A substituted imidazolate-based MOF (SIM-1) membrane has been crystallized in situ on a tubular asymmetric alumina support that can be exploited for gas separation through preferential adsorption.

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In this paper, we propose a novel digital video watermarking scheme based on multi resolution motion estimation and artificial neural network. A multi resolution motion estimation algorithm is adopted to preferentially allocate the watermark to coefficients containing motion. In addition, embedding and extraction of the watermark are based on the relationship between a wavelet coefficient and its neighbor's. A neural network is given to memorize the relationships between coefficients in a 3x3 block of the image. Experimental results show that embedding watermark where picture content is moving is less perceptible. Further, it shows that the proposed scheme is robust against common video processing attacks. INTRODUCTIONThe sudden increase in watermarking interest is most likely due to the increase in concern over copyright protection of content. With the rapid growth of the Internet and the multimedia systems in distributed environments, digital data owners can easy transfer their multimedia documents across the Internet. However, current technology does not protect their copyrights properly. This leads to wide interest of multimedia security and multimedia copyright protection and it has become a great concern to copyrights owners in recent years. In the early days, encryption and control access techniques were used to protect the ownership of media. Digital watermarking, the art of hiding information in a robust and invisible manner, has been investigated as a complementary technology [1]. There are some desirable characteristics of effective watermarking techniques, including imperceptibility, robustness, and security [2]. Imperceptibility is the degree of perceptual similarity between the original and watermarked signals. It is desirable to embed the watermark in a discreet, unobtrusive manner so that the watermark is imperceptible under casual observation. Robustness is the resilience of the watermark against manipulations such as lossy compression, linear and nonlinear filtering, scaling, and cropping (Stirmark [3], dewatermarking attack [4]).Security is the ability of the watermark to resist hostile attacks. Attacks are not limited to removal of the watermark, but include watermark estimation or forgery, collusion, and ambiguity attacks.Obviously, it is desirable to have an imperceptible, robust, and secure watermarking technique.Digital watermarking has recently been extended from still images to video. Many algorithms have already been proposed in the literature. It goes from the simple adaptation of watermarking algorithm initially designed for still images [5] to the definition of specific video watermarking scheme [6]. Open paths still remain in video watermarking. This technology is indeed in its infancy and is far from being as mature as for still images.In this paper, we propose a novel approach to neural network watermarking for uncompressed video in the wavelet domain. The watermark is embedded multiple times into the host data. Before actually embedding the watermark information, it take...