Papers › Classification is a Strong Baseline for Deep Metric Learning

Classification is a Strong Baseline for Deep Metric Learning

30 Nov 2018arXiv:1811.12649archive 2025-07-28

Andrew Zhai, Hao-Yu Wu

Deep metric learning aims to learn a function mapping image pixels to embedding feature vectors that model the similarity between images. Two major applications of metric learning are content-based image retrieval and face verification. For the retrieval tasks, the majority of current state-of-the-art (SOTA) approaches are triplet-based non-parametric training. For the face verification tasks, however, recent SOTA approaches have adopted classification-based parametric training. In this paper, we look into the effectiveness of classification based approaches on image retrieval datasets. We evaluate on several standard retrieval datasets such as CAR-196, CUB-200-2011, Stanford Online Product, and In-Shop datasets for image retrieval and clustering, and establish that our classification-based approach is competitive across different feature dimensions and base feature networks. We further provide insights into the performance effects of subsampling classes for scalable classification-based training, and the effects of binarization, enabling efficient storage and computation for practical applications.

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azgo14/classification_metric_learning officialmentioned in papermentioned on GitHubpytorchApache-2.0 report

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evaluate_float_binary_embedding_faiss azgo14/classification_metric_learning/evaluation/retrieval.py official repository unverified Apache-2.0 (permissive) · 9946c564d23d70ad · report
evaluate_recall_at_k azgo14/classification_metric_learning/evaluation/retrieval.py official repository unverified Apache-2.0 (permissive) · ae95303ae4e8d0ff · report
extract_feature azgo14/classification_metric_learning/metric_learning/extract_features.py official repository unverified Apache-2.0 (permissive) · a5d16b074b789eb9 · report
test_nmi azgo14/classification_metric_learning/evaluation/nmi.py official repository unverified Apache-2.0 (permissive) · 78d69a1bfc666621 · report
test_nmi_faiss azgo14/classification_metric_learning/evaluation/nmi.py official repository unverified Apache-2.0 (permissive) · ea2bfa65e1089264 · report

Tasks

BinarizationClassificationClusteringContent-Based Image RetrievalFace VerificationGeneral ClassificationImage RetrievalMetric LearningRetrieval

1 archive task tag without a task page not shown.

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Retrieval CARS196 NormSoftmax2048 (ResNet-50) R@1 89.3 #3 of 8 Archive leaderboard report
Image Retrieval CUB-200-2011 NormSoftmax2048 (ResNet-50) R@1 65.3 #7 of 8 Archive leaderboard report
Image Retrieval In-Shop NormSoftmax2048 (ResNet-50) R@1 89.4 #5 of 7 Archive leaderboard report
Image Retrieval SOP NormSoftmax2048 (ResNet-50) R@1 79.5 #9 of 14 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

1x1 ConvolutionAverage PoolingBatch NormalizationBottleneck Residual BlockConvolutionGlobal Average PoolingKaiming InitializationMax PoolingReLUResidual BlockResidual Connection

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