A Strong Robust Zero-Watermarking Scheme Based on Shearlets’ High Ability for Capturing Directional Features

Table 6

The values of distorted host images and values of extracted watermarks under Salt and Pepper noise.

Host; image
	SSIM/NC	SSIM/NC	SSIM/NC	SSIM/NC	SSIM/NC
Boat	0.97/1.0000	0.88/0.9993	0.78/0.9961	0.38/0.9922	0.21/0.9393
Goldhill	0.98/0.9993	0.89/0.9967	0.79/0.9889	0.38/0.9723	0.20/0.9237
Baboon	0.98/0.9961	0.91/0.9711	0.85/0.8992	0.50/0.7856	0.32/0.8135
Barbara	0.98/0.9993	0.90/0.9993	0.81/0.9980	0.43/0.9928	0.26/0.9928
Peppers	0.97/1.0000	0.87/0.9993	0.76/0.9993	0.33/0.9830	0.17/0.9381
Man	0.98/0.9967	0.89/0.9830	0.79/0.9777	0.38/0.8949	0.21/0.8662