RealtimeTTS and pyttsx3
Both tools provide offline text-to-speech capabilities for Python, but pyttsx3 serves as a general-purpose library leveraging system-level speech engines, while RealtimeTTS focuses on real-time, low-latency synthesis specifically designed for scenarios where immediate audio output is critical.
About RealtimeTTS
KoljaB/RealtimeTTS
Converts text to speech in realtime
Supports 15+ TTS engines (OpenAI, Elevenlabs, Azure, Coqui, Piper, and local models) with automatic fallback mechanisms for reliability, enabling flexible deployment from cloud APIs to on-device processing. Features sentence-boundary detection via NLTK or Stanza for streaming text inputs compatible with LLM outputs, minimizing latency while maintaining natural speech segmentation across multilingual content.
About pyttsx3
nateshmbhat/pyttsx3
Offline Text To Speech synthesis for python
Abstracts platform-specific TTS engines (SAPI5 on Windows, eSpeak on Linux, AVSpeech/NSSpeechSynthesizer on macOS) behind a unified Python API, enabling voice selection, rate/volume control, and audio file export. The library provides both synchronous and file-saving modes, with configurable speech properties accessible through a simple property getter/setter interface.
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