الفهرس 
Thesis OrganizationOnly 14 pages are availabe for public view
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Abstract
This thesis is mainly concerned with data embedding in color images through the communication process. The data to be embedded in the form of image or audio signals. The main objectives of this thesis is twofold. Securing the data to be embedded through encryption and increasing the payload to be embedded through the fusion process. Another objective is to keep the quality of the cover image so as not to reveal any signs about the watermarking. To achieve these objectives, three proposed schemes are presented in this thesis.
The first scheme comprises the embedding of three encrypted gray-scale images in the three color components of the cover image through utilization of Singular Value Decomposition (SVD), Multi-level Discrete Wavelet Transform (DWT) and Chaotic Baker Map. The second scheme adopts a gray-scale cover image in addition to a color image and three gray-scale images as watermarks. A fusion strategy is adopted in this scheme to maximize the embedding capacity. The performance of these two proposed schemes is measured using evaluation metrics such as Peak Signal to Noise Ratio (PSNR) and Correlation Coefficient (Cr). In the third proposed scheme, audio signals are embedded as watermarks in a color cover image based on SVD and both Arnold and Baker Maps. To measure the performance of the third proposed scheme Signal-to-Noise Ratio (SNR), Segmental Signal-to-Noise Ratio (SNRseg), Log-Likelihood Ratio (LLR), Spectral Distortion (SD), Unified Averaged Changed Intensity (UACI) and Number of Pixel `Changing Rate (NPCR) are used as evaluation metrics.
A comparative study is done with the most recent schemes. The results reveal that the proposed schemes enhance both the capacity and the security of embedded information without affecting the perceptual quality of the original objects. Indeed, the proposed schemes are more robust where they perfectly extract watermark in the presence of severe attacks such as Noise, Rotation, Blurring, Cropping and Histogram Equalization.