With 23 official languages, European institutions spend more than a billion euros a year translating documents and interpreting speeches. Companies trading across the EU’s internal borders spend millions more just to understand their business partners.
The situation, unparalleled anywhere else in the world, makes Europe a natural market for automatic translation technology, and, logically, a leader in the development of systems that can help speakers of different languages communicate.
“There is an evident need for this sort of technology in Europe and elsewhere in the world… it saves time and costs over human
translation,” explains Marcello Federico, a researcher at FBK-irst in Trento, Italy.
But no one has been able to develop an automatic translation system that comes anywhere close to the capabilities of a human translator or interpreter. Internet translations are a case in point, littered with punctuation errors, misplaced words and grammatical mistakes that can make them almost unintelligible.
Other systems can only translate certain predefined words and phrases, so-called ‘constrained speech’ that suffices for a tourist booking a hotel or checking flight times but is next to useless if you want to understand a news bulletin.
Federico led a team that sought to achieve something far more ambitious. Working in the EU-funded TC-STAR project they tackled what is perhaps the biggest human language technology challenge of all: taking speech in one language and outputting spoken words in another.
First in speech-to-speech translation
“For humans, translation is difficult. We have to master both the source language and the target language, and machine translation is significantly more difficult than that,” Federico notes. “To our knowledge, TC-STAR has been the first project in the world addressing unrestricted speech-to-speech translation.”
For such a system to be able to translate any speech regardless of topic and context, three technologies are used, all of which are still far from perfect. Automatic Speech Recognition (ASR) is used to transcribe spoken words to text. Spoken Language Translation (SLT) translates the source language to the target language. Text to Speech (TTS) synthesises the spoken output.
The TC-STAR research partners developed components to handle each of those tasks, creating a platform that has brought the state of the art of translation technology a step closer to matching the performance of human translators.