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Spectral Remapping for Image Downscaling
Eduardo S. L. Gastal
and Manuel M. Oliveira

Instituto de Informática, UFRGS


ACM Transactions on Graphics.
Volume 36 (2017), Number 4, Proceedings of SIGGRAPH 2017, Article 145.


Abstract Downloads Results Video Reference Acknowledgements


We present an image downscaling technique capable of appropriately representing high-frequency structured patterns. Our method breaks conventional wisdom in sampling theory—instead of discarding high-frequency information to avoid aliasing, it controls aliasing by remapping such information to the representable range of the downsampled spectrum. The resulting images provide more faithful representations of their original counterparts, retaining visually-important details that would otherwise be lost. Our technique can be used with any resampling method and works for both natural and synthetic images. We demonstrate its effectiveness on a large number of images downscaled in combination with various resampling strategies. By providing an alternative solution for a long-standing problem, our method opens up new possibilities for image processing.



Full paper (24 MB, 16 pages)

ACM Copyright Notice: © Copyright held by the owner/authors. This is the author's version of the work. It is posted here for your personal use. Not for redistribution. The definitive version was published in ACM TOG, Vol. 36, 4, July 2017 —

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Video (in portuguese)



Eduardo S. L. Gastal and Manuel M. Oliveira. "Spectral Remapping for Image Downscaling". ACM Transactions on Graphics. Volume 36 (2017), Number 4, Proceedings of SIGGRAPH 2017, Article 145.


  author    = {Eduardo S. L. Gastal and Manuel M. Oliveira},
  title     = {Spectral Remapping for Image Downscaling},
  journal   = {ACM TOG},
  volume    = {36},
  number    = {4},
  year      = {2017},
  pages     = {145:1--145:16},
  articleno = {145},
  note      = {Proceedings of SIGGRAPH 2017}


Spectral Remapping, Image Downscaling, Frequency Remapping, Antialiasing, Resampling, Signal Processing, Gabor Transform, Fourier Transform.


CNPq-Brazil fellowships and grants # 306196/2014-0, 403591/2014-7, and 150550/2015-4.

Last updated: July 2019.