Papers › Space-Time Crop & Attend: Improving Cross-modal Video Representation Learning

Space-Time Crop & Attend: Improving Cross-modal Video Representation Learning

18 Mar 2021ICCV 2021 10arXiv:2103.10211archive 2025-07-28

Mandela Patrick, Yuki M. Asano, Bernie Huang, Ishan Misra, Florian Metze, Joao Henriques, Andrea Vedaldi

The quality of the image representations obtained from self-supervised learning depends strongly on the type of data augmentations used in the learning formulation. Recent papers have ported these methods from still images to videos and found that leveraging both audio and video signals yields strong gains; however, they did not find that spatial augmentations such as cropping, which are very important for still images, work as well for videos. In this paper, we improve these formulations in two ways unique to the spatio-temporal aspect of videos. First, for space, we show that spatial augmentations such as cropping do work well for videos too, but that previous implementations, due to the high processing and memory cost, could not do this at a scale sufficient for it to work well. To address this issue, we first introduce Feature Crop, a method to simulate such augmentations much more efficiently directly in feature space. Second, we show that as opposed to naive average pooling, the use of transformer-based attention improves performance significantly, and is well suited for processing feature crops. Combining both of our discoveries into a new method, Space-Time Crop & Attend (STiCA) we achieve state-of-the-art performance across multiple video-representation learning benchmarks. In particular, we achieve new state-of-the-art accuracies of 67.0% on HMDB-51 and 93.1% on UCF-101 when pre-training on Kinetics-400.

PaperPDFConference PDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2103.10211")

Code

Syntology Ran 12 of 23 code samples harvested from 1 repository linked to this paper; 11 have no recorded run. Of those that ran: 12 ran with no contract checked.

By repository: official repository: 23 samples from 1 repository, 12 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

facebookresearch/GDT officialmentioned in papermentioned on GitHubpytorch report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

23 samples harvested; 12 ran; 0 honoured the contract we drafted; 11 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

12ran
11unverified

Licence: 0 of the 23 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from facebookresearch/GDT. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

Base facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 9d7e4b24b5660ac5 · report
BasicBlock facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 249b5820589b96d3 · report
Bottleneck facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 346198401060aa08 · report
Conv2Plus1D facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 4ab7412ae6131e98 · report
FFN facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · ba5523a1a6748c82 · report
MLP facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 66c25c20b741db7d · report
MultiHeadAttention facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 025f425a305c99a1 · report
R2Plus1dStem facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · dfb98feede0d7132 · report
Transformer facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · a45dddd3d20ddb5b · report
TransformerPooling facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 784b7c6f51d0dc00 · report
TransposeSqueeze facebookresearch/GDT/model.py official repository ran fingerprinted Apache-2.0 (permissive) · bd97e7875c7f6d01 · report
VideoResNet facebookresearch/GDT/model.py official repository ran Apache-2.0 (permissive) · 1c92b909d0cdece1 · report
AudioBaseNetwork facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · 05373243575c5edd · report
ResNet facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · 6840fa8301c4edba · report
Stica_TransformerFMCrop facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · 85fbc7f944b570fc · report
VideoBaseNetwork facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · cf7d2feaca7a7e0e · report
_resnet facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · f8df10b38e4d9f0d · report
_video_resnet facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · 471f1e36d731e3a0 · report
get_audio_feature_extractor facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · cf0d617f6919c7db · report
get_video_feature_extractor facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · dfcc255237250347 · report
r2plus1d_18 facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · 9982977c79b6bef4 · report
r2plus1d_34 facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · dcfa82af3e6afc58 · report
resnet9 facebookresearch/GDT/model.py official repository unverified Apache-2.0 (permissive) · f78b8e83121feab2 · report

Tasks

Representation LearningSelf-Supervised Learning

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections