80mm H x 3.60mm V

1/2.5 inch 5.70mm H x 4.28mm V

1/2 inch 6.40mm H x 4.80mm V

2/3 inch 8.80mm H x 6.60mm V

1 inch 12.7mm H x 9.60mm V

Lens focal length (Fw)

Lens field of View (View angle φ)

Width of FoV (W in m)

Height of FoV (H in m)

Maximum distance of lens from FoV (D in m)

CMOS Analysis (CCDw x CCDh pixels)

Fw

D

w

h

H

W

φ

CMOS

FoV

LENS

CCTV CAMERA

Fw

D=

CCDhH

= CCDw

W⟹ D =

Fw 𝑥WCCDw

tan𝜑

2=

W

2D

DIN EN 50132-7 Prototype

Monitor 12.5 px/m

Detect 25 px/m

Observe 62.5 px/m

Recognize 125 px/m

Identify 250 px/m

Verify 1000 px/m

These parameters can be used to

determine the maximum distance

between the camera and the supervised

area ( position) , the minimum resolution

to match the position of the camera,

and the most suitable camera lens for

optimal coverage of the surveillance

area

o The question whether a video image is usable

or not depends on the purpose of the system.

This can range from the ability to simply

perceive a change in the context to the

reliable identification of a person who willstand up in court.

o As defined in the standard DIN EN 50132 - 7,

there are now six different levels of quality for

video surveillance . "Verify " is the level with the

highest requirements for image quality , while

"Monitoring" is the one with the lowest.

DIN EN 50132-7

Allows an observer to identify the position, direction and speed with which a

person moves, provided that the area in which the person is expected, it is

known, before the person enters the area.

Allows an observer to find, with almost absolute certainty, that person in any

position in the surveillance area. Under these conditions, a video sensor

could be used as an alarm sensor.

Allows an observer to reconstruct the actions of individual persons with

almost absolute certainty in any position in the surveillance area.

According to this level, an observer could almost certainly be able to

recognize a person who knows.

Reproduction of data is so good that an observer can almost certainly

identifies a perfect person who does not know the basis of the video image.

Reproduction of data is so good that an observer can almost certainly be

perfectly identifies a person who not only know the basis of video and poor

contrast situations.

Monitor 12.5 px/m

Detect 25 px/m

Observe 62.5 px/m

Recognize 125 px/m

Identify 250 px/m

Verify 1000 px/m

Hemispherical camera with 180 °

horizontal angle of the picture Thanks to the hemispherical lens 180 °, a single camera can

monitor an entire room right from corner to corner - and isprimarily suitable to provide an excellent review and less

suitable for more precise details.

Humans, for example, may be identified very well at

distances up to 1,5 m, and with sufficient detail at up to 3 m.

Objects can be recognized even at distances of 5 m and

more from the camera.

If one wanted only to know if people enter a room, or to

monitor specific objects, rooms with surface up to 100meters. can be monitored using a single camera.

Examples of calculation use

Looking to have imaging field range of 5 meters

at a resolution which provides recognition at a

distance from the camera 20 meters

MOBOTIX CAMERA CCD 1 / 2.5 ''.

625= 5m * 125px/m

640x480 px most realistic resolutions

13ο the closest lens angle near 14 calculated

𝜑

2= tan−1

W2D ⟹ 𝜑 = 2 tan−1

W2D = 2 * tan−1

52∗20

=

2*7.12 = 14ο

1/2.5 inch 5.70mm H x 4.28mm V

L135-L160 the closest lens with a focal length close to 23.7 mm

Recognize 125 px/m

Fw= CCDw 𝑥D

W22.8mm

What If we have to do calculation

for:

More camera

Calculate installation height and FoV height

Work with different cameras

Want to demo the cameras FoV for the real surround

Demo the EN50132-7

Calculate the total bandwidth and total Hard Disk space based on

scenario as % of movement

Present 3D imaging of FoV or use images of the field form Google

Earth or even wish to add topographic map of the are under investigation