JAI VISCAM 1000 System, Руководство по установке

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VISCAM 1000 Systems
28 System Set-Up
Retrigger Delay - This setting determines the minimum number of frames between two consecutive triggers.
The actual time can be calculated as the number of frames multiplied by the frame-rate selected in the Trigger
Sync mode setting. If multiple triggers occur within this time then only the first trigger will be accepted. The
purpose for this setting is to minimize the number of “multi triggers” where the same vehicle generates
multiple triggers but only a single image is needed to identify the vehicle.
Lane Empty – This setting is essential to the “Rear Shot” Lane Direction mode (explained below). This specifies
the maximum number of “empty” frames the triggering system is allowed to wait in order to make sure that
the vehicle has left the detection area. If this value is too low then a lot of multi-triggers will be generated. If
it is too high then it limits the ability to detect tail-gating vehicles (in case the tail-gating vehicle is closer to
the vehicle in front than the number of frames specified). Default value is 11 and it is recommended to keep
this maximum value whenever possible.
Lane Configuration - This selection has the choice of
Single Lane
and
Dual Lane
. In Single Lane, the Vehicle
Detector algorithm uses the whole Vehicle Detection Area to detect a vehicle. In Dual lane, the image is
divided in half and each half is used to detect vehicles. Thus, if a vehicle happens to be crossing between
lanes, there may be an instance, where the same vehicle may be triggered in both lanes.
Lane Direction – This selects the way the Vehicle Detector triggers are generated. In “Rear Shot” mode the
vehicles will be travelling away from the camera and the triggers are generated when the vehicle leaves the
detection area. In “Front Shot” mode the vehicles will be travelling towards the camera and the triggers are
then generated when vehicles enter the detection area.
Detection Grid – It is possible to enable/disable the Vehicle Detection in each of the 9 grids of the detection
area. It is recommended to disable the middle (Grid 5) in dual-lane configuration. This will minimize the
number of multi-triggers that might occur if the passing vehicles get too close to the middle detection zone
(which is shared between both left and right lane).
4.10.2 Visualization helper for Vehicle Detector and ALC setup
The camera can superimpose the Vehicle Detection Area and ALC Area onto the image to help during trigger
line setup. To enable visualization enable them in “Debug Output Mask”:
1. On Image Graphics (Vehicle Detector): to show Vehicle Detection Area
2. On Image ALC Area: to show ALC Area.
Figure 30. VD and ALC visualization settings
*Be sure to disable the graphics when finished. They appear in the final image!
Figure 31. The visualization as displayed in image
Vehicle Detection Area (green boxes):
1. Each box represents 1 detection grid. There are 2 groups: left lane and right lane.