Speech Translation

Speech Translation

Automatic translation of speech practically sub-titles – in your native language! – the speech of foreign-language speakers.

Target users and customers

  • Researchers
  • Developers
  • Integrators

Application sectors

  • Sub-titling of broadcast via television or internet
  • Internet search in audio and video material (cross-language retrieval)


In a nutshell, speech translation is the combination of two hard computer science problems, namely speech recognition (automatic transcription of speech into text) and machine translation (automatic translation of a text from a source to a target language).

While both technologies do not work perfectly, it is impressive to see them working in combination, in particular when we have not even rudimentary knowledge of the source language – for many of us, this is the case for the Chinese or the Arabic language. The mathematical methods behind both speech recognition and machine translation are related, and the systems draw their knowledge from large amounts of example data.

Technical requirements:

Speech translation is a computationally and memory-intensive process, so the typical set-up is to have one or several computers in the internet serving the speech translation requirements of many users.

Conditions for access and use:

RWTH provides on open-source speech recognizer and various open-source tools free of charge for academic usage. Other usage should be subject to a bilateral agreement.

Bildschirmfoto vom 2013-07-23 183A183A46


  • RWTH Aachen

Contact details:

Volker Steinbiss

RWTH Aachen University
Lehrstuhl für Informatik 6
Templergraben 55
52072 Aachen