This letter presents pseudolikelihood equations for the estimation of the Potts Markov random field model parameter on higher order neighborhood systems. The derived equation for second-order systems is a significantly reduced version of a recent result found in the literature (from 67 to 22 terms). Also, with the proposed method, a completely original equation for Potts model parameter estimation in third-order systems was obtained. These equations allow the modeling of less restrictive contextual systems for a large number of applications in a computationally feasible way. Experiments with both simulated and real remote sensing images provided good results.

Recently, we are attending to a huge evolution on the development of high performance computing platforms. Among these platforms, the GPU (Graphics Processing Units) stimulated by game industries, constantly demanding more graphical processing power, evolved from a simple graphical card to a general purpose computation parallel data processing device. This article shows the CPU's viability to general purpose computation, developing a speech recognition application inside. Dynamic Time Warping (DTW) is applied on a voice password identification. Normally, DTW requires large amount of data and processing time, so that it is an efficient technique to simple vocabulary, when the voice commands set is small. Using NVIDIA GeForce 8800 GTX, with 128 processing unit cores, and a CUDA (Compute Unified Device Architecture) software platform development architecture, the DTW application was implemented, and tested its performance.