Image Blocking Encryption Algorithm Based on Laser Chaos Synchronization

Figure 4

The histograms of gray images with different sizes: (a) 220 × 220; (e) 256 × 256; (i) 512 × 512; (m) 1024 × 1024; and (q) 220 × 565.

(a) Plain image

(b) Histogram of (a)

(c) Encrypted image

(d) Histogram of (c)

(e) Plain image

(f) Histogram of (e)

(g) Encrypted image

(h) Histogram of (g)

(i) Plain image

(j) Histogram of (i)

(k) Encrypted image

(l) Histogram of (k)

(m) Plain image

(n) Histogram of (m)

(o) Encrypted image

(p) Histogram of (o)

(q) Plain image

(r) Histogram of (q)

(s) Encrypted image

(t) Histogram of (s)