Image Encryption Algorithm Based on the H-Fractal and Dynamic Self-Invertible Matrix

Table 2

The information entropies of some original images and their cipher images.

Image	Entropy
	Original	k = 3	k = 37	k = 487	Reference [32]	Reference [33]
Lena	7.4532	7.9971	7.9974	7.9974	7.9971	7.9968
Cameraman	6.9046	7.9976	7.9971	7.9972	7.9971	7.9904
Peppers	7.5797	7.9973	7.9978	7.9969	7.9968	7.9961
Baboon	7.0092	7.9972	7.9973	7.9975	—	7.9971