Puheentekijäys

Puheentekijäys, often translated as "speech synthesis" or "text-to-speech" (TTS), is a technology that converts written text into spoken audio. This process involves analyzing the input text to understand its structure, pronunciation, and intonation, and then generating corresponding speech signals.

The core of puheentekijäys lies in several key stages. First, text normalization is performed to convert numbers, abbreviations, and symbols into their full word forms. Next, phonetic transcription assigns phonetic symbols to each word, representing how it should be pronounced. This is often followed by prosody generation, where information about rhythm, stress, and pitch is determined to create natural-sounding speech. Finally, waveform generation synthesizes the actual audio signal based on the phonetic and prosodic information.

Early puheentekijäys systems used concatenative synthesis, piecing together pre-recorded speech units. More modern approaches, like parametric synthesis and deep learning-based methods, utilize statistical models and neural networks to generate more fluid and human-like speech. These advancements have significantly improved the quality and expressiveness of synthesized voices.

Puheentekijäys has a wide range of applications. It is commonly found in assistive technologies for visually impaired individuals, allowing them to access written content aurally. It is also used in navigation systems, virtual assistants, audiobooks, and educational tools. The continuous development in this field aims to achieve even greater naturalness and expressiveness in synthesized speech.