A mixture distribution model is introduced to characterize the source statistics in a frequency domain image coder. More speciically, a Gaussian mixture distribution is shown to be a good statistical model of the probability density function of the composite decomposed signal. Theoretical results based on the mixture distribution model are found that quantify the obtainable entropy rate gain in...

Context-based authentication methods enable the unobtrusive establishment of authentication or even secure keys. While several context-based authentication methods have been proposed recently, often the entropy of the seed for the cryptographic keys is not exploited. We study the entropy of audio fingerprints which can be utilized to pair devices in close proximity. In this work, for 600 audio ...

Starting from metric of general nonextreme stationary axisymmetric black hole in four-dimensional spacetime, both statistical-mechanical and thermo-dynamical entropies are studied. First, by means of the " brick wall " model in which the Dirichlet condition is replaced by a scattering ansatz for the field functions at the horizon and with the Pauli-Villars regularization scheme, an expression f...