A Robust Fractal Color Image Watermarking Algorithm

Table 4

Comparing the proposed method with Tsui at al. [15], Kutter et al. [12] and Cox at al. [5] methods.

Attacks	Tsui et al. [15]	Kutter et al. [12]	Cox et al. [5]	Proposed
Attack free	1.0	0.9476	0.9957	1.0
Median filter (3×3)	0.9877	0.8750	0.9146	0.9936
JPEG
10	0.4237	N/A	0.6889	0.7001
50	0.9302	0.3504	0.9396	0.9401
Gaussian noise (𝜎=20)	0.5038	0.4788	0.4516	0.5124
Scaling (factor 2)	0.8743	0.8500	0.8460	0.9633
Sharpening	0.9781	0.8893	0.9405	0.9872
Bluring	0.9650	0.8956	0.9463	0.9847
Cropping	0.6981	0.6330	0.5954	0.6990