Post on 16-Jul-2015
Kounis A Georgios, PhD
AMP MOBOTIX since 2013.
JVSG Partner since 2012.www.gnems.gr
info@gnems.gr
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