Table 8.

Contrast analysis of plain and cipher images at $a=2,b=0.5,c=0.5,x_{1,0}=0.11,x_{2,0}=0.12$, and $k=0.87$.

Image	Contrast
	Plain Image	Cipher Image
lena ($256\times 256$)	0.3563	10.6201
house ($256\times 256$)	0.1741	10.5431
barbara ($256\times 256$)	0.9463	10.6986