VIVOTEK
User's Manual - 69
The inclusive window refers to the “weighted window“; the exclusive window refers to “ignored
window“. It adopts the weighted averages method to calculate the value. The inclusive windows
have a higher priority. You can overlap these windows, and, if you place an exclusive window
within a larger inclusive window, the exclusive part of the overlapped windows will be deducted
from the inclusive window. An exposure value will then be calculated out of the remaining of the
inclusive window.
Include
Exclude
Weighted region
Ignored region
Include
Exclude
■
HLC
: (Highlight Compensation). Firmware detects strong light sources and compensates on
affected spots to enhance the overall image quality. For example, the HLC helps reduce the
glares produced by spotlights or headlights.
■
BLC
(Back Light Compensation): This option will automatically add a “weighted region“ in the
middle of the window and give the necessary light compensation.
■
Auto:
Firmware automatically determines an optimal exposure level.
■
Flickerless:
Under some circumstances when there is a difference between the video capture
frequency and local AC power frequency (NTSC or PAL), the mismatch causes color shifts or
flickering images. If the above mismatch occurs, select the
Flickerless
checkbox, and the range
of Exposure time (the shutter time) will be limited to a range in order to match the AC power
frequency. When selected, the exposure time will be forced to stay longer than 1/120 second.
For cameras that come with fixed iris lens, setting the exposure time to longer than 1/120 second
may introduce too much lights to the lens. Users can use this option to observe whether the
result of long exposure time is satisfactory.
You can click and drag the semi-circular pointers on the
Exposure time
and
Gain control
slide
bars to specify a range of shutter time and Gain control values within which the camera can
automaticallly tune to an optimal imaging result. For example, you may prefer a shorter shutter
time to better capture moving objects, while a faster shutter reduces light and needs to be
compensated by electrical brightness gains.
