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arXiv · 1702.02485

Biologically-inspired characterization of sparseness in natural images

Laurent U Perrinet
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Abstract

Natural images follow statistics inherited by the structure of our physical (visual) environment. In particular, a prominent facet of this structure is that images can be described by a relatively sparse number of features. We designed a sparse coding algorithm biologically-inspired by the architecture of the primary visual cortex. We show here that coefficients of this representation exhibit a heavy-tailed distribution. For each image, the parameters of this distribution characterize sparseness and vary from image to image. To investigate the role of this sparseness, we designed a new class of random textured stimuli with a controlled sparseness value inspired by our measurements on natural images. Then, we provide with a method to synthesize random textures images with a given statistics for sparseness that matches that of some given class of natural images and provide perspectives for their use in neurophysiology.

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Laurent U Perrinet. 2017-02-08. Biologically-inspired characterization of sparseness in natural images. https://doi.org/10.1109/euvip.2016.7764592

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