FPGA Implementation of Digital Images Watermarking System Based on Discrete Haar Wavelet Transform

Table 4

NC and PSNR values for watermarked, decrypted and attacked images by median filter.

Window size	PSNR				NC
	Cameraman	Mandrill	Lena	Pepper	Cameraman	Mandrill	Lena	Pepper
2×2]	29.64	26.80	29.55	29.56	1	1	1	1
3×3]	36.52	29.80	35.30	35.12	1	1	1	1
4×4]	28.81	25.05	28.89	28.45	0.874	0.812	0.898	0.856
5×5]	31.07	24.61	31.23	31.02	0.771	0.754	0.780	0.756
6×6]	27.36	22.92	27.77	27.48	0.529	0.524	0.551	0.531
7×7]	27.10	22.61	29.03	28.45	0.517	0.512	0.535	0.530
8×8]	25.28	21.88	26.78	25.07	0.371	0.331	0.348	0.312
9×9]	25.31	21.82	27.66	24.69	0.114	0.103	0.135	0.175