الفهرس 
Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
Optical encryption and compression techniques have had the main role in the field of optical information processing in the last decades. For image and video communication, security of the transmission and storage of images or video frames is important in several applications such as biometric image storage and communication, real-time video and image transmission, confidential video conferencing over optical fibers, military applications, police identification procedures, online banking systems, governmental services, identity cards, etc. Optical scrambling or encryption is an evolving trend that relates optical systems with image processing. Various variants of optical encryption have been presented in the literature and these variants have been used in different applications.
This thesis is concerned with the introduction of an efficient technique for digital image encryption and compression to achieve high security and good compression. The compression process is based on the energy compaction property of the Discrete Cosine Transform (DCT). Four images are multiplexed together based on the first quadrants of their DCTs. The objective is to perform simultaneous compression of these four images in order to generate a single image. The encryption is implemented with the Double Random Phase Encoding (DRPE) process. This process can be implemented optically with two lenses and two random phase masks. The suggested hierarchy in the thesis can be used to secure multiple biometric images for the same person in order to build a cancelable multi-biometric framework. Cancelable biometric systems are well-known as more secure biometric recognition systems. In addition, the same strategy can be used to compress multiple video frames together to be transmitted in a secure manner over the communication channel. With this strategy four video frames can be transmitted, simultaneously, and they can also be secured from hacking attempts.