International Journal of Applied Engineering Research ISSN 0973-4562 Volume 12, Number 23 (2017) pp. 13265-13280
© Research India Publications. http://www.ripublication.com
13265
A Survey and Analysis of the Image Encryption Methods
Omar Farook Mohammad
1
, Mohd Shafry Mohd Rahim
1,2
, Subhi Rafeeq Mohammed Zeebaree
3
and Falah Y.H. Ahmed
4
,
1
Faculty of Computing, Universiti Teknologi Malaysia (UTM), Johor, Malaysia.
2
IRDA Digital Media Center, Universiti Teknologi Malaysia (UTM), Johor, Malaysia.
3
Computer and Communications Engineering Department, College of Engineering, Nawroz University, Duhok, Iraq.
4
Faculty of Information Sciences & Engineering, Management and Science University (MSU), 40100 Shah Alam, Selangor, Malaysia.
1
Orcid: 0000-0001-7347-5283
Abstract
At the present time, the protection of multimedia data has
become a very important process which can be achieved by
encryption. Basically, so many different techniques have been
used to protect private image data from those who illegally try
to have access. An efficient cryptographic scheme is one that
has a space of a large key that resists brute force search time,
less execution time complexity/ Highspeed and should be able
to provide high confusion and diffusion for good security. In
this paper, we survey an existing work which uses classic and
modern techniques for image encryption, as the classic
techniques used for text based on alphabets as basic elements
while the modern techniques overcome this limitation by used
mathematical algorithms for coding the information due to their
digital system. A comparison has been conducted between
several ciphers techniques (classic and modern) for images
based on various parameters such as: Histogram, Correlation,
Number of Pixels Change Rate (NPCR), Unified Average
Changing Intensity (UACI), Peak Signal to Noise Ratio
(PSNR), Entropy and Time complexity. An analysis of
simulation result shows that chaotic encryption technique
especially hyper-chaotic is the most efficient among the all.
Keywords: Classical and Modern cryptography, Chaotic,
Correlation, Histogram, Key Sensitivity, Entropy.
INTRODUCTION
Recently, additional security and privacy problems have been
emerged from the rapid development that occurred in the
communication networks field. The need to secure and reliable
means of communication containing images and videos have
become extremely necessary, not to mention other related
issues that should be taken into consideration. Accordingly,
network security and data encryption issues are considered as a
significant subject. Currently, images are considered as the
most important source of information. The applications of
image and video encryption can be used in various fields like
wireless communication, multimedia systems, medical
imaging, telemedicine, and military communication [1].
Being a good source to provide users with security and privacy
needed, the digital imaging can play a significant role in
multimedia technology field. Image encryption is a significant
process to deny any unauthorized user access [2,3]. Sometime
encryption used to increase the ambiguity of the data inside the
image when it used with steganography at the same time and
watermarking as well [4,5]. In addition to images many
algorithms applied on text for recognize scripts which is done
by the segmentation where is play a vital role in script
recognition process, as well as some algorithms employed on
voice with multi-speaker by vocal tract length normalization to
automatic speech recognition [6,7].
The two terms cryptography and cryptanalysis need to be
clearly defined to give wide comprehension for the work in
progress. Cryptography mathematically encrypts and decrypts
information so that the user becomes capable of storing and
transmitting information that is sensitive within insecure
networks. This information is viable to the public except the
specified recipients. As for cryptanalysis, it be defined as a
process to analyze and break down secure communication.
Encryption is a process in which an algorithm is used to make
the transformed information is un-readable by unauthorized
users. Therefore, cryptographic method is simply based on
encoding and transforming information into unreadable cipher
text to protect a sensitive data such as credit card number. The
encoded data may only be decrypted or turned readable by a
key. Both of symmetric-key and asymmetric-key encryptions
are considered as primary types of encryption [8]. Many
evaluation methods used in this regard such as histogram,
chaotic which is most popular issue to generate key in
encryption and other methods such as simulation [9-11].
Decryption is a reverse process in which unreadable
transformed data that has been subjected to encryption is turned
back to unencrypted form. In a decryption process, the system
extracts and converts the garbled data and then transform it into
texts and images that are easily to be understood by both reader
and system. Generally, decryption process can be accomplished
either manually, automatically or by using set of keys or
passwords [12]. Image encryption techniques give challenging
due to used widely in many fields such as pattern recognition,
face detection, image restoration and matching, etc. [13].