arXiv AI

SignTrace: Describe a Sign, Find the Word

SignTrace is a system that tackles the reverse‑lookup problem in Chinese sign language by allowing users to describe a sign in natural language and retrieve the corresponding entry from a dictionary of 6,699 signs. It combines large‑language‑model–based dictionary enrichment, action extraction, seven‑channel retrieval, and candidate reranking, achieving a 94.0% Hit@1 and a mean reciprocal rank of 0.9540 on a benchmark of 500 queries. The system has been deployed for user trials, receives positive informal feedback, and processes median queries in 13.37 seconds.

arXiv Computation and Language
Sep 4

A Reverse Sign Language Dictionary: Open-Vocabulary Sign Recognition from Continuous Signing via Video Captioning and Description Retrieval

The paper introduces a reverse sign‑language dictionary that recognizes signs from continuous signing without relying on gloss labels. It does this by first captioning a sign‑level video clip into a free‑form procedural description using an open‑weight vision‑language model, then retrieving the closest entry from a multilingual sentence encoder’s vocabulary of target descriptions. Experiments on a Japanese Sign Language dialogue corpus show that fine‑tuning the captioner boosts seen‑class retrieval from 4.5 % to 49 % and improves unseen‑class retrieval from 11.5 % to 21 %, approaching the performance of a standard closed‑set classifier while enabling open‑vocabulary recognition.

By Santiago Poveda-Guti\'errez, Hideki Nakayama, Mayumi Bono
Hugging Face Trending Papers
Sep 3

A Reverse Sign Language Dictionary: Open-Vocabulary Sign Recognition from Continuous Signing via Video Captioning and Description Retrieval

The paper introduces a reverse sign language dictionary that recognizes signs from continuous signing without relying on gloss annotations. It does this by captioning sign-level video clips into free-form procedural descriptions using an open-weight vision‑language model, then retrieving the closest description from a multilingual sentence encoder’s vocabulary. Experiments on a Japanese Sign Language corpus show that fine‑tuning the captioner boosts seen‑class retrieval from 4.5% to 49% and improves unseen‑class retrieval from 11.5% to 21%, matching or surpassing traditional closed‑set classifiers where applicable.

arXiv Computer Vision
Sep 3

SignMatch: Matching Dictionary Signs to Continuous Sign Language Video

SignMatch introduces a prototype‑structured embedding space that learns to match dictionary sign videos with continuous sign language footage based solely on visual similarity of handshape and motion. By mapping isolated dictionary exemplars into this space, the method enables direct, embedding‑based sign matching and can generalise to unseen signs using only dictionary examples. Experiments on ASL‑Citizen, ChaLearn OSLWL, and BOBSL CSLR2 benchmarks show strong cross‑dataset, cross‑task, and cross‑language performance, outperforming prior approaches on American, British, and Spanish sign languages without benchmark‑specific supervision.

By Ryan Wong, Youngjoon Jang, Liliane Momeni, G\"ul Varol, Andrew Zisserman
arXiv AI
Sep 4

Beyond BLEU: A Case for Redefining Sign Language Translation Benchmarks

The paper argues that BLEU-4, the prevailing metric for sign language translation (SLT), may not accurately reflect sign language proficiency because SLT models can exploit spurious correlations and spoken-language priors. By evaluating six SLT models on Phoenix-2014T and CSL-Daily, the authors show that higher BLEU-4 scores do not necessarily indicate better spatio-temporal understanding. They propose a new open-weight LLM QA protocol inspired by language-learning assessment, which better preserves salient content, aligns more closely with human rankings, and reveals differences between gloss-free and gloss-supervised systems that BLEU-4 obscures.

By Oline Ranum, Edward Fish, Simon Hadfield, Richard Bowden
arXiv Computer Vision
Sep 4

SignSeek: Learning Transferable Representations for Sign Dictionary Retrieval

SignSeek is a new method for learning transferable sign representations that enables efficient retrieval of signs from dictionaries using only a query video. It employs contrastive learning with saliency‑guided articulator masking, aligning same‑gloss signs across signers while focusing on the single most critical articulator per sign. Trained on 266K samples from multiple sign languages, SignSeek achieves state‑of‑the‑art cross‑corpus retrieval performance and zero‑shot generalisation to unseen British Sign Language, also improving isolated sign recognition and subtitle alignment.

By Sobhan Asasi, Ozge Mercanoglu Sincan, Richard Bowden
arXiv Computer Vision
Aug 27

Recognising BSL Fingerspelling in Continuous Signing Sequences

The paper introduces FS23K, a large-scale British Sign Language fingerspelling dataset created through an iterative annotation framework. It also presents a recognition model that incorporates bi‑manual interactions and mouthing cues, achieving a halved character error rate compared to previous state‑of‑the‑art methods. These results underscore the dataset’s and model’s value for advancing sign language research and automated annotation pipelines.

By Alyssa Chan, Taein Kwon, Andrew Zisserman
arXiv Computation and Language
Sep 3

SignBind-LLM: Multi-Stage Modality Fusion for Sign Language Translation

SignBind-LLM introduces a modular framework for sign language translation that separates continuous signing, fingerspelling, and lipreading into dedicated expert streams. Each expert is pre‑trained independently on about two million pseudo‑gloss sequences, eliminating the need for manual gloss annotation. A lightweight transformer fuses the expert outputs, and a pre‑trained language model converts the fused pseudo‑glosses into fluent English, achieving state‑of‑the‑art performance on multiple benchmarks with lower training cost.

By Marshall Thomas, Edward Fish, Richard Bowden
arXiv Computation and Language
2d ago

Towards Automated Lexicography: Generating and Evaluating Definitions for Learner's Dictionaries

The paper tackles the problem of automatically generating dictionary definitions for learner’s dictionaries, focusing on simplicity and clarity. It introduces a new evaluation framework that uses large language models as judges, validated against human annotators with comparable agreement levels. The authors also present an iterative simplification approach that produces definitions scoring highly on their criteria and exhibiting lexical simplicity.

By Yusuke Ide, Adam Nohejl, Joshua Tanner, Hitomi Yanaka, Christopher Lindsay, Taro Watanabe