APP FROM : ''TWO GREAT CZECH UNIVERSITIES"

NEW APP gives throat cancer patients their voice back.

Vlastimil Gular's life took an unwelcome turn a year ago: minor surgery on his vocal chords led to the loss of his larynx and with it, his voice.

But the 51-year old father of four is still chatting away using own voice rather than the tinny timber of robot, thanks to an innovative app developed by two Czech universities.

''I find this very useful,'' Gular told AFP, using app to type in what he wanted to say, in his own voice by a mobile phone.

''I'm not very good at using the voice prosthesis,'' he added, pointing at the hole the size of a large coin in his throat.

This small silicon device implanted in the throat allows people to speak by pressing the hole with their fingers to regulate airflow through the prosthesis and so create sound.

But Gular prefers the new tech hi-tech voice app.

It was developed for  patients set to lose their voice due to a  laryngectomy or removal of the larynx, a typical procedure for advanced stages of throat cancer.

The joint project of the University of  West Bohemia in Pilsen, Pargue's Charles University and two private companies - CertiCon and SpeechTech - kicked off nearly two years ago.

The technology uses recordings of a patient's voice to create synthetic speech that can be played on their mobile phones, tablets or laptops via the app.

Ideally, patients need to record more than 10,000 sentences to provide scientists with enough material to produce their synthetic voice.

''We edit together individual sounds of speech of sound so we need a lot of sentences,'' said Jindrich Matunsek, an expert on text-to-speech synthesis, speech medelling and  acoustics who heads the project at the Pilsen University.

''A Matter of Weeks'' : But there are drawbacks : Patients facing laryngectomies usually have little time or energy to do the recordings in the wake of a diagnosis that requires swift treatment.

''It's usually matter of weeks,'' said Barbora Repova, a director at the Motol University Hospital, working on the project,'' for Charles University.

To address these difficulties, scientists came up with more streamlined method for the app, which is supported by the Technology Agency of Czech Republic.

Working with fewer sentences - ideally, 3,500 but as few as 300 - this method uses advanced statistical models such as artificial neural networks.

''You use speech models with certain parameters to generate synthesised speech,'' said Matousek.

''Having more data is still better,but you can achieve decent quality with less data of a given voice.''

The sentences are carefully selected and individual sounds have to be recorded several times as they are pronounced differently next to different   sounds or at the beginning and end of a word or sentence, he added.

So far, the Pilsen University has recorded 10 to 15 patients, according to Matousek.

Besides Czech, the Pilsen scientists have also created synthesised speech samples in English, Russian and Slovak.

'Baby Dinosaurs' : Gular an upholsterer who lost his job due to the handicap - managed to record  477 sentences over the three weeks between his diagnosis and the operation

But he was stressed and less than satisfied with the quality of his voice. ''Throat cancer patients often suffer from some form of  dysphonia [hoarseness]  before the surgery,  so in combination with a limited speech sample it makes the voice sound unnatiral,'' said Repova.

In a studio at the Pilsen university meanwhile, entrepreneurs Jans Huttova is recording outlandish phrases. [Agencies]