publications

2024

1. ACM TKDD

   

   Learnable Transform-Assisted Tensor Decomposition for Spatio-Irregular Multidimensional Data Recovery

   Hao Zhang, Ting-Zhu Huang, Xi-Le Zhao, Shu-Qin Zhang, Jin-Yu Xie, Tai-Xiang Jiang , and Michael K. Ng

   ACM Transactions on Knowledge Discovery from Data, 2024

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   Tensor decompositions have been successfully applied to multidimensional data recovery. However, classical tensor decompositions are not suitable for emerging spatio-irregular multidimensional data (i.e., spatio-irregular tensor), whose spatial domain is non-rectangular, e.g., spatial transcriptomics data from bioinformatics and semantic units from computer vision. By using preprocessing (e.g., zero-padding or element-wise 0-1 weighting), the spatio-irregular tensor can be converted to a spatio-regular tensor and then classical tensor decompositions can be applied, but this strategy inevitably introduces bias information, leading to artifacts. How to design a tensor-based method suitable for emerging spatio-irregular tensors is an imperative challenge. To address this challenge, we propose a learnable transform-assisted tensor singular value decomposition (LTA-TSVD) for spatio-irregular tensor recovery, which allows us to leverage the intrinsic structure behind the spatio-irregular tensor. Specifically, we design a learnable transform to project the original spatio-irregular tensor into its latent spatio-regular tensor, and then the latent low-rank structure is captured by classical TSVD on the resulting regular tensor. Empowered by LTA-TSVD, we develop spatio-irregular low-rank tensor completion (SIR-LRTC) and spatio-irregular tensor robust principal component analysis (SIR-TRPCA) models for the spatio-irregular tensor imputation and denoising respectively, and we design corresponding solving algorithms with theoretical convergence. Extensive experiments including the spatial transcriptomics data imputation and hyperspectral image denoising show SIR-LRTC and SIR-TRPCA are superior performance to competing approaches and benefit downstream applications.

   @article{LTA-TSVD,
     author = {Zhang, Hao and Huang, Ting-Zhu and Zhao, Xi-Le and Zhang, Shu-Qin and Xie, Jin-Yu and Jiang, Tai-Xiang and Ng, Michael K.},
     journal = {ACM Transactions on Knowledge Discovery from Data},
     title = {Learnable Transform-Assisted Tensor Decomposition for Spatio-Irregular Multidimensional Data Recovery},
     year = {2024},
     doi = {10.1145/3701235},
   }

2. IEEE IGARSS

   

   Bi-Level Tensor Decomposition for Hyperspectral Image Restoration

   Yun-Yang Liu, Xi-Le Zhao^†, Jin-Yu Xie, Zhi Xu, and Gemine Vivone

   In IEEE International Geoscience and Remote Sensing Symposium, 2024

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   This paper proposes a bi-level tensor decomposition (BLTD), properly exploiting the characterization advantages of tensor subspace representation (TSR) and tensor ring decomposition (TRD). More specifically, the first level is related to the decomposition of a third-order tensor into its TSR using the tensor-tensor product (t-product), and the second level performs TRD on the coefficient tensor obtained by TSR. Leveraging the proposed BLTD, we design a bi-level tensor nuclear norm (BLTNN)-based model for hyperspectral images (HSIs) denoising. To solve the model, we develop an efficient alternating direction method of multipliers (ADMM)-based algorithm. Experimental results demonstrate the superior performance of our method compared to existing methods.

   @inproceedings{BLTD,
     author = {Liu, Yun-Yang and Zhao, Xi-Le and Xie, Jin-Yu and Xu, Zhi and Vivone, Gemine},
     title = {Bi-Level Tensor Decomposition for Hyperspectral Image Restoration},
     year = {2024},
     doi = {10.1109/IGARSS53475.2024.10640494},
     booktitle = {IEEE International Geoscience and Remote Sensing Symposium},
   }

2023

1. IEEE GRSL

   

   H2TF for Hyperspectral Image Denoising: Where Hierarchical Nonlinear Transform Meets Hierarchical Matrix Factorization

   Jin-Yu Xie^*, Jia-Yi Li^*, Yi-Si Luo, Xi-Le Zhao^†, and Jian-Li Wang

   IEEE Geoscience and Remote Sensing Letters, 2023

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   Recently, tensor singular value decomposition(t-SVD) has emerged as a promising tool for hyperspectral image (HSI) processing. In the t-SVD, there are two key building blocks: 1) the low-rank enhanced transform and 2) the accompanying low-rank characterization of transformed frontal slices. Previous t-SVD methods mainly focus on the developments of 1), while neglecting the other important aspect, i.e., the exact characterization of transformed frontal slices. In this letter, we exploit the potentiality in both building blocks by leveraging the hierarchical nonlinear transform (HNT) and the hierarchical matrix factorization (HMF) to establish a new tensor factorization (termed as H2TF). Compared with shallow counter partners, e.g., low-rank matrix factorization (MF) or its convex surrogates, H2TF can better capture complex structures of transformed frontal slices due to its hierarchical modeling abilities. We then suggest the H2TF-based HSI denoising model and develop an alternating direction method of multipliers-based algorithm to address the resultant model. Extensive experiments validate the superiority of our method over state-of-the-art (SOTA) HSI denoising methods.

   @article{h2tf,
     author = {Xie, Jin-Yu and Li, Jia-Yi and Luo, Yi-Si and Zhao, Xi-Le and Wang, Jian-Li},
     journal = {IEEE Geoscience and Remote Sensing Letters},
     title = {{H2TF} for Hyperspectral Image Denoising: Where Hierarchical Nonlinear Transform Meets Hierarchical Matrix Factorization},
     year = {2023},
     volume = {20},
     doi = {10.1109/LGRS.2023.3294933},
   }