Papers › Sparse Spatial Transformers for Few-Shot Learning

Sparse Spatial Transformers for Few-Shot Learning

27 Sep 2021arXiv:2109.12932archive 2025-07-28

Haoxing Chen, Huaxiong Li, Yaohui Li, Chunlin Chen

Learning from limited data is challenging because data scarcity leads to a poor generalization of the trained model. A classical global pooled representation will probably lose useful local information. Many few-shot learning methods have recently addressed this challenge using deep descriptors and learning a pixel-level metric. However, using deep descriptors as feature representations may lose image contextual information. Moreover, most of these methods independently address each class in the support set, which cannot sufficiently use discriminative information and task-specific embeddings. In this paper, we propose a novel transformer-based neural network architecture called sparse spatial transformers (SSFormers), which finds task-relevant features and suppresses task-irrelevant features. Particularly, we first divide each input image into several image patches of different sizes to obtain dense local features. These features retain contextual information while expressing local information. Then, a sparse spatial transformer layer is proposed to find spatial correspondence between the query image and the full support set to select task-relevant image patches and suppress task-irrelevant image patches. Finally, we propose using an image patch-matching module to calculate the distance between dense local representations, thus determining which category the query image belongs to in the support set. Extensive experiments on popular few-shot learning benchmarks demonstrate the superiority of our method over state-of-the-art methods. Our source code is available at \url{https://github.com/chenhaoxing/ssformers}.

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batched_index_select chenhaoxing/ssformers/modules/utils.py official repository unverified MIT (permissive) · c0aedf9b31c98a1e · report
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Tasks

Few-Shot Image ClassificationFew-Shot LearningPatch Matching

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Few-Shot Image Classification CIFAR-FS 5-way (1-shot) SSFormers Accuracy 74.5 #29 of 38 Archive leaderboard report
Few-Shot Image Classification CIFAR-FS 5-way (5-shot) SSFormers Accuracy 86.61 #27 of 39 Archive leaderboard report
Few-Shot Image Classification FC100 5-way (1-shot) SSFormers Accuracy 43.72 #17 of 22 Archive leaderboard report
Few-Shot Image Classification FC100 5-way (5-shot) SSFormers Accuracy 58.92 #17 of 22 Archive leaderboard report
Few-Shot Image Classification Mini-Imagenet 5-way (1-shot) SSFormers Accuracy 67.25 #47 of 105 Archive leaderboard report
Few-Shot Image Classification Mini-Imagenet 5-way (5-shot) SSFormers Accuracy 82.75 #38 of 95 Archive leaderboard report
Few-Shot Image Classification Tiered ImageNet 5-way (1-shot) SSFormers Accuracy 72.52 #25 of 49 Archive leaderboard report
Few-Shot Image Classification Tiered ImageNet 5-way (5-shot) SSFormers Accuracy 86.61 #25 of 51 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

Absolute Position EncodingsAdamAttentionBPEDense ConnectionsDropoutLabel SmoothingLayer NormalizationLinear LayerMulti-Head AttentionPosition-Wise Feed-Forward LayerResidual ConnectionSoftmaxSpatial TransformerTransformer

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