Cartoon Image Encryption Algorithm by a Fractional-Order Memristive Hyperchaos

Table 1

Correlation coefficients of plain image and encrypted image.

Image			Horizontal (0°)	Vertical (90°)	Diagonal (135°)	Counterdiagonal (45°)	Information entropies
Color image (Snow White)	R	Plain image	0.956870	0.969474	0.928532	0.920907	7.403101
		Encrypted image	0.062626	0.058355	0.043477	0.044810	7.701237
	G	Plain image	0.944415	0.960116	0.911802	0.902076	6.975635
		Encrypted image	0.068252	0.082912	0.049494	0.067867	7.719597
	B	Plain image	0.918471	0.943933	0.849832	0.902076	7.395466
		Encrypted image	0.048840	0.046259	0.048311	0.051689	7.677057
Gray image (Mickey Mouse)	Plain image		0.962524	0.963978	0.935959	0.942013	4.079404
	Encrypted image		7.503378 × 10^−4	3.060559 × 10^−4	3.191240 × 10^−4	8.427805 × 10^−5	7.990418
Binary image	Plain image		0.943381	0.965594	0.923663	0.926494	0.661291
	Encrypted image		−4.794829 × 10^−6	1.172771 × 10^−4	−7.071503 × 10^−4	0.002179	7.988849