{ "Engine": "generative", "LanguageCode": "en-US", "LexiconNames": [ "Joanna" ], "OutputFormat": "mp3", "SampleRate": "24000", "SpeechMarkTypes": [ "viseme" ], "Text": "Hello, this is a sample text for speech synthesis.", "TextType": "ssml", "VoiceId": "voice-292" }