Files
hermes-agent/tools/wake_word.py

1109 lines
40 KiB
Python

"""Wake-word ("Hey Hermes") detection — hands-free session trigger.
An always-on hotword listener shared by CLI, TUI and desktop GUI (one owns it,
gated by ``wake_surface_enabled``): on wake Hermes opens a fresh session and
captures voice via the existing pipeline. Engines (openwakeword default,
sherpa open-vocabulary, porcupine premium) are all on-device and live in
:mod:`tools.wake_word_engines`; this module owns config, the capture loop and
the process-wide listener singleton.
Capture reuses voice mode's 16 kHz mono int16 ``sounddevice`` path on a daemon
thread; callers ``pause()`` while a voice turn holds the mic and ``resume()``
once idle (two input streams on one device is unreliable cross-platform).
Nothing here touches agent context or the prompt cache — on wake the caller
gets a plain string, like a transcript.
"""
from __future__ import annotations
import logging
import os
import sys
import threading
import time
from dataclasses import dataclass
from pathlib import Path
from typing import Any, Callable, Dict, Optional
from tools.wake_word_engines import ( # noqa: F401 (re-exported for callers/tests)
_SHERPA_KWS_MODEL_DIR, _SHERPA_KWS_MODEL_URL, _Engine, _OpenWakeWordEngine, _PorcupineEngine,
_SherpaKwsEngine, _ensure_sherpa_model, _looks_like_path, _sherpa_model_root,
)
logger = logging.getLogger(__name__)
# 16 kHz mono int16 — Whisper-native and what every engine expects.
SAMPLE_RATE = 16000
# Minimum gap between two wake fires, so one "hey hermes" can't retrigger
# across several frames while the caller is still reacting.
_FIRE_COOLDOWN_SECONDS = 2.0
_START_TIMEOUT_SECONDS = 5.0
# Ambient-speech rejection: require N consecutive over-threshold frames before
# firing (a stray phoneme spikes one frame; a real phrase holds several).
_DEFAULT_CONFIRMATION_FRAMES = 3
# Dead-mic detection: an int16 stream whose peak stays at/below _SILENCE_PEAK
# for this many consecutive seconds is flagged silent (desktop push-to-talk and
# the backend listener use different capture paths, so one can work while the
# backend-selected stream is all zeros).
_SILENCE_PEAK = 10
_SILENCE_ALERT_SECONDS = 10
# provider alias -> (engine class name on this module, lazy_deps feature).
# Unknown providers probe as openwakeword but fail to build.
_PROVIDERS: Dict[str, tuple[str, str]] = {
"porcupine": ("_PorcupineEngine", "wake.porcupine"),
**{k: ("_SherpaKwsEngine", "wake.sherpa") for k in ("sherpa", "sherpa-onnx", "kws", "open")},
**{k: ("_OpenWakeWordEngine", "wake.openwakeword") for k in ("openwakeword", "oww", "local")},
}
class WakeWordInUse(RuntimeError):
"""Raised when another surface or process owns the wake-word listener."""
# ── Config ──
_DEFAULTS: Dict[str, Any] = {
"enabled": False,
"surface": "auto",
"input_device": None,
# Where PCM is captured: "local" (PortAudio on the backend host),
# "client" (desktop/TUI streams int16 frames via wake.feed), or
# "auto" (local when a device exists, else client capture).
"capture": "auto",
"provider": "openwakeword",
"phrase": "hey hermes",
"sensitivity": 0.6,
"confirmation_frames": _DEFAULT_CONFIRMATION_FRAMES,
"start_new_session": True,
}
# Bundled "hey hermes" model (tools/wakewords/) — the default. Config names in
# _ALIASES resolve to it, not to an openWakeWord built-in.
_BUNDLED_MODEL_NAME = "hey_hermes"
_BUNDLED_MODEL_ALIASES = frozenset({"", "hey_hermes", "hey hermes", "hermes"})
def _bundled_wakeword_path(framework: str = "onnx") -> str:
"""Path to the shipped hey_hermes model (.onnx/.tflite) for ``framework``."""
ext = "tflite" if str(framework).strip().lower() == "tflite" else "onnx"
return os.path.join(os.path.dirname(__file__), "wakewords", f"{_BUNDLED_MODEL_NAME}.{ext}")
def _is_macos_arm64() -> bool:
import platform
return sys.platform == "darwin" and platform.machine() == "arm64"
def default_inference_framework() -> str:
"""tflite on macOS ARM64, onnx elsewhere: openWakeWord's ONNX *embedding*
model scores near-zero on Apple Silicon (upstream #336) — the detector arms
but no phrase ever crosses threshold."""
return "tflite" if _is_macos_arm64() else "onnx"
_warned_onnx_coerced = False
def resolve_inference_framework(cfg: Dict[str, Any]) -> str:
"""Effective openWakeWord backend: explicit ``openwakeword.inference_framework``
or the platform default. The one provably dead combination — explicit
``onnx`` on macOS ARM64 (upstream #336) — is coerced to tflite with a
one-time warning so a pre-fix pin doesn't keep a wake word that never fires.
