G o S t- P ar C -Sign: Gold Standard Parallel Corpus of Sign and spoken language (2023)

Abstract: Good quality training data for Sign Language Machine Translation (SLMT) is extremely scarce, and this is one of the challenges that any project focusing on Machine Translation (MT) which also targets sign languages is currently facing. The goal of this ongoing project is to create a parallel corpus of authentic Flemish Sign Language (VGT) and written Dutch which can be employed as gold standard in automated sign language translation. The availability of a gold standard corpus like Gost-ParC-Sign can facilitate the advances of SLMT; consequently, it supports and promotes inclusiveness in MT and, on a more general level, in language technology

## introduction in the last decade, there has been an increasing interest in extending mt from only focusing on spoken languages (spls) to also targeting sign languages (sls); nevertheless, the advances of this field are still limited, and this is due to a number of reasons (e.g. challenges related to data availability, lack of notation conventions, etc.). besides the technological gap between splmt and slmt, a severe difference lies in the availability of high-quality (training) data. splmt can count on open and free datasets, such as europarl @xcite and opus @xcite , and on several mt platforms which allow training on specific datasets. 1 the availability of sufficient amounts of high-quality (training) data drives the mt performance up. furthermore, well-designed test sets allow to adequately assess quality and fairly compare mt systems. for sls, instead, training data is scarce and scattered. parallel datasets, with one side in a sl and the other in a spl, are extremely limited. in addition, most of the available datasets consist in broadcasts with subtitles/autocues as a written form of a spl as the source and interpretation into a sl as the target @xcite ; this leads to various concerns related to their quality: sl as the result of interpretation or translation is heavily influenced by the source language foot_1 as well as by the interpreting process; in addition, even though in some cases hearing interpreters are coda's (children of deaf adults), most often the interpretation is made by a hearing interpreter for whom the sl is the l2. in some cases, corpora with sl as source are available, such as the corpus vlaamse gebarentaal foot_2 (vgt) @xcite (corpus of flemish sign language); nevertheless, as annotation of the data is ongoing, the translations available are too insufficient for quality (automatic) sl translation (slt). additionally, as the data contain videos of the signer's faces, strict gdpr rules apply, and signed informed consent forms are required from each of the signers. the signon project foot_3 aims to build slt engines and hence gathers available sl data; throughout this process, we faced a number of issues, foot_4 which led us to identify the need for a gold standard parallel corpus of sl -spl. the collection, organisation and (public) release of such a corpus, will provide a common ground for advancing the field of slt. ## gost-parc-sign the goal of this project is to create a gold standard parallel corpus of authentic vgt as source and a translation into written dutch as target language. this 12-month project, running between february 2023 and january 2024, consists of three phases: (1) collection of existing source sl videos in vgt and of informed consent forms from their signers. 6 (2) manual translation of the sl into written dutch, performed by a mixed team of deaf and hearing professional vgt translators; this will optimize the translation process, preserve the content of the original message, and ensure good quality of the dutch text. this phase will consist of 133 hours of translation work, foot_6 resulting in approximately at least 9-10 hours of video being translated. 8 translations will be created in elan @xcite . translations will be arranged into a "translation" tier in the elan annotation format (eaf) file of each corresponding video. since there is no sign-to-word correspondence between vgt and dutch, alignment is at the sentence or message level. (3) quality control by members of the flemish deaf community and l1 dutch language users, which will ensure that the translations made convey the same message as the original videos. all phases will be overseen by the vlaams gebarentaalcentrum (vgtc) and ku leuven, both members of signon, in order to ensure data and translation quality. the final corpus will be made publicly available (with a creative commons by licence) through the clarin infrastructure at the instituut voor de nederlandse taal (int), and through the european language grid. ## current and future steps in this initial phase of gost-parc-sign approximately 10 hours of authentic vgt videos to be translated into written dutch have been identified. the videos cover different topics and genres: 5 hours of free conversation, a 1,5 hour panel discussion about linguistic change in the community, over 2 hours of a deaf-lead talk, a game show to celebrate 15 years of recognition for vgt, and 45 minutes of semi-spontaneous vlogs about typical language uses in vgt. they all constitute content originally produced for a signing audience. vgtc has recruited translators and we are currently collecting signed informed consents from the video's owners. after phase 1, the translation phase will start; the quality control, i.e. phase 3, will follow between august and december 2023. in the final month of the project we will prepare and release