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I 54 INTELLIGENT COMMUNICATION SYSTEMS
FIGURE 12.4 Threshold.
FIGURE 12.5 Dither Method.
Given the element of a dither matrix T(i,j), the value of pixel g r(i,j) is deter-
mined as follows.
An example is shown in Figure 12.6.
12.2.7 Multivalue Dither Method
In addition to the binary dither method, the three-value and four-value dither
methods have been proposed. These are extensions of the binary dither method. In
the three-value dither method, a value of a half-level is taken into consideration.
