Continuous Sign Language Recognition using Multimodal Input and Handshape-aware Boundary Detection
Paper · 2026 · Mingyu Zhao, Zhanfu Yang, Yang Zhou et al.
Summary
Recognizing signs in continuous American Sign Language (ASL) is harder than classifying isolated clips. Each sign's start and end frames must be found, and signs in running discourse differ from their dictionary (citation) forms. The authors use a two-step pipeline: they first split a sentence video into signs, then classify each segment. Segmentation is framed as frame-level BIO tagging over 3D skeletal features. A spatio-temporal convolutional network processes these features, with added velocity and acceleration cues. Certain handshapes tend to appear where signs begin and end. To exploit this, the authors pretrain a classifier for 87 linguistically defined handshape categories on a dataset merged and normalized from several existing sources. Its features are fed into the segmentation stream through gated cross-attention. The recognizer is trained on both citation-form signs and signs cut from continuous signing using manual annotations. On the ASLLRP corpus, the system reportedly outperforms earlier approaches by a clear margin. This matters because reliable boundary detection is a prerequisite for practical CSLR applications such as captioning or interpretation support.
Key points
- Segmentation uses B/I/O labels per frame rather than plain IO tagging. This lets the model separate signs that directly follow each other with no "outside" frames between them.
- The handshape classifier covers 87 canonical handshape categories. It is pretrained on a newly unified dataset built from several existing collections, then fused with the segmentation model through cross-attention with a gating mechanism.
- Evaluation is done on ASLLRP data, with gloss labels kept consistent across all datasets used. Recognition is applied only to signs with at least 6 training examples, so the system is not yet fully end-to-end.
- The scope is limited to right-handed signers and signs involving the dominant hand. Fingerspelling, classifiers and gestures are not handled separately.
- The available text claims significant gains over previous work, but the excerpt omits the exact scores.
Institutions
Fields, topics and concepts
📚 Shelves 5The field of science this work belongs to (OpenAlex fields).Computer Science · 18,614 worksComputer Vision and Pattern Recognition · 3,486 worksPsychology · 1,649 worksDevelopmental and Educational Psychology · 523 worksHuman-Computer Interaction · 160 works
🧭 Topics 1Research subjects and languages the work is about.Vision & language · 811 works
Cite
Cite as Mingyu Zhao, Zhanfu Yang, Yang Zhou, Zhaoyang Xia, Can Jin, Xiaoxiao He, Shuhang Lin, Carol Neidle and Dimitri Metaxas. 2026. Continuous Sign Language Recognition using Multimodal Input and Handshape-aware Boundary Detection. Proceedings of the LREC 2026 12th Workshop on the Representation and Processing of Sign Languages: Language in Motion.
@inproceedings{zhao2026continuous,
title = {{Continuous Sign Language Recognition using Multimodal Input and Handshape-aware Boundary Detection}},
author = {Mingyu Zhao, Zhanfu Yang, Yang Zhou, Zhaoyang Xia, Can Jin, Xiaoxiao He, Shuhang Lin, Carol Neidle and Dimitri Metaxas},
booktitle = {Proceedings of the LREC 2026 12th Workshop on the Representation and Processing of Sign Languages: Language in Motion},
year = {2026},
doi = {10.63317/22bkv35eirvm},
url = {https://doi.org/10.63317/22bkv35eirvm}
}References
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