Now showing items 1-10 of 15

    • Bilateral G2P accuracy: measuring the effect of variants 

      Giwa, Oluwapelumi; Davel, Marelie H. (Pattern Recognition Association of South Africa and Mechatronics International Conference, 2017)
      Incorporating pronunciation variants in a dictionary is controversial, as this can be either advantageous or detrimental for a speech recognition system. Grapheme-tophoneme (G2P) accuracy can help guide this decision, ...
    • Category-based phoneme-to-grapheme transliteration 

      Basson, Willem D.; Davel, Marelie H. (International Speech Communication Association ( ISCA ), 2013)
      Grapheme-based speech recognition systems are faster to develop but typically do not reach the same level of performance as phoneme-based systems. In this paper we introduce a technique for improving the performance of ...
    • Collecting and evaluating speech recognition corpora for 11 South African languages 

      Badenhorst, Jaco; Van Heerden, Charl; Barnard, Etienne; Davel, Marelie H. (Springer, 2011)
      We describe the Lwazi corpus for automatic speech recognition (ASR), a new telephone speech corpus which contains data from the eleven official languages of South Africa. Because of practical constraints, the amount of ...
    • Comparing grapheme-based and phoneme-based speech recognition for Afrikaans 

      Basson, Willem D.; Davel, Marelie H. (PRASA, 2012)
      This paper compares the recognition accuracy of a phoneme-based automatic speech recognition system with that of a grapheme-based system, using Afrikaans as case study. The first system is developed using a conventional ...
    • Efficient harvesting of Internet audio for resource-scarce ASR 

      Davel, Marelie H.; van Heerden, Charl; Kleynhans, Neil; Barnard, Etienne (Interspeech 2011, 2011)
      Spoken recordings that have been transcribed for human reading (e.g. as captions for audiovisual material, or to provide alternative modes of access to recordings) are widely available in many languages. Such recordings ...
    • G2P variant prediction techniques for ASR and STD 

      Davel, Marelie H.; van Heerden, Charl; Barnard, Etienne (Interspeech 2013, 2013)
      Introducing pronunciation variants into a lexicon is a balancing act: incorporating necessary variants can improve automatic speech recognition (ASR) and spoken term detection (STD) performance by capturing some of the ...
    • Implications of Sepedi/English code switching for ASR systems 

      Modipa, Thipe I.; De Wet, Febe; Davel, Marelie H. (Pattern recognition association of South Africa (PRASA), 2013)
      Code switching (the process of switching from one language to another during a conversation) is a common phenomenon in multilingual environments. Where a minority and dominant language coincide, code switching from the ...
    • Introduction to the special issue on processing under-resourced languages 

      Besacier, L.; Barnard, E.; Karpov, A.; Schultz, T. (Speech Communications, 2014)
      The creation of language and acoustic resources, for any given spoken language, is typically a costly task. For example, a large amount of time and money is required to properly create annotated speech corpora for automatic ...
    • Medium-vocabulary speech recognition for under-resourced languages 

      Van Heerden, Charl J.; Barnard, Etienne; Davel, Marelie H. (SLTU, 2012)
      We report on the development of speech-recognition systems that are able to perform accurate recognition on mediumvocabulary tasks (i.e. tasks that require distinctions between approximately 200 different terms). We are ...
    • The NCHLT Speech Corpus of the South African languages 

      Barnard, Etienne; Davel, Marelie H.; van Heerden, Charl; De Wet, Febe; Badenhorst, Jaco (Workshop Spoken Language Technologies for Under-resourced Languages (SLTU), 2014)
      The NCHLT speech corpus contains wide-band speech from approximately 200 speakers per language, in each of the eleven official languages of South Africa. We describe the design and development processes that were ...