Cryptography Reference
In-Depth Information
(a)
(b)
(c)
(d)
Fig. 11.9.
The JPEG compressed watermarked images. (a) QF = 100%. (b) QF =
80%. (c) QF = 50%. (d) QF = 30%.
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Fig. 11.10.
The watermarks extracted from JPEG compressed watermarked im-
ages. (a) The robust one from Fig. 11.9(a), NHS = 0.999. (b) The semi-fragile one
from Fig. 11.9(a), NHS = 0.990. (c) The robust one from Fig. 11.9(b), NHS = 0.988.
(d) The semi-fragile one from Fig. 11.9(b), NHS = 0.874. (e) The robust one from
Fig. 11.9(c), NHS = 0.968. (f) The semi-fragile one from Fig. 11.9(c), NHS = 0.663.
(g) The robust one from Fig. 11.9(d), NHS = 0.937. (h) The semi-fragile one from
Fig. 11.9(d), NHS = 0.400.
