Nonlinear Multi-Image Encryption Scheme with the Reality-Preserving Discrete Fractional Angular Transform and DNA Sequences

Table 10

Correlation coefficients of adjacent pixels.

	Image	HD	VD	DD
	Peppers	0.9470	0.9489	0.9045
	House	0.9647	0.9768	0.9457
	Elaine	0.9564	0.9541	0.9389
	Bridge	0.9036	0.9286	0.8776
Proposed scheme	Encrypted image	−0.0043	−0.0011	0.0052
Ref. [48]	Encrypted image	0.0187	0.0495	−0.0246
Ref. [49]	Encrypted image	−0.0142	−0.0092	0.0157
	Baboon	0.7079	0.8365	0.6947
	Lax	0.7250	0.5911	0.5719
	Woman	0.9217	0.8801	0.8507
	Barbara	0.9070	0.8567	0.8100
Proposed scheme	Encrypted image	−0.0024	−0.0034	−0.0070
Ref. [48]	Encrypted image	−0.2044	0.0392	−0.0143
Ref. [49]	Encrypted image	−0.0011	−0.0039	−0.0136
	Couple	0.9421	0.9106	0.8758
	Airfield	0.9360	0.9249	0.9008
	Flowers	0.9826	0.9697	0.9580
	Lake	0.9330	0.9370	0.9046
Proposed scheme	Encrypted image	−0.0023	0.0015	−0.0063
Ref. [48]	Encrypted image	−0.0132	0.0142	0.0110
Ref. [49]	Encrypted image	0.0114	0.0126	−0.0021