Interspeech 2016 Special Session

Sub-Saharan African languages : from speech fundamentals to applications


Martine Adda-Decker1 ( – CNRS – LPP and LIMSI, France.

Laurent Besacier2 ( – Univ. Grenoble-Alpes, France – LIG laboratory.

Marelie Davel3 ( – North-West University, Vanderbijlpark, South Africa.

Larry Hyman4 ( – Department of Linguistics, University of California, Berkeley.

Martin Jansche5 ( – Google, London, UK.

Francois Pellegrino6 ( – CNRS – DDL Lyon, France.

Olivier Rosec7 ( – Voxygen SAS,- Pleumeur-Bodou, France.

Sebastian Stüker8 ( – Karlsruhe Institute of Technology (KIT), Germany.

Martha Tachbelie Yifiru9 ( – School of Information Science, Addis Ababa University, Ethiopia.


The number of languages spoken in Africa ranges from 1,500 to 2,500, depending on estimates and definitions. Africa is a place of rich — if not the richest — linguistic diversity which is often related to Africa’s being the cradle of humanity. Political explanations also go in favor of high linguistic diversity: during the 19th century, the many ethnic groups existing in Africa were divided into different countries according to colonial borders, resulting in cross-border languages. Multilingualism is thus ubiquitous in Sub-Saharan African societies.

In recent years, many institutions and organizations have been created to develop and standardize spoken and written resources in many languages (not only the higher-resourced ones), to provide multilingual access to digital resources and to promote national languages in the digital space. Coming to economical considerations, a major challenge of the digital market in Africa is to ensure that online applications and services become accessible to a wide range of people, be they literate or not. For the latter ones, applications should be able to talk and listen to Africans in the true sense of the words and several UNESCO reports make explicit reference to text to speech synthesis (TTS) and automatic speech recognition (ASR) as a technological facilitator. People’s access to ICT is done mainly through mobile phones and the need for voice services can be found in all sectors, from high priority (health, food, information) to more fun and leisure (sports, games, social media) areas. Beyond speech technologies, language documentation is another priority pointed out by UNESCO, since some languages in the Sub-Saharan Africa are seriously endangered with the risk of disappearing in the coming years.

However, progress in speech and language technologies in African languages suffers from a lack in linguistic knowledge and basic NLP resources. Now is the right time to bring speech technology and linguistic researchers together for the benefit of sharing fundamental linguistic knowledge and language resources, as well as technological, societal and economical progress.

To address these goals (language documentation, development of speech and language resources and technologies in African languages), inter-disciplinary research is required: from fundamentals of speech analysis (acoustic-phonetic, tonal and other linguistic descriptions, dialectology and typology) to speech technologies (ASR, TTS…). Speech and language technologies may also contribute to open up new perspectives in empirical linguistic research with new tools and approaches speeding up corpus and metadata production, language documentation of poorly studied languages, treating unwritten languages, thus contributing to the struggle against loss of language diversity in Africa.

To summarize, this special session aims at gathering researchers in speech technology (automatic speech recognition, text-to-speech synthesis…) and researchers in linguistics (field linguists, phoneticians…) working in language documentation and fundamentals of speech science. We believe that such a partnership is particularly important for Sub-Saharan African languages which tend to remain under-resourced, under-documented and often also un-written. While a minimum language description kit required to develop speech technologies cannot be obtained without linguistic research, automatic speech technology offers novel opportunities and tools to linguists for speeding up investigations in a wide range of topics in phonetics, phonology, tonology, morphology…

Possible contributors to the special session

Many researchers / institutions could submit a paper to this special session. In addition to the organizers of this session, the potential contributors can be found among the following projects, academic or industrial research groups :

  • Academic researchers working in Africa on their mother tongue language (such a session would be also a great opportunity to increase the participation of African researchers to Interspeech and to ISCA association),

  • Industrial research centers developing ASR and TTS for many languages (Google, Amazon, Microsoft, Facebook, etc.),

  • BULB project (Breaking the Unwritten Language Barrier) : KIT, LIMSI, LIG, ZAS, LPP, LLACAN,

  • BABEL project (IARPA program) : many partners from US, Europe and South-Africa,

  • ALFFA project (African Languages in the Field – Speech Fundamentals and Automation) : LIG, DDL, LIA, Voxygen SAS

Session format

The session will consist of very-short oral presentations (2mn booster) followed by a poster-session. The best papers will be encouraged to be submitted to a special issue in a journal (Speech Communication or Computer Speech and Language).

Call for papers

Prospective authors are invited to submit original papers in areas related to Sub-Saharan African languages science and technology including but not limited to :

  • Speech recognition for Sub-Saharan African languages and dialects

  • Text-to-speech synthesis for Sub-Saharan African languages and dialects

  • Cross-lingual and multi-lingual acoustic and lexical modeling

  • Applications of spoken language technologies for the African continent

  • Phonetic and linguistic studies in Sub-Saharan African languages

  • Zero resource speech technologies: unsupervised discovery of linguistic units

  • Language documentation for endangered languages of Africa

  • Machine-assisted annotation of speech and laboratory phonology

  • Resource production in African languages: text and speech corpora, lexica, language models

1Research Director at CNRS. Inter-disciplinary research in speech technologies and corpus phonetics.

2Founder of the bi-annual SLTU workshop series (Spoken Language Technologies for Under-resourced languages). Research on spoken language technologies for low-resourced (including Sub-Saharan African) languages.

3Director of the Multilingual Speech Technologies research group at North-West University in South Africa. Language technology development for under-resourced languages, with a focus on Southern African languages.

4Professor of Linguistics in the Department of Linguistics at the University of California at Berkeley. He is a specialist in phonology, typology, and African linguistics, particularly Bantu and other Niger-Congo.

5Software Engineer, Google Research for Low Resource Languages, Google London.

6Former director of the ‘Dynamique Du Langage’ Laboratory (DDL) and coordinator of the ‘laboratory of excellence’ ASLAN (Advanced Studies on Language complexity).

7R&D director of Voxygen SAS. Specialist of Text-to-speech synthesis. Current developments and interests involve Sub-Saharan African languages.

8Coordinator of the ANR-DFG BULB project (Breaking the Unwritten Language Barrier). Research on spoken language technologies at KIT.

9Head of the School of Information Sciences, Addis Ababa University (Ethiopia). ASR and NLP for Amharic lang.