• Corpus ID: 226226620

Two-layer clustering-based sparsifying transform learning for low-dose CT reconstruction

  title={Two-layer clustering-based sparsifying transform learning for low-dose CT reconstruction},
  author={Xikai Yang and Yong Long and Saiprasad Ravishankar},
Achieving high-quality reconstructions from low-dose computed tomography (LDCT) measurements is of much importance in clinical settings. Model-based image reconstruction methods have been proven to be effective in removing artifacts in LDCT. In this work, we propose an approach to learn a rich two-layer clustering-based sparsifying transform model (MCST2), where image patches and their subsequent feature maps (filter residuals) are clustered into groups with different learned sparsifying… 

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