v1.0.0

RealtimeSTT v1.0.0

Major Features

• New Transcription Engine System

  • Added a lazy-loaded engine abstraction under RealtimeSTT/transcription_engines.
  • faster_whisper remains the compatibility default.
  • Final and realtime transcription can now use different backends via transcription_engine and realtime_transcription_engine.
  • Backend-specific settings can be passed separately with transcription_engine_options and realtime_transcription_engine_options.

• New ASR Engines

  • Added whisper_cpp through pywhispercpp.
  • Added openai_whisper for OpenAI’s local Whisper package.
  • Added Moonshine, NVIDIA Parakeet/NeMo, Granite Speech, Qwen3-ASR, and Cohere Transcribe adapters.
  • Added CPU INT8 sherpa-onnx paths for Parakeet and Moonshine.
  • Added optional Kroko-ONNX aliases: kroko_onnx, kroko, and banafo_kroko.

• FastAPI Browser Streaming Server

  • Added example_fastapi_server, a browser-based streaming STT server with binary WebSocket audio input.
  • Added multi-user support with session-local audio buffers, VAD state, transcript state, segment IDs, clear/reset, warnings, errors, realtime text, and final text.
  • Heavy ASR models are shared through final/realtime inference lanes instead of loading one model per browser session.
  • Added fair per-session scheduling, realtime coalescing, stale realtime job dropping, final-job preservation, capacity limits, /health, /api/config, and /api/metrics.
  • Added wake-word support in the FastAPI server, including Porcupine/OpenWakeWord options and a follow-up window after wake activation.

• Syllable-Boundary Realtime Scheduling

  • Added optional CPU-only acoustic boundary scheduling with realtime_transcription_use_syllable_boundaries.
  • The scheduler triggers realtime ASR near likely syllable/vowel boundaries, with configurable sensitivity and follow-up delays.
  • In the reference fixture, realtime ASR calls dropped from 239 to 44, an 81.6% reduction, while final WER stayed at 0.000.

Improvements

• Customizable Installation

  • pip install RealtimeSTT now installs the core recorder, audio, WebRTC VAD, and Silero VAD dependencies.
  • Optional ASR and wake-word stacks are exposed as extras, including faster-whisper, whisper-cpp, openai-whisper, sherpa-onnx, parakeet, qwen, porcupine, openwakeword, wakewords, recommended, and all.
  • Wake-word dependencies are no longer mandatory unless selected. WebRTC VAD and Silero VAD remain core dependencies because the recorder still initializes both VAD paths.

• Realtime Text Stability

  • Added a structured RealtimeTextStabilizer with stable deltas, unstable preview text, outlier handling, finalization checks, and diagnostics.
  • Added on_realtime_text_stabilization_update for applications that need structured realtime stabilization events.

• Docs And Examples

  • Reworked the README into a shorter entry point and moved detailed guidance into docs/.
  • Added docs for installation, configuration, transcription engines, wake words, external audio, FastAPI server usage, troubleshooting, testing, and architecture.
  • Added per-engine documentation for faster-whisper, whisper.cpp, OpenAI Whisper, Moonshine, sherpa-onnx, Parakeet/NeMo, Transformers engines, Cohere, and Kroko-ONNX.

Fixes

• Recorder Stability: Slow Final Transcription

  • Fixed a recorder bug where slow CPU final transcription could cause following speech to be missed while text() was blocked.
  • Completed recordings are now queued, continuous listening stays armed during final transcription, delayed Silero confirmation is tolerated, and finite feed_audio() streams can be flushed.
  • The CPU/int8 regression now preserves all 9/9 utterances with combined WER 0.000.

• Recorder Stability: Stale Pre-Roll Audio

  • Fixed stale pre-recording audio leaking from one utterance into the next final transcription.
  • The pre-roll buffer is now cleared when a recording transitions to stopped, while normal fresh pre-roll behavior is preserved.

• Server Isolation And Backpressure

  • Transcript events are routed only to their owning browser session.
  • Session slots are reserved before recorder construction to prevent connection bursts from over-instantiating recorders.
  • Added per-session backlog limits and long-audio force-finalization to keep the server responsive under load.

Other

• Updated Docker/CUDA packaging to CUDA 12.8.1/cuDNN on Ubuntu 24.04 with PyTorch/Torchaudio 2.7.1 cu128.
• Split GPU Torch requirements into requirements-gpu-torch.txt.
• Updated the legacy browser client WebSocket port from 8001 to 9001.
• Added ignored/excluded local development folders, model caches, test results, private docs/tests, backups, and secrets to .gitignore/MANIFEST.in.
• Added GitHub funding metadata.
• Package version bumped to 1.0.0.

Compatibility Notes

• Existing AudioToTextRecorder usage with the default faster-whisper backend remains the intended compatibility path, but environments should now install the needed extras explicitly, for example pip install "RealtimeSTT[faster-whisper]".
• Some new engines are experimental or platform-sensitive. Kroko-ONNX is registered and contract-tested, but real Windows validation was blocked by upstream native build issues; use Linux, WSL2, or Docker for runtime validation.