Cryptanalysis and Improvement of Chaos-Based Image Encryption Scheme with Circular Inter-Intra-Pixels Bit-Level Permutation

Table 5

Average correlation coefficients of different algorithms.

Direction	Algorithm
	Ref. [21]	Ref. [22]	Ref. [23]	Original	Improved
Horizontal	0.01236	0.01268	0.01320	0.01177	0.00398
Vertical	0.00704	0.01174	0.00778	0.00208	0.00143
Diagonal	0.00502	0.02350	0.01822	0.00322	0.00415