User's Manual

Scanner

Epson Perfection

The scanners have a variety of buttons on their front panels. None of these buttons interact with the AFHCAN software, so they are not described here. Model 1650 does not have a power switch, but the other three models do. As installed on the AFHCAN Cart, the scanner power switch is not readily accessible. It is the standard practice on the AFHCAN installation to leave the scanner power button on at all times and to control power to the scanner via the Cart’s main power switch. This power distribution strategy applies to most other devices on the Cart. For exceptions, refer to device-specific modules in this binder for details.

1.1.1 Functional Description

The scanner is used to scan paper documents, photographs, or other items into a case. The AFHCAN software activates a TWAIN driver, which is software that comes with the scanner.2 The TWAIN driver controls the operation of the scanner.

The AFHCAN software and the TWAIN driver interact differently depending on which scan mode is selected. The AFHCAN software offers two scan modes:

black and white (Scan button)

color (Scan Color button)

In black and white mode (Scan mode), the AFHCAN software directs the TWAIN driver to scan in black and white. Each pixel is forced to be either white or black (in other words, shades of gray are lost). This is useful when scanning black and white forms or other documents where high contrast is a plus. The downside is that if there are items which are lightly shaded, those items may be dropped, and the overall image resolution may appear to be diminished. In Scan mode, a small window appears indicating that a scan is underway. Scan mode saves files in a PNG image format.

In the Scan Color mode, the TWAIN software performs the following steps:

previews the image to determine the type of image, image area, and image characteristics

automatically adjusts the image resolution, size, and other attributes

scans the image and saves it in a JPG image file format

sends the image file to the AFHCAN software for inclusion in a case

When running on a Cart, the software resets the TWAIN driver to factory defaults each time the AFHCAN software is started. This places the TWAIN driver in automatic mode.

Note: When the software is running on a PC workstation, the reset does not take place, which means the TWAIN driver will open in the same mode and with the same settings that were in effect when the software was last used.

In automatic mode, the preview is analyzed to determine the type of image, the image area, and any optimal settings. The TWAIN software distinguishes the types of images listed in Table 1.

2The term TWAIN refers to software that fits between the user application and a device (scanner, camera, etc.) TWAIN drivers make it easier to standardize the integration and control of various devices on a computer system. For more information on TWAIN, go to www.twain.org.

PUB-119 Rev B.doc

2