الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
With the advancements of multimedia communication, it has become apparent
that there is a bad need to perform image communication with confidence guarantee.
The problem with images is more serious as digital images are attacked through
transmission via the Internet or other communication media. To guarantee
trustworthiness and security for image transmission, image authentication techniques
have been proposed. By the image transmission with confidence guarantee, we need
to have a guarantee of image integrity at the receiver. Towards this objective, a
proposed framework is presented in this thesis. This framework comprises selfsignature
embedding in the transmitted images. The signatures are extracted from
image blocks in the Discrete Cosine Transform (DCT) domain and embedded in other
blocks in the same domain with certain weight to avoid deteriorating the resulting
image quality. A verification process is performed at the receiver to check content
modification or not. In addition, image watermarking is also used in the thesis with
DCT and Discrete Wavelet Transform (DWT) algorithm for authentication or
verification. In environments that are insecure, it is possible for an eavesdropper to
tamper images during transmission, and thus a multi-level security system consisting
of the DCT-based signature scheme with watermarking schemes based on DCT once
and DWT once has been proposed. Moreover, Double Random Phase Encoding
(DRPE) algorithm is used to secure the content of transmitted images. Finally, to
enhance the security level of transmitted images with better immunity to noise, a
hybrid scheme based on DCT-based signature and DRPE schemes has been proposed.