What is Text to speech?
{{listen|filename=JärDa-utrop.ogg|title=Automatic announcement|description=A synthetic voice announcing an arriving train in [[Sweden]].|format=[[Ogg]]}}'''Text to speech''' (TTS) is the use of [[software]] to create a [[sound]] [[output]] in the form of a spoken [[voice]]. The program that is used by programs to change text on the page to an audio output of the spoken voice is normally a text to speech engine. [[Blindness|Blind]] people, people [[Visual impairment|who do not see well]], and people with [[Dyslexia|reading disabililties]] can rely on good text-to-speech systems. That way they can listen to pieces of the text. TTS engines are needed for an audio output of [[machine translation]] results. Up until about 2010, there was the analytic approach: This approach uses multiply steps to convert the text to speech. Usually, an input text is transformed into [[phonetic writing]]. This says how the words are pronounced, and not how they are written. In the phonetic writing, [[Phoneme|phonemes]] can be identified. The system can then produce speech by putting together prerecorded or synthesized [[Diphone|diphones]]. A problem is to make the language flow sound natural, what linguists call [[Prosody (linguistics)|prosody]]. As of 2022, [[deep learning]] is used. To get a good result, [[Artificial neural network|neural networks]] are trained with many good [[Sample|samples]]. Historically, the first systems for speech synthesis used [[Formant|formants]]. Industrial Systems today, mostly use signal processing. == History == [[File:Kempelen Speakingmachine.JPG|thumb|Reconstruction of Kempelen's speaking machine]] [[File:Synthesizer after Helmholtz by Koenig 1865.jpg|thumb|Copy of the machine proposed by Helholz]] [[File:Bell telephone magazine (1922) (14733635746).jpg|thumb|Demonstration of the Voder, by Bell Labs]] Long before there was [[electronic signal processing]], people tried to build machines that were capable of producing human speech. Gerbert of Aurillac (the future [[Pope Sylvester II]]) is said to