Reconstruction of elongated structures using ridge functions and natural pixels

In this work, reconstruction of elongated structures from a finite number o f projections using ridge functions within the framework of parallel beam g eometry is considered. Discretized versions of ridge functions, or natural pixels are used to obtain reconstruction from sampled data. Inversion formu lae for both ray- and strip-based projection data are derived. Possibilitie s of detecting the direction of elongated structures from few projections a nd detecting the defects in regular textures are discussed.