On the Cryptanalysis of a Bit-Level Image Chaotic Encryption Algorithm

Table 3

Correlation coefficient of some encrypted images in the R channel.

Image	Original image			Encrypted image
	Vertical	Horizontal	Diagonal	Vertical	Horizontal	Diagonal
Lena	0.9239	0.9567	0.8888	−0.0024	0.0035	0.0014
Flower	0.9563	0.9542	0.9238	0.0025	−0.0017	−0.0037
Greens	0.9758	0.9789	0.9622	−0.0007	0.0103	0.0047
Koala	0.9078	0.9051	0.8687	0.0016	0.0021	0.0039
Back	0.9178	0.9086	0.8661	−0.0036	−0.0071	−0.0019
Leaf	0.8865	0.8577	0.7798	−0.0074	−0.0003	0.0007
Bird	0.9494	0.9426	0.9212	−0.0089	−0.0009	−0.0004
Cup	0.9526	0.9454	0.9092	0.0001	0.0009	−0.0017