On SIFTs and their scales

@article{Hassner2012OnSA,
  title={On SIFTs and their scales},
  author={Tal Hassner and Viki Mayzels and Lihi Zelnik-Manor},
  journal={2012 IEEE Conference on Computer Vision and Pattern Recognition},
  year={2012},
  pages={1522-1528}
}
Scale invariant feature detectors often find stable scales in only a few image pixels. Consequently, methods for feature matching typically choose one of two extreme options: matching a sparse set of scale invariant features, or dense matching using arbitrary scales. In this paper we turn our attention to the overwhelming majority of pixels, those where stable scales are not found by standard techniques. We ask, is scale-selection necessary for these pixels, when dense, scale-invariant matching… 

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