الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
Nowadays, the Internet becomes the most essential and important way to connect people in the world. The Internet helps people to communicate, exchange and share information in easy manner with low cost, and high quality. Nevertheless, with the wide spread of the Internet and rapid growth of technologies, several challenges face data hiding process. Transmitting confidential data between two channels suffer from hacking. Therefore, protecting confidentiality has become a very essential issue.
Recently, several methods are developed to protect important information. The main idea is based on embedding important information in multimedia carrier such as: text, image, audio, and video. The developed methods may be classified as steganography and watermarking. Steganography aims to embed huge amount of secret data in multimedia carrier while watermarking aims to hid small amount of secret data in multimedia carrier.
Although, the watermarking process is widely used to hide/embed critical data into a cover image, the watermarked image may be attacked/hacked and the embedded data may be extracted or damaged. This thesis first presents a literature survey of information hiding, classifies the proposed methods, and introduces a comparative study between the different methods. Then, it presents an efficient data hiding watermarking approach for color image by using Singular Value Decomposition (SVD), multi-level Discrete Wavelet Transform (DWT) and wavelet fusion. Finally, it presents an efficient two-level security approach to protect colored watermark image. The main idea of the proposed watermarking approach is to separate the color image into its basic components (three channels); red, green, and blue. Then, fuse every channel with a gray scale image and integrate the three fused images into one gray scale fused image. Finally, the fused image is burred into a cover gray scale image to procedure the watermarked image by using DWT and SVD. On the other hand, the proposed two-level security approach first embeds the color image into a gray scale image using multi-level Discrete Wavelet Transform (DWT), Singular Value Decomposition (SVD), and wavelet fusion. Then, it performs additional encryption process on the watermarked image. The encryption is done by using two-dimensional logistic chaotic map in a case and Advanced Encryption Standard (AES) in another case. The proposed approaches are evaluated by using several images and different hacks on the transmitted images. The experimental results show that the proposed approaches are efficient and tolerant to versatile attacks such as Gaussian, Blur, Wrap, and Cropping. In addition, the extracted watermark images are recognized even when the marked images suffered from attacks.