For instance, considering gray-scale pixel values (L = 8), ideal NPCR and UACI are 99.
For differential analysis of all-zero image, the NPCR and UACI can be computed based on formula (22), (23) and (24), which are calculated in Table 5.
More particularly, the information entropy, NPCR and UACI of our algorithm are fairly satisfactory compared to conventional schemes.
The results of the differential analysis Category NPCR UACI Expected value 99.
The UACI measure is used to identify the average intensity difference in pixels between two images.
UACI = 1/WxH [[SIGMA]i, j Io (i, j) - I enc (i, j)/255 x 100% (2)
The encryption algorithm is better when obtained UACI value is around 33% .
From Table 2, it is found that the UACI value obtained by the proposed method is acceptable and matches with those methods in [8, 10, 12, 28].
The metrics such as histogram, correlation, NPCR, UACI, entropy, noise attack test, key space, cryptanalytics, and execution time are determined and compared with the standard values.
5% and the UACI values are approximately close to 30%.