JAI VISCAM 1000 System, Руководство по установке

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System Set-Up 33
VISCAM 1000 Systems
4.13 Solar Position Control for assisting the ALC
The ALC mode works well for in-image auto determination of gain and exposure time. There are situations
though in which the sun’s position makes it difficult to adjust the image properly.
Examples:
- The Sun is in front of the vehicle so that the plate is in the vehicle’s shadow but the road is bright. The
exposure and gain setting will make the plate dark.
- The Sun is directly behind the vehicle, and the plate’s retro-reflectivity will make it extremely bright.
The camera will be able to compensate for this if it can calculate the sun’s position. You can enable and
configure these controls in the Solar Position Control section.
For more details please see the Solar Position Control Application Note.
Solar Position Control: Enable or disable the Solar Position Control assistance for the ALC.
Camera Location Latitude and Longitude: The camera location is specified as a combination of the Latitude and
Longitude. The Latitude value is in “decimal degrees” where a positive value is degrees above equator (north)
and a negative value is degrees below equator (south). The Longitude is also specified in decimal degrees
where a positive number is degrees east of the “Prime Meridian - Greenwich” and a negative number is degrees
west of Greenwich. A good source for the location coordinates could be either from a GPS – or from reading the
location from various map sources.
1. Camera and vehicle directions:
a. Cameras Direction (Azimuth) is specified as the compass direction that the camera is facing,
where 0 degrees is “true north” and 180 degrees is when the camera is facing directly south.
b. Camera Tilt is the angle the camera is “tilted” down from the horizon. This angle is typically
between 25 degrees to 30 degrees.
c. Vehicle direction (or road direction) is the direction that vehicles will be travelling away from
the camera. This value is typically the same value as the camera azimuth (in gantry mounted