A+: Adjusted Anchored Neighborhood Regression for Fast Super-Resolution

  • Radu TimofteEmail author
  • Vincent De Smet
  • Luc Van Gool
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9006)


We address the problem of image upscaling in the form of single image super-resolution based on a dictionary of low- and high-resolution exemplars. Two recently proposed methods, Anchored Neighborhood Regression (ANR) and Simple Functions (SF), provide state-of-the-art quality performance. Moreover, ANR is among the fastest known super-resolution methods. ANR learns sparse dictionaries and regressors anchored to the dictionary atoms. SF relies on clusters and corresponding learned functions. We propose A+, an improved variant of ANR, which combines the best qualities of ANR and SF. A+ builds on the features and anchored regressors from ANR but instead of learning the regressors on the dictionary it uses the full training material, similar to SF. We validate our method on standard images and compare with state-of-the-art methods. We obtain improved quality (i.e. 0.2–0.7 dB PSNR better than ANR) and excellent time complexity, rendering A+ the most efficient dictionary-based super-resolution method to date.


Training Sample Neighborhood Size Sparse Code Convolutional Neural Network Dictionary Size 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was partly supported by the ETH General Founding (OK) and the Flemish iMinds framework.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Radu Timofte
    • 1
    Email author
  • Vincent De Smet
    • 2
  • Luc Van Gool
    • 1
    • 2
  1. 1.CVL, D-ITETETH ZürichZürichSwitzerland
  2. 2.VISICS, ESAT/PSIKU LeuvenLeuvenBelgium

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