**TempCLR: Reconstructing Hands via Time-Coherent Contrastive Learning**
Andrea Ziani1,♣, [Zicong Fan](https://zc-alexfan.github.io)1,2,♣, [Muhammed Kocabas](https://ps.is.tuebingen.mpg.de/person/mkocabas)1,2, [Sammy Christen](https://ait.ethz.ch/people/sammyc/)1, [Otmar Hilliges](https://ait.ethz.ch/people/hilliges/)1
1ETH Zürich, 2Max Planck Institute for Intelligent Systems, Tübingen,
♣ Equal contribution
*In Proceedings of the International Conference on 3D Vision (3DV), 2022, Prague, Czechia.*
Code
## Goal

## Key Insight
- Large amount of unlabelled monocular RGB video data in the wild
- Limited accurate 3D annotation (often in-the-lab and not diverse)
- Use contrastive learning to enforce similar hand poses to have similar embeddings.

## Video

## In-the-wild results (no 3D supervision from this dataset)
TempCLR:


Without TempCLR:


## In-the-lab results (no 3D supervision from this dataset)
TempCLR:


Without TempCLR:


## Abstract
We introduce TempCLR, a new time-coherent contrastive learning approach for the structured regression task of 3D hand reconstruction. Unlike previous time-contrastive methods for hand pose estimation, our framework considers temporal consistency in its augmentation scheme, and accounts for the differences of hand poses along the temporal direction. Our data-driven method leverages unlabelled videos and a standard CNN, without relying on synthetic data, pseudo-labels, or specialized architectures. Our approach improves the performance of fully-supervised hand reconstruction methods by 15.9% and 7.6% in PA-V2V on the HO-3D and FreiHAND datasets respectively, thus establishing new state-of-the-art performance. Finally, we demonstrate that our approach produces smoother hand reconstructions through time, and is more robust to heavy occlusions compared to the previous state-of-the-art which we show quantitatively and qualitatively.
## Citing Us
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text
@inProceedings{ziani2022tempclr,
title={TempCLR: Reconstructing Hands via Time-Coherent Contrastive Learning},
author={Ziani, Andrea and Fan, Zicong and Kocabas, Muhammed and Christen, Sammy and Hilliges, Otmar},
booktitle={International Conference on 3D Vision (3DV)},
year={2022}
}
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