Papers › Sequencer: Deep LSTM for Image Classification

Sequencer: Deep LSTM for Image Classification

4 May 2022arXiv:2205.01972archive 2025-07-28

Yuki Tatsunami, Masato Taki

In recent computer vision research, the advent of the Vision Transformer (ViT) has rapidly revolutionized various architectural design efforts: ViT achieved state-of-the-art image classification performance using self-attention found in natural language processing, and MLP-Mixer achieved competitive performance using simple multi-layer perceptrons. In contrast, several studies have also suggested that carefully redesigned convolutional neural networks (CNNs) can achieve advanced performance comparable to ViT without resorting to these new ideas. Against this background, there is growing interest in what inductive bias is suitable for computer vision. Here we propose Sequencer, a novel and competitive architecture alternative to ViT that provides a new perspective on these issues. Unlike ViTs, Sequencer models long-range dependencies using LSTMs rather than self-attention layers. We also propose a two-dimensional version of Sequencer module, where an LSTM is decomposed into vertical and horizontal LSTMs to enhance performance. Despite its simplicity, several experiments demonstrate that Sequencer performs impressively well: Sequencer2D-L, with 54M parameters, realizes 84.6% top-1 accuracy on only ImageNet-1K. Not only that, we show that it has good transferability and the robust resolution adaptability on double resolution-band.

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okojoalg/sequencer officialmentioned in papermentioned on GitHubpytorch report
rwightman/pytorch-image-models officialmentioned in papermentioned on GitHubpytorch report
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Downsample2D okojoalg/sequencer/models/two_dim_sequencer.py official repository ran · metamorphic tier: invariant Apache-2.0 (permissive) · 71520c22fcd16235 · report
PatchEmbed okojoalg/sequencer/models/two_dim_sequencer.py official repository ran · metamorphic tier: invariant fingerprinted Apache-2.0 (permissive) · d21dc0c3ff2326b2 · report
RNN2DBase okojoalg/sequencer/models/two_dim_sequencer.py official repository ran Apache-2.0 (permissive) · b68d5c2770b76e3e · report
RNNIdentity okojoalg/sequencer/models/two_dim_sequencer.py official repository ran · metamorphic tier: deterministic fingerprinted Apache-2.0 (permissive) · cee0eb3911fd1719 · report
LSTM2D okojoalg/sequencer/models/two_dim_sequencer.py official repository unverified Apache-2.0 (permissive) · e5ad67deb204c7fb · report
Sequencer2D okojoalg/sequencer/models/two_dim_sequencer.py official repository unverified Apache-2.0 (permissive) · 07c6c53559ef34c9 · report
Sequencer2DBlock okojoalg/sequencer/models/two_dim_sequencer.py official repository unverified Apache-2.0 (permissive) · 21b70a992bd5f441 · report
_init_weights okojoalg/sequencer/models/two_dim_sequencer.py official repository unverified Apache-2.0 (permissive) · 58c0c12066377b33 · report
get_stage okojoalg/sequencer/models/two_dim_sequencer.py official repository unverified Apache-2.0 (permissive) · caa022d5744fcda0 · report

Tasks

Domain GeneralizationImage ClassificationInductive Biasimage-classification

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Domain Generalization ImageNet-A Sequencer2D-L Top-1 accuracy % 35.5 #25 of 39 Archive leaderboard report
Domain Generalization ImageNet-C Sequencer2D-L mean Corruption Error (mCE) 48.9 #25 of 47 Archive leaderboard report
Domain Generalization ImageNet-R Sequencer2D-L Top-1 Error Rate 51.9 #27 of 39 Archive leaderboard report
Domain Generalization ImageNet-Sketch Sequencer2D-L Top-1 accuracy 35.8 #20 of 20 Archive leaderboard report
Image Classification ImageNet Sequencer2D-L↑392 GFLOPs 50.7 #303 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-L↑392 Number of params 54M #303 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-L↑392 Top 1 Accuracy 84.6% #303 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-L GFLOPs 16.6 #432 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-L Number of params 54M #432 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-L Top 1 Accuracy 83.4% #432 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-M GFLOPs 11.1 #500 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-M Number of params 38M #500 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-M Top 1 Accuracy 82.8% #500 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-S GFLOPs 8.4 #552 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-S Number of params 28M #552 of 1060 Archive leaderboard report
Image Classification ImageNet Sequencer2D-S Top 1 Accuracy 82.3% #552 of 1060 Archive leaderboard report
Image Classification ImageNet ReaL Sequencer2D-L Accuracy 87.9 #29 of 57 Archive leaderboard report
Image Classification ImageNet V2 Sequencer2D-L Top 1 Accuracy 73.4 #21 of 33 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

AdamWAverage PoolingBiLSTMDense ConnectionsDropoutGlobal Average PoolingLSTMLayer NormalizationMLP-MixerResidual ConnectionSigmoid ActivationTanh ActivationVision Transformer

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