Papers › The 2021 Image Similarity Dataset and Challenge

The 2021 Image Similarity Dataset and Challenge

17 Jun 2021arXiv:2106.09672archive 2025-07-28

Matthijs Douze, Giorgos Tolias, Ed Pizzi, Zoë Papakipos, Lowik Chanussot, Filip Radenovic, Tomas Jenicek, Maxim Maximov, Laura Leal-Taixé, Ismail Elezi, Ondřej Chum, Cristian Canton Ferrer

This paper introduces a new benchmark for large-scale image similarity detection. This benchmark is used for the Image Similarity Challenge at NeurIPS'21 (ISC2021). The goal is to determine whether a query image is a modified copy of any image in a reference corpus of size 1~million. The benchmark features a variety of image transformations such as automated transformations, hand-crafted image edits and machine-learning based manipulations. This mimics real-life cases appearing in social media, for example for integrity-related problems dealing with misinformation and objectionable content. The strength of the image manipulations, and therefore the difficulty of the benchmark, is calibrated according to the performance of a set of baseline approaches. Both the query and reference set contain a majority of "distractor" images that do not match, which corresponds to a real-life needle-in-haystack setting, and the evaluation metric reflects that. We expect the DISC21 benchmark to promote image copy detection as an important and challenging computer vision task and refresh the state of the art. Code and data are available at https://github.com/facebookresearch/isc2021

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Tasks

Copy DetectionImage Similarity DetectionMisinformation

Datasets

Introduced by this paper, per the archive.

DISC21

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Similarity Detection DISC21 dev HOW+ASMK Time (ms) 150 #1 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev HOW+ASMK hardware Tesla P-100 #1 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev HOW+ASMK w/o normalization 17.32 #1 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev HOW+ASMK with normalization 37.15 #1 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev Multigrain 1500 dim Time (ms) 23 #2 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev Multigrain 1500 dim dimension 1500 #2 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev Multigrain 1500 dim hardware Tesla V100 #2 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev Multigrain 1500 dim w/o normalization 16.47 #2 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev Multigrain 1500 dim with normalization 36.42 #2 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST PCA 256 dimension 256 #3 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST PCA 256 hardware CPU, 2.2 GHz, 40 threads #3 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST PCA 256 w/o normalization 15.56 #3 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST 960 dim Time (ms) 0.55 #4 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST 960 dim dimension 960 #4 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST 960 dim hardware CPU, 2.2 GHz, 40 threads #4 of 4 Archive leaderboard report
Image Similarity Detection DISC21 dev GIST 960 dim w/o normalization 14.42 #4 of 4 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.

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