Kodak i55 - Manual (Page 40)

36 A-61527 May 2006
Scanning bi-tonal images Bi-tonal images are scanned images that are made up of only black-
and-white elements. The descriptions below are for bi-tonal images
only.
Binarization is the process of converting a grayscale or color image to
a bi-tonal image. There are several different methods of performing this
conversion. Two of the options Kodak provides are iThresholding and
Adaptive Threshold Processing.
These options are applied to grayscale scanned images and output a
bi-tonal electronic image. Thresholding and Adaptive Threshold
Processing separate the foreground information from the background
information even when the background color or shading varies, and the
foreground information varies in color quality and darkness. Different
types of documents may be scanned using the same image processing
parameters and still result in excellent scanned images.
• iThresholding: selecting iThresholding allows the scanner to
dynamically evaluate each document to determine the optimal
threshold value to produce the highest quality image. This allows
scanning of mixed document sets with varying quality (i.e., faint text,
shaded backgrounds, color backgrounds) to be scanned using a
single setting thus reducing the need for document sorting.
When using iThresholding, only Contrast may be adjusted.
• Adaptive Thresholding (ATP): the Adaptive Threshold Processor
separates the foreground information in an image (i.e., text, graphics,
lines, etc.) from the background information (i.e., white or non-white
paper background).
When using Adaptive Thresholding, Threshold and Contrast may be
adjusted.