Application of Fractional Wave Packet Transform for Robust Watermarking of Mammograms

Table 2

Correlation coefficients of extracted watermarks (β = 1).

Attack	mdb001; PSNR	Correlation coefficient	mdb017; PSNR	Correlation coefficient	mdb054; PSNR	Correlation coefficient	mdb153; PSNR	Correlation coefficient
No attack	51.9226	0.99167	52.1666	0.9911	52.1268	0.9863	50.5253	0.9990
Weiner	47.4623	0.56504	47.8532	0.5728	50.1466	0.6754	44.2345	0.5348
Median filtering	34.8623	0.00565	35.5175	0.0301	36.9109	0.03534	22.6301	0.0155
Salt and pepper noise	26.7163	0.12153	46.1605	0.7378	26.4035	0.1157	27.3673	0.1713
Cropping	3.84305	0.09536	3.4014	0.0762	3.3462	0.0764	3.6300	0.100
Compression	43.4441	0.21957	44.0487	0.1998	46.1554	0.2317	41.5755	0.2856
Rotation	21.8898	−0.0158	20.0117	−0.0046	19.6339	−0.0011	17.9435	0.0269
Resizing	49.4074	0.88312	47.210	0.8365	46.8850	0.8116	43.4394	0.8355
Sharpening	32.2288	0.46943	32.0762	0.4280	33.1590	0.4798	27.4106	0.4340
Gaussian filter	47.9443	0.81130	46.1605	0.7378	45.3153	0.7336	42.0658	0.7408