Synthetic speech to aid announcements

Public announcements in noisy places, such as airports, could be made quieter and clearer, thanks to Edinburgh research.

Scientists have developed software that can alter speech before it is broadcast over speakers, making it more audible amid background noise.

In a bid to improve current synthetic voice technology, researchers studied how speech was perceived by listeners.

Effective listening

Noisy environments make it difficult to understand what is being said and simply making speech louder isn’t the smartest solution.
Dr Cassia Valentini BotinhaoSchool of Informatics

Researchers carried out tests to pinpoint the components of speech that are most easily heard by people in a noisy place.

University experts who carried out the study say that in loud situations, listeners pay most attention the parts of speech that are easiest to hear, and use those to decipher what is being said.

Researchers developed a mathematical computer program to analyse spoken words and enhance the sounds that help listeners hear what is being said, to make speech better understood overall.

Less volume

In tests, the manipulated speech was found to be much easier to understand than natural speech.

In some cases, the improvement was the equivalent of lowering noise by five decibels.

Scientists say that the techniques used in this study could also be used to improve smartphone voices, loudspeaker announcements or sat-nav systems.

The study, carried out with scientists from Greece, Spain and Sweden, was funded by the EU, and presented at the recent Interspeech 2013 conference in Lyon.

Our findings could offer an alternative, by making speech more intelligible without turning up the volume.”
Dr Cassia Valentini BotinhaoSchool of Informatics