This paper introduces the concepts of “selfconsistency” and “universality” to evaluate high precision camera distortion models. Self-consistency is evaluated by the residual error when the distortion generated with a certain model is corrected by the best parameters for the same model (used in reverse way, which is common practice). Analogously, universality is measured by the residual error wh...

Introduction Acquisition of a set Diffusion Weighted Images (DWIs) allows Diffusion Tensors and Tensor-derived quantities such as Fractional Anisotropy (FA) and Trace (TR) to be computed and used to infer the underlying white matter structure in the brain. DWIs are usually acquired with an echo-planar imaging (EPI) pulse sequence that produces images degraded by B0 field inhomogeneity, eddy cur...

In computer aided celiac disease diagnosis, endoscopes with wide-angle lenses are deployed which induce significant lens distortions. This work investigates an approach to automatize the estimation of the lens distortion, without a previous camera calibration. Knowing the discriminative power of all sensible distortion configurations, the model parameters are estimated. As the achieved paramete...

Introduction A new image-based ghost correction technique is described for general interleaved EPI. It estimates the phase distortions causing the ghosts as a general function of (x,y), even in the presence of significant overlap of parent image and ghosts. If the phase distortion is assumed to be a function of x (frequency encode direction) only, the new technique is similar to a recently publ...

In this paper a novel linear transconductor topology is proposed, where class-AB behavior based on adaptive biasing exploited to improve the range. The circuit Winner-Take-All already used for OTAs, and optimized linearity, proposed features gain control input tunability. provides of 43 ?S while consuming 70 ?W. range (1% variation dc transconductance gain) 470 mVpp, about 4.5 times larger than...