User Guide

Operating VRS
VRS User’s Manual
71
documents in 8-bit grayscale, but convert these images to single bit or pure black and
white images before sending the images to your application.
In this example, we will scan a document and show the effects of VRS Contrast,
Brightness, and Gamma settings on it. In the image shown in Figure 2-32, we have
scanned a document we will refer to as the “CORE” document as a black and white
image at 200 DPI. If we first set the Contrast value to 0, then set the Brightness value
to 12 (remember that setting the Contrast to 0 is basically like using VRS as a simple
thresholding device), the faint text on the top of the page is visible, but the text behind
the highlighter is unreadable.
Figure 3-31. Brightness with a Low Setting
This text is
revealed.
This text
disappears.