Image Encryption with Double Spiral Scans and Chaotic Maps

Table 2

Correlation coefficients of the original images and their encrypted images.

Test image	Horizontal direction		Vertical direction		Diagonal direction
	Original image	Encrypted image	Original image	Encrypted image	Original image	Encrypted image
Lena	0.9757	−0.0685	0.9692	0.0857	0.8820	0.0059
Fingerprint	0.9142	0.0933	0.9738	0.0616	0.8050	−0.0101
Woman	0.9655	0.0334	0.9758	0.1030	0.8825	−0.0007
Lake	0.9677	−0.0062	0.9638	−0.0137	0.9144	−0.0214
Goldhill	0.9780	−0.0351	0.9625	0.0556	0.6915	0.0330
ChestXray	0.9974	0.1183	0.9969	−0.0403	0.9364	−0.0059