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arXiv · 1210.3098

Near-optimal compressed sensing guarantees for total variation minimization

Deanna Needell·Rachel Ward
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Abstract

Consider the problem of reconstructing a multidimensional signal from an underdetermined set of measurements, as in the setting of compressed sensing. Without any additional assumptions, this problem is ill-posed. However, for signals such as natural images or movies, the minimal total variation estimate consistent with the measurements often produces a good approximation to the underlying signal, even if the number of measurements is far smaller than the ambient dimensionality. This paper extends recent reconstruction guarantees for two-dimensional images to signals of arbitrary dimension d>1 and to isotropic total variation problems. To be precise, we show that a multidimensional signal x can be reconstructed from O(sd*log(N^d)) linear measurements using total variation minimization to within a factor of the best s-term approximation of its gradient. The reconstruction guarantees we provide are necessarily optimal up to polynomial factors in the spatial dimension d.

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Deanna Needell, Rachel Ward. 2012-10-11. Near-optimal compressed sensing guarantees for total variation minimization. https://doi.org/10.1109/tip.2013.2264681

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