Xerox xerox documate manual Initialize White Level From Document, Black Level

Scanning from TWAIN and WIA

Initialize White Level From Document

Automatically detect and adjust the white level using the leading edge of the scanned item. This is a feature that uses the scanner for processing and it is available whether or not Visioneer Acuity is installed. However, please note that there will be a black line at the top of each image. This is where the scanner starts the image capture as the reference point for it to detect and set the background as white in the image.

When Visioneer Acuity is installed, we recommend you use Remove background if you want to have the background automatically removed without seeing this black line.

White Level

With this option you can set what the scanner should interpret as “white” in the final image, even though the page being scanned may have a shaded or off-white background. You may want to adjust this option to have the image automatically corrected when you are scanning irregular paper, such as thick or thin paper, that may cause the white page in the final image to appear shaded with a pale grey. This option is only available when scanning in Color or Gray.

For the best automatic results you can simply select the type of paper you are scanning from the list. Alternatively, you can input a number in the Custom value field. The value you set in this field can be from 128 to

255.If you set the custom value to 128 you are telling the scanner that all pixels that are grey level 128 or higher (lighter) should be changed to white in the final image. If you set the custom value to 255, you are telling the scanner that only pure white is white and anything lower than 255 should remain unchanged in the final image.

Black Level

With this option you can set what the scanner should interpret as “black” in the final image. If you are scanning items that have notes written with a pencil, you may want to raise the black level to have the pencil notes appear black in the image. You can set a value for black from 0 to 127. If you set this value to 127, you are telling the scanner that all pixels that are grey level 127 or lower (darker) should appear as black in the final image. This option is only available when scanning in Color or Gray.

Xerox® DocuMate® 4790	7-151
User’s Guide