1,421 research outputs found

    Secure and Robust Image Watermarking Scheme Using Homomorphic Transform, SVD and Arnold Transform in RDWT Domain

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    The main objective for a watermarking technique is to attain imperceptibility, robustness and security against various malicious attacks applied by illicit users. To fulfil these basic requirements for a scheme is a big issue of concern. So, in this paper, a new image watermarking method is proposed which utilizes properties of homomorphic transform, Redundant Discrete Wavelet Transform (RDWT), Arnold Transform (AT) along with Singular Value Decomposition (SVD) to attain these required properties. RDWT is performed on host image to achieve LL subband. This LL subband image is further decomposed into illumination and reflectance components by homomorphic transform. In order to strengthen security of proposed scheme, AT is used to scramble watermark. This scrambled watermark is embedded with Singular Values (SVs) of reflectance component which are obtained by applying SVD to it. Since reflectance component contains important features of image, therefore, embedding of watermark in this part provides excellent imperceptibility. Proposed scheme is comprehensively examined against different attacks like scaling, shearing etc. for its robustness. Comparative study with other prevailing algorithms clearly reveals superiority of proposed scheme in terms of robustness and imperceptibility

    A New Digital Video Watermarking Using Decimated Wavelet and Principle Component Analysis in YCbCr Domain

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    Digital watermarking is a technology used for security and for the copyright protection of digital media application. In this letter, we introduced “A New Digital Video Watermarking Using Decimated Wavelet and Principle Component Analysis in YCbCr domain”. First, the input video stream will be divided into number of frames and then select one frame to embed the information into it. Now convert it into YCbCr color space and apply DWT followed by PCA to get the watermarked frame then replace this frame with the original frame to obtain the watermarked video. It has also tested for various attacks such asRST, cropping, compression, filtering and Gaussian noise successfully with reduced bit error. Peak signal to noise ratio (PSNR) and structural similarity index (SSIM) used to measure the quality of watermarked frame. Simulated results had shown that the proposed algorithm gives more superior results and higher imperceptibility over existing algorithm in terms of quality metrics

    Mathematical transforms and image compression: A review

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    It is well known that images, often used in a variety of computer and other scientific and engineering applications, are difficult to store and transmit due to their sizes. One possible solution to overcome this problem is to use an efficient digital image compression technique where an image is viewed as a matrix and then the operations are performed on the matrix. All the contemporary digital image compression systems use various mathematical transforms for compression. The compression performance is closely related to the performance by these mathematical transforms in terms of energy compaction and spatial frequency isolation by exploiting inter-pixel redundancies present in the image data. Through this paper, a comprehensive literature survey has been carried out and the pros and cons of various transform-based image compression models have also been discussed

    Automatic extraction and tracking of face sequences in MPEG video

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    Ph.DDOCTOR OF PHILOSOPH
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