The security of the encryption and verification techniques with significant output images is examined by a known-plaintext attack. We introduce an iterative phase-retrieval algorithm based on multiple intensity measurements ...
An efficient algorithm for the accurate computation of the linear canonical transform with complex transform parameters and with complex output variable is presented. Sampling issues are discussed and the requirements for ...
The linear canonical transform provides a mathematical model of paraxial propagation though quadratic phase systems. We review the literature on numerical approximation of this transform, including discretization,
sampling, ...
The linear canonical transform (LCT) describes the effect of any quadratic phase system (QPS) on an input optical wave ﬁeld. Special cases of the LCT include the fractional Fourier transform (FRT), the Fourier transform ...
By use of matrix-based techniques it is shown how the space–bandwidth product (SBP) of a signal, as indicated by the location of the signal energy in the Wigner distribution function, can be tracked through any quadraticphase ...
We present an analytical model of the dynamics of spatial harmonics of holographic grating profiles, taking into consideration record mechanisms (polymerization and components diffusion), absorption, interference pattern ...
The Fourier plane encryption algorithm is subjected to a known-plaintext attack. The simulated annealing heuristic algorithm is used to estimate the key, using a known plaintext-ciphertext pair, which decrypts
the ciphertext ...
We describe holographic grating formation in Acrylamide-based photopolymer material using the NonLocal Diffusion Driven model & discuss radical suppression leading to an inhibition period before grating growth. Diffusion ...
We demonstrate an optical system that encodes two dimensional data as different polarization states. The encrypted image is recorded using a digital holographic setup and the decryption is done numerically.
The number of samples required for efficient numerical simulation of wave propagation can be determined by a combination of Wigner phase-space techniques, wave energy confinement arguments, and a theorem relating
energy ...
We discuss an optical system that encodes an input signal to a polarization state, using a spatial light modulator (SLM). Using two SLMs the optical system multiplexes two 2D signals in the polarization domain, and we ...
We perform a numerical analysis of the double random phase encryption–decryption technique to determine how, in the case of both amplitude and phase encoding, the two decryption keys (the image- and Fourier-plane keys) ...
The amplitude-encoding case of the double random phase encoding technique is examined by deﬁning a cost function as a metric to compare an attempted decryption against the corresponding original input image. For
the case ...
In the work an analytical model of transmission holographic grating formation by light beams with non-uniform phase-amplitude profiles is presented. The model takes into consideration influence of light absorption of a ...