Figure 29

(a)–(h) The watermarked image after different composite attacks, (i)–(k) The extracted watermark from (a)–(h), respectively. (a)PSNR = 31.17 dB Wiener filter (3 × 3) + Scaling (1/2) + JPEG(80) (b)PSNR = 27.08 dB Softthreshold + Blurring (1) + JPEG(85) (c)PSNR = 24.46 dB Hardthreshold + Averagefiltr (3 × 3) + JPEG(80) (d)PSNR = 24.60 dB Templateremoval + Scalin (1/2) + JPEG(85) (e)PSNR = 31.22 dB Blurring (2) + JPEG(80) (f)PSNR = 32.14 dB Median filter (3 × 3) + JPEG(85) (g)PSNR = 26.48 dB Sharpening (1) + JPEG(90) (f)PSNR = 24.59 dB Blurring (2) + JPEG(80) (i)γ = 0.8768 (j)γ = 0.7999 (k)γ = 0.7472 (l)γ = 0.7472 (m)γ = 0.6889 (n)γ = 0.7560 (o)γ = 0.7983 (p)γ = 0.4247 (p)γ = 0.8098