Steganography in Halftone Images - Visual Cryptography and Secret Image Sharing - page 365

1.2

T=5
T=10
T=15
Theoretical value

1

0.8

0.6

0.4

0.2

0

−0.2

0 50 100 150 200 250 300

R w- w a i y of X

FIGURE 13.21
Contrast of Y in Figure 13.18 vs row-wise average intensity of X in Figure
13.14 ( Ramp).

300

Y1
Y2

250

200

150

100

50

0

0 50 100 150 200 250 300

R w- w a i y of X

FIGURE 13.22
Row-wise average intensity of Y 1 in Figure 13.4 and Y 2 in Figure 13.9 vs
row-wise average intensity of X in Figure 13.14 (Ramp).