Abstract: In this paper, we present a technique of secure watermarking of grayscale and color images. This technique consists in applying the Singular Value Decomposition (SVD) in LWT (Lifting Wavelet Transform) domain in order to insert the watermark image (grayscale) in the host image (grayscale or color image). It also uses signature in the embedding and extraction steps. The technique is applied on a number of grayscale and color images. The performance of this technique is proved by the PSNR (Pick Signal to Noise Ratio), the MSE (Mean Square Error) and the SSIM (structural similarity) computations.
Abstract: Image or document encryption is needed through egovernment
data base. Really in this paper we introduce two matrices
images, one is the public, and the second is the secret (original). The
analyses of each matrix is achieved using the transformation of
singular values decomposition. So each matrix is transformed or
analyzed to three matrices say row orthogonal basis, column
orthogonal basis, and spectral diagonal basis. Product of the two row
basis is calculated. Similarly the product of the two column basis is
achieved. Finally we transform or save the files of public, row
product and column product. In decryption stage, the original image
is deduced by mutual method of the three public files.
Abstract: This paper deals with modeling and parameter
identification of nonlinear systems described by Hammerstein model
having Piecewise nonlinear characteristics such as Dead-zone
nonlinearity characteristic. The simultaneous use of both an easy
decomposition technique and the triangular basis functions leads to a
particular form of Hammerstein model. The approximation by using
Triangular basis functions for the description of the static nonlinear
block conducts to a linear regressor model, so that least squares
techniques can be used for the parameter estimation. Singular Values
Decomposition (SVD) technique has been applied to separate the
coupled parameters. The proposed approach has been efficiently
tested on academic examples of simulation.