Figure 13

(a)–(d) Watermarked images after embedding 256 × 256 watermark image as shown in Figure 11(b). (e)–(h) Extracted watermarks from (a)–(d), respectively. (i)–(l) Watermarked images after embedding 256 × 256 watermark image as shown in Figure 11(d). (m)–(p) Extracted watermarks from (i)–(l), respectively. (a)PSNR: 48.27 dB (b)PSNR: 48.47 dB (c)PSNR: 47.94 dB (d)PSNR: 47.63 dB (e)γ = 0.9975 (f)γ = 0.9966 (g)γ = 0.9971 (h)γ = 0.9965 (i)PSNR: 48.84 dB (j)PSNR: 49.11 dB (k)PSNR: 48.66 dB (l)PSNR: 48.26 dB (m)γ = 0.9972 (n)γ = 0.9967 (o)γ = 0.9969 (p)γ = 0.9963