video detection sensor for vehicle presence

THETHE ReferenceReference in Traffic Video Detectionin Traffic Video Detection1

Video Detection Sensor for Video Detection Sensor for Vehicle PresenceVehicle Presence

Basic Principles, Selection, Installation & Basic Principles, Selection, Installation & ConfigurationConfiguration


Video detection: Detection Video detection: Detection zones on video imagezones on video image

TrafiCam: TrafiCam: Vehicle presence Vehicle presence detectiondetection

Detection output Detection output generationgeneration


Basic functionality = vehicle presence

Alternative functionality

= count (number of pulses)

= zone occupancy (length of pulses)

FunctionalitiesFunctionalities


TrafiCam “Wide Angle” (focal distance = 3mm):

o Detection at close range (close range (0-25m0-25m)), with a wide camera viewo Rather vertical camera positiono Typical camera height:

o side fired: 3,5-8m o overhead: 5-8m TrafiCam “Narrow Angle” (focal distance =

8mm):o Detection at a longer distance (longer distance (15-75m15-75m)), with a wide camera view, but zoomed ino More horizontal camera positiono Typical camera height:

o side fired: 8-12mo overhead: 6-10m

Selection: 2 lens types Selection: 2 lens types availableavailable


Camera View TrafiCam Camera View TrafiCam “Wide Angle”“Wide Angle”

0-25m

4 lanes


Camera View TrafiCam Camera View TrafiCam “Narrow Angle”“Narrow Angle”

15-75m

4 lanes


Wide Angle

Narrow Angle

TrafiCam Wide Angle vs TrafiCam Wide Angle vs Narrow AngleNarrow Angle


Example TrafiCam Example TrafiCam Wide AngleWide AngleThree lanes, stop bar detection, TrafiCam overhead at 6m height


Example TrafiCam Example TrafiCam Narrow AngleNarrow Angle

Three lanes, advance detection, TrafiCam overhead at 8m height


InstallationInstallation

no horizon in the image


be aware of optical occlusion!

- on the same lane- on adjacent lanes

5m camera height, no offset

9m camera height, no offset

5m camera height, 2m offset

Offset = distance from the edge of the road



vertical or horizontal mounting

Mount on solid infrastructure

Fixation with bolts or (stainless steel) bands

Try to avoid camera movement. This could decrease the detection performance!



Examples Vertical Examples Vertical MountingMounting


Example Horizontal Example Horizontal MountingMounting


Example Alternative Example Alternative MountingMounting


ConfigurationConfigurationoptimal size of detection

zone = slightly exceeding size of a

regular carMultiple

detection zones per

lane possible to cover a larger areaSize regular car: about

2m wide & 5m long


Direction sensitivity

Make a zone direction

sensitive only to avoid unwanted

detectionsA direction sensitive zone could decrease the detection performance

ConfigurationConfiguration


Vehicle headlights in detection zone

detection during daytime: on vehicle detection

at night: on vehicle headlights



Advanced settings: Use headlight reflection suppression only

when strong reflections are expected

Use tree shadow suppression only when strong tree shadows are expected

Use camera movement suppression only when significant camera shaking is

expected



Traficon nv

Tel.: +32 (0)56 37 22 00

Fax: +32 (0)56 37 21 96

E-mail: [email protected]

www.traficam.com

video detection sensor for vehicle presence

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