الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
The amount of data is exploding due to the development of various
technologies such as cloud, artificial intelligence, and big data. Along with
the rapid development of wireless network technology such as mobile
communication and multimedia display device technology, a lot of
multimedia information is transmitted and shared through the Internet.
Therefore, it is very important to protect images from problems such as
illegal copying and illegal distribution.
There has been an enormous increase in the distribution and archiving
of Digital Imaging and Communications in Medicine (DICOM) medical
images in recent years. With the widespread adoption of digital formats for
medical records and the growing utilization of telemedicine services, large
volumes of radiological and clinical imaging data are now routinely
transmitted electronically and retained digitally. This reflects the vast gains
in connectivity of healthcare networks and transition from traditional filmbased to computational medical imaging modalities across the industry.
Secure exchange and long-term preservation of such sensitive patient
information embodied in DICOMs has become mission critical as a result of
the massive escalation in the digital dissemination and remote access to these
important medical files.
There are generally three main approaches to secure digital images -
steganography, watermarking, and encryption. Steganography involves
hiding information within other media, while watermarking embeds
identifying signatures directly into image content. Encryption, on the other
hand, is considered the most direct and efficient method. It ensures medical
image security by converting the original, or plaintext, image into an
unreadable form (cipher image) using a secret encryption key. In this thesis two proposed cryptosystems are designed and evaluated
using security evaluation parameters. The first proposed cryptosystem is
mainly based on a proposed technique called layered cellular automata
(LCA), which enhance the security parameters for medical images either
coloured or grey ones, the simulation results showed that the proposed
system has the smallest processing time compared with other related
schemes. Thus this cryptosystem can be adopted for real time applications.
The second proposed cryptosystem based on non-uniform cellular
automata technique in conjunction with DNA and JSMP map, the simulation
results showed that, this encryption technique is an efficient technique,
compared with other related techniques. For the two proposed techniques
security parameters used to evaluate them are visual subjective analysis,
entropy analysis, correlation analysis, differential attack analysis, histogram
analysis, cropping attack analysis, and noise analysis.
Finally, MIMO-OFDM wireless system was designed as a
communication system for evaluating transmission of encrypted image
through it. In the beginning, performance evaluation of four known chaotic
based encryption techniques were adopted and compared when transmitting
over MIMO-OFDM system. Then, the two proposed encryption schemes are
evaluated under MIMO-OFDM wireless communication system.