TomTom SDK for iOS SystemTextToSpeechEngine

SystemTextToSpeechEngine

public class SystemTextToSpeechEngine : TextToSpeechEngine

Provides text-to-speech capabilities using the system’s speech synthesis engine. Converts text into speech using the specified language and optional gender preferences.

This class leverages the AVSpeechSynthesizer to convert text messages into spoken voice. It allows customization of the voice’s language and gender. It supports various message formats, including plain text and Speech Synthesis Markup Language (SSML).

You could use the following code to check if the specific voice for the given language is present on your device or not.

import AVFoundation

let languageCode = "en-US" // you can change this to the desired language code
if SystemTextToSpeechEngine.isVoiceAvailable(for: languageCode) {
    // Creates an instance of ``SystemTextToSpeechEngine``
} else {
    // Guide the user to download the voice or use a fallback
}

For more details about the AVSpeechSynthesisVoice read the Apple documentation: https://developer.apple.com/documentation/avfaudio/avspeechsynthesisvoice

Important

This is a Public Preview API. It may be changed or removed at any time.

  • Initializes a new instance of SystemTextToSpeechEngine.

    The initializer will throw an error if voices are not downloaded to the iOS device.

    Throws

    TextToSpeechEngineError.unavailableLocaleInVoices if there is no speech voice for the given language.

    Declaration

    Swift

    public init(language: Locale = Locale(identifier: "en_US"), gender: AVSpeechSynthesisVoiceGender? = nil) throws

    Parameters

    language

    Identifies in which language the voice instructions will be spoken. The default is Locale(identifier: "en_US").
    gender

    The gender for a voice. If nil, the default gender voice available for the specified language will be used.

  • Supported phonetic alphabets.

    Declaration

    Swift

    public var supportedAlphabets: [String]

  • A locale that defines the voice’s language.

    Declaration

    Swift

    public var locale: Locale { get }

  • The delegate object that receives text-to-speech engine events.

    Declaration

    Swift

    public weak var delegate: TextToSpeechEngineDelegate? { get set }

  • Checks if a specific language is available for text-to-speech.

    Declaration

    Swift

    public static func isLanguageAvailable(for locale: Locale) -> Bool

    Parameters

    locale

    The locale representing the language to check.

    Return Value

    true if the language is available; otherwise, false.

  • Plays a text-to-speech message.

    Declaration

    Swift

    public func play(message: TTSMessage)

    Parameters

    message

    The message to be converted into speech.

  • Stops the text-to-speech playback.

    Declaration

    Swift

    public func stop()

  • Sets the speech volume.

    Declaration

    Swift

    public func setVolume(_ volume: SpeechVolume)

  • Sets the language code of the messages.

    Throws

    TextToSpeechEngineError.unavailableLocaleInVoices if there is no speech voice for the given locale.

    Declaration

    Swift

    public func changeLocale(with locale: Locale) throws

    Parameters

    locale

    The locale representing the new language.