QAID # 3276 Published
Question / Problem:
How to set up a scanner as a "compatible" VRS scan source
Answer / Solution:
Kofax prefers customers to use "certified" scanners with all VRS products. This ensures that the scanner has been configured with VRS to provide optimum image quality, and that it has been tested extensively with the required driver and no major issues are known.
However, some non-certified scanners can be configured with VRS in "compatible" mode. There are 2 important items which the scanner MUST meet in order to work with VRS:
- The scanner must output 256-level Grayscale (also known as 8-bit Grayscale) data. When an application requests a bitonal image, VRS will instruct the scanner to proovide a Grayscale image. This image is then used by VRS to produce the clear and crisp bitonal output image which is sent to the scanning application.
- The scanner must provide either an ISIS or TWAIN driver. An ISIS driver is preferred as this allows VRS to better control the scanner. Some TWAIN drivers will work with VRS but others do not. WIA drivers are not supported for use with VRS in "compatible" mode.
Assuming a scanner meets this criteria, the scanner should be able to be configured with VRS in a "compatible" mode. However, a little more work is required in order to setup a "compatible" scanner:
- During the installation of VRS select the "Do not configure..." option below the list of certified scanners.
- Install the appropriate scanner drivers.
- Use the Scanner Configuration Utility (VRS 4.x) or the VRS Administration Console's Scanner Configuration screen (VRS 5.x) to configure the appropriate sources for the scanner. If a TWAIN or ISIS application will be used one of the Sources which use one of the "with SVRS" Source Types, MUST be set as the "default" source. This allows the Kofax Software VRS - TWAIN and Kofax Software VRS - ISIS drivers to know which scanner to communicate with.
- The Brightness, Contrast, and Gamma settings in the VRS Interactive Interface must be adjusted in order to get adequate image quality. All of this information is detailed the VRS Installation Guide and the VRS Interactive Viewer Help included with the product and provided via the Kofax VRS Product Documentation pages.
Even after all this is done the same level of Image Quality you would expect from a "certified" VRS scanner can not, most likely, be obtained. The reason is that unique VRS settings are determined for each "certified" scanner so that they provide the optimum image quality. In addition, each certified scanner model is run through a series of tests in order to verify they function correctly with VRS.