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Vivox Core SDK

Vivox Core SDK

Vivox
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Vivox Core SDK
  • Overview
  • Before you begin
  • Get started
  • Release notes
  • Developer Guide
    • Client SDK basics
    • Channels
    • Presence management
    • Messaging
    • Manage audio
    • Couch co-op
    • Android app development
    • iOS app development
    • macOS app development
    • Windows app development
    • Real-time recording
    • Speech-to-text audio transcription
    • Text-to-speech
      • Initialize text-to-speech
      • Text-to-speech voice options
      • Text-to-speech destinations
      • Inject a text-to-speech message
      • Queue a text-to-speech message
      • Cancel a text-to-speech message
      • Text-to-speech events
      • Get raw audio of synthesized speech
      • Use text-to-speech for incoming messages
      • Shut down text-to-speech
    • Troubleshooting
  • Reference
  • Privacy overview
  1. Vivox Core SDK documentation
  3. Text-to-speech

Text-to-speech events

Learn about text-to-speech event callbacks.
Read time 1 minute
Last updated 8 months ago
Text-to-speech (TTS) reports the following events through the standard Vivox events reporting mechanism:
  • vx_evt_tts_injection_started
     - Raised when a TTS message has finished preparing for playback and is starting to play.
    • num_consumers
      - The number of active sessions (for 
      tts_dest_remote_transmission
      ) or local playback players (for 
      tts_dest_local_playback
      ) that the TTS message is injected into.
    • utterance_id
      - The unique identifier of the TTS message or utterance. This is the same identifier as the one that is returned to you when calling 
      vx_tts_speak
      .
    • utterance_duration
      - The duration of the utterance in seconds.
    • tts_destination
      - The destination into which the TTS message is injected.
  • vx_evt_tts_injection_ended
     - Raised when a TTS message finishes playback.
    • num_consumers
      - The number of active sessions (for 
      tts_dest_remote_transmission
      ) or local playback players (for 
      tts_dest_local_playback
      ) that the TTS message is injected into.
    • utterance_id
      - The unique identifier of the TTS message or utterance. This is the same identifier as the one that is returned to you when calling 
      vx_tts_speak
      .
    • tts_destination
      - The destination into which the TTS message is injected.
  • vx_evt_tts_injection_failed
     - Raised when playback of a TTS message has failed.
    • status
      - The error code of the failure.
    • utterance_id
      - The unique identifier of the TTS message or utterance. This is the same identifier as the one that is returned to you when calling 
      vx_tts_speak
      .
    • tts_destination
      - The destination into which the TTS message is injected.
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