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Integrating a State-of-the-Art ASR System into the Opencast Matterhorn Platform

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Advances in Speech and Language Technologies for Iberian Languages


In this paper we present the integration of a state-of-the-art ASR system into the Opencast Matterhorn platform, a free, open-source platform to support the management of educational audio and video content. The ASR system was trained on a novel large speech corpus, known as poliMedia, that was manually transcribed for the European project transLectures. This novel corpus contains more than 115 hours of transcribed speech that will be available for the research community. Initial results on the poliMedia corpus are also reported to compare the performance of different ASR systems based on the linear interpolation of language models. To this purpose, the in-domain poliMedia corpus was linearly interpolated with an external large-vocabulary dataset, the well-known Google N-Gram corpus. WER figures reported denote the notable improvement over the baseline performance as a result of incorporating the vast amount of data represented by the Google N-Gram corpus.

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  1. UPVLC, XEROX, JSI-K4A, RWTH, EML, DDS: transLectures: Transcription and Translation of Video Lectures. In: Proc. of EAMT, p. 204 (2012)

    Google Scholar 

  2. Zhan, P., Ries, K., Gavalda, M., Gates, D., Lavie, A., Waibel, A.: JANUS-II: towards spontaneous Spanish speech recognition 4, 2285–2288 (1996)

    Google Scholar 

  3. Nogueiras, A., Fonollosa, J.A.R., Bonafonte, A., Mariño, J.B.: RAMSES: El sistema de reconocimiento del habla continua y gran vocabulario desarrollado por la UPC. In: VIII Jornadas de I+D en Telecomunicaciones, pp. 399–408 (1998)

    Google Scholar 

  4. Huang, X., Alleva, F., Hon, H.W., Hwang, M.Y., Rosenfeld, R.: The SPHINX-II Speech Recognition System: An Overview. Computer, Speech and Language 7, 137–148 (1992)

    Article  Google Scholar 

  5. Speech and Language Technology Group. Sumat: An online service for subtitling by machine translation (May 2012),

  6. Broman, S., Kurimo, M.: Methods for combining language models in speech recognition. In: Proc. of Interspeech, pp. 1317–1320 (2005)

    Google Scholar 

  7. Liu, X., Gales, M., Hieronymous, J., Woodland, P.: Use of contexts in language model interpolation and adaptation. In: Proc. of Interspeech (2009)

    Google Scholar 

  8. Liu, X., Gales, M., Hieronymous, J., Woodland, P.: Language model combination and adaptation using weighted finite state transducers (2010)

    Google Scholar 

  9. Goodman, J.T.: Putting it all together: Language model combination. In: Proc. of ICASSP, pp. 1647–1650 (2000)

    Google Scholar 

  10. Lööf, J., Gollan, C., Hahn, S., Heigold, G., Hoffmeister, B., Plahl, C., Rybach, D., Schlüter, R., Ney, H.: The rwth 2007 tc-star evaluation system for european english and spanish. In: Proc. of Interspeech, pp. 2145–2148 (2007)

    Google Scholar 

  11. Rybach, D., Gollan, C., Heigold, G., Hoffmeister, B., Lööf, J., Schlüter, R., Ney, H.: The rwth aachen university open source speech recognition system. In: Proc. of Interspeech, pp. 2111–2114 (2009)

    Google Scholar 

  12. Stolcke, A.: SRILM - An Extensible Language Modeling Toolkit. In: Proc. of ICSLP (2002)

    Google Scholar 

  13. Michel, J.B., et al.: Quantitative analysis of culture using millions of digitized books. Science 331(6014), 176–182

    Google Scholar 

  14. Turro, C., Cañero, A., Busquets, J.: Video learning objects creation with polimedia. In: 2010 IEEE International Symposium on Multimedia (ISM), December 13-15, pp. 371–376 (2010)

    Google Scholar 

  15. Barras, C., Geoffrois, E., Wu, Z., Liberman, M.: Transcriber: development and use of a tool for assisting speech corpora production. Speech Communication Special Issue on Speech Annotation and Corpus Tools 33(1-2) (2000)

    Google Scholar 

  16. Apache. Apache felix (May 2012),

  17. Osgi alliance. osgi r4 service platform (May 2012),

  18. Sahidullah, M., Saha, G.: Design, analysis and experimental evaluation of block based transformation in MFCC computation for speaker recognition 54(4), 543–565 (2012)

    Google Scholar 

  19. Gascó, G., Rocha, M.-A., Sanchis-Trilles, G., Andrés-Ferrer, J., Casacuberta, F.: Does more data always yield better translations? In: Proc. of EACL, pp. 152–161 (2012)

    Google Scholar 

  20. Sánchez-Cortina, I., Serrano, N., Sanchis, A., Juan, A.: A prototype for interactive speech transcription balancing error and supervision effort. In: Proc. of IUI, pp. 325–326 (2012)

    Google Scholar 

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Valor Miró, J.D., Pérez González de Martos, A., Civera, J., Juan, A. (2012). Integrating a State-of-the-Art ASR System into the Opencast Matterhorn Platform. In: Torre Toledano, D., et al. Advances in Speech and Language Technologies for Iberian Languages. Communications in Computer and Information Science, vol 328. Springer, Berlin, Heidelberg.

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