Building a Unified Code-Switching ASR System for South African Languages

Emre Yılmaz, Astik Biswas, Ewald van der Westhuizen, Febe de Wet, Thomas Niesler


We present our first efforts towards building a single multilingual automatic speech recognition (ASR) system that can process code-switching (CS) speech in five languages spoken within the same population. This contrasts with related prior work which focuses on the recognition of CS speech in bilingual scenarios. Recently, we have compiled a small five-language corpus of South African soap opera speech which contains examples of CS between 5 languages occurring in various contexts such as using English as the matrix language and switching to other indigenous languages. The ASR system presented in this work is trained on 4 corpora containing English-isiZulu, English-isiXhosa, English-Setswana and English-Sesotho CS speech. The interpolation of multiple language models trained on these language pairs enables the ASR system to hypothesize mixed word sequences from these 5 languages. We evaluate various state-of-the-art acoustic models trained on this 5-lingual training data and report ASR accuracy and language recognition performance on the development and test sets of the South African multilingual soap opera corpus.


 DOI: 10.21437/Interspeech.2018-1966

Cite as: Yılmaz, E., Biswas, A., van der Westhuizen, E., de Wet, F., Niesler, T. (2018) Building a Unified Code-Switching ASR System for South African Languages. Proc. Interspeech 2018, 1923-1927, DOI: 10.21437/Interspeech.2018-1966.


@inproceedings{Yılmaz2018,
  author={Emre Yılmaz and Astik Biswas and Ewald {van der Westhuizen} and Febe {de Wet} and Thomas Niesler},
  title={Building a Unified Code-Switching ASR System for South African Languages},
  year=2018,
  booktitle={Proc. Interspeech 2018},
  pages={1923--1927},
  doi={10.21437/Interspeech.2018-1966},
  url={http://dx.doi.org/10.21437/Interspeech.2018-1966}
}