Text to Speech



Text-to-Speech (TTS) service converts text into audio data. It accomplishes this by dividing the inputted text into sentences, words, and phonemes. It then converts the divided segments into speech signals and synthesizes those signals into audio data.


Process of TTS Engine

Operating order of TTS Engine


TTS service by LG AI Platform supports the following features:

Feature Description
Comprehensive analysis

Analyzes text inputted by the user, examining pronunciation, syllables, phrases, context, parts of speech, etc.

Advanced speech synthesis

Learns and restores audio signals based on artificial neural network technology, and generates voice data using Vocoder.
Speech synthesis is performed using long short-term memory (LSTM) and recurrent neural network (RNN) architecture.

Fast response time

Generates audio data as soon as the user inputs text.

Human-like speech

Employs natural, human-like speech using the latest deep learning technology.

Multi-language support

Supports Korean and English languages.

Voice selection

Allows the selection of voice gender according to user preferences.

Speech speed control

Offers five-speed levels to deliver speech output.

Pitch tuning

Customizes voice pitch according to user preferences.

Volume control

Offers ten levels of volume control.

Sound effect

Adds sound effects such as robotization and echo to voices according to preferences.



All functions of TTS service are run on a server. TTS service receives text and JSON data as input, and generates audio data output.


Architecture of NLP Engine


Examples of Use

TTS service can be used in a variety of situations that require voice-based services. TTS service can also be used to assist the visually impaired, narrate audiobooks, or elevate the functions of any application that plays voice audio.


  • Voice functionality for personal devices

TTS service can be used for a service that reads mobile texts to drivers.

Q Voice reads a text for a driver

  • Voice functionality for home appliances

Refrigerators equipped with TTS service can read cooking recipes aloud.

Refrigerator to read cooking recipes

  • Navigation voice service​

TTS service can enable a car navigation service to read directions to a destination entered into the system.

Navigation to read the destination and direction to the driver