"""
global _warned_onnx_coerced
sub = cfg.get("openwakeword") if isinstance(cfg.get("openwakeword"), dict) else {}
framework = str(sub.get("inference_framework") or "").strip().lower()
if not framework:
return default_inference_framework()
if framework == "onnx" and _is_macos_arm64():
if not _warned_onnx_coerced:
_warned_onnx_coerced = True
logger.warning(
"wake: openwakeword.inference_framework='onnx' is set but ONNX's "
"embedding model never fires on macOS ARM64 (openWakeWord #336) — "
"using tflite instead. Set inference_framework to '' (auto) or "
"'tflite' in config.yaml to silence this."
)
return "tflite"
return framework
def ensure_tflite_runtime() -> bool:
"""Make ``import tflite_runtime.interpreter`` resolve, returning success.
openWakeWord hardcodes that import but only declares ``tflite-runtime`` on
Linux; on macOS the equivalent wheel is ``ai-edge-litert``. Alias the
module in-process (nothing is written to site-packages).
"""
try:
import tflite_runtime.interpreter # noqa: F401
return True
except ImportError:
pass
try:
from ai_edge_litert import interpreter as _litert # type: ignore[import-not-found]
except ImportError:
return False
import types
pkg = types.ModuleType("tflite_runtime")
pkg.__path__ = [] # type: ignore[attr-defined] # mark as package
sys.modules.setdefault("tflite_runtime", pkg)
sys.modules["tflite_runtime.interpreter"] = _litert
logger.debug("wake word: bridged tflite_runtime -> ai_edge_litert")
return True
def load_wake_word_config() -> Dict[str, Any]:
"""Return the ``wake_word`` config section, shape-guarded to a dict."""
try:
from hermes_cli.config import load_config
cfg = load_config().get("wake_word")
except Exception:
cfg = None
return cfg if isinstance(cfg, dict) else {}
def _get(cfg: Dict[str, Any], key: str) -> Any:
val = cfg.get(key, _DEFAULTS.get(key))
return _DEFAULTS.get(key) if val is None else val
def _clamped(cfg: Dict[str, Any], key: str, cast, lo, hi):
"""Numeric config value via ``cast``, defaulting on junk, clamped to lo..hi."""
try:
n = cast(_get(cfg, key))
except (TypeError, ValueError):
n = cast(_DEFAULTS[key])
return min(max(n, lo), hi)
def _provider(cfg: Dict[str, Any]) -> str:
return str(_get(cfg, "provider")).strip().lower() or "openwakeword"
def _input_device(cfg: Dict[str, Any]) -> int | str | None:
"""Configured PortAudio input selector, preserving indices and names."""
raw = _get(cfg, "input_device")
if raw is None or isinstance(raw, bool):
return None
if isinstance(raw, int):
return raw
return str(raw).strip() or None
def _sensitivity(cfg: Dict[str, Any]) -> float:
return _clamped(cfg, "sensitivity", float, 0.0, 1.0)
def _confirmation_frames(cfg: Dict[str, Any]) -> int:
"""Consecutive over-threshold frames required to fire, clamped 1..10.
``1`` restores single-frame behaviour; higher rejects ambient blips at the
cost of a few tens of ms of latency.
"""
return _clamped(cfg, "confirmation_frames", int, 1, 10)
def wake_phrase(cfg: Optional[Dict[str, Any]] = None) -> str:
"""Human-facing wake phrase label (purely cosmetic; engine keys detection)."""
cfg = cfg if cfg is not None else load_wake_word_config()
return str(_get(cfg, "phrase")) or "hey hermes"
def resolve_capture_mode(
cfg: Optional[Dict[str, Any]] = None,
*,
prefer_client: bool = False,
force_local: bool = False,
) -> str:
"""Return ``local`` or ``client`` capture mode for this arm.
``prefer_client`` is set by remote desktop; ``force_local`` keeps CLI/TUI on
the process mic. Under ``auto`` a working backend input always wins (local
desktops keep PortAudio + ``input_device``); client is the fallback only for
a preferring surface with no usable backend mic — CLI/TUI stay local so
status reports the real requirement rather than a path nothing will feed.
"""
cfg = cfg if cfg is not None else load_wake_word_config()
if force_local:
return "local"
raw = str(_get(cfg, "capture") or "auto").strip().lower()
if raw in ("client", "remote", "external"):
return "client"
if raw == "local":
return "local"
if prefer_client and not _local_input_device_ready():
return "client"
return "local"
def _input_channels(info: Any) -> int:
channels = info.get("max_input_channels") if isinstance(info, dict) else None
if channels is None:
channels = getattr(info, "max_input_channels", 0)
return int(channels or 0)
def _local_input_device_ready() -> bool:
"""True when PortAudio is importable and at least one input device exists."""
try:
sd, _ = _import_audio()
except (ImportError, OSError):
return False
try:
devices = sd.query_devices()
if isinstance(devices, dict):
return _input_channels(devices) > 0
if any(_input_channels(dev) > 0 for dev in devices):
return True
# Also accept a resolvable default input (some hosts list devices oddly).
return _input_channels(sd.query_devices(None, "input")) > 0
except Exception:
return False
def wake_surface_enabled(surface: str, cfg: Optional[Dict[str, Any]] = None) -> bool:
"""Should ``surface`` (``cli`` / ``tui`` / ``gui``) host the listener?
True when enabled and the configured ``surface`` is ``auto`` or this exact
surface. ``auto`` only makes a surface eligible; the process/machine
ownership lock still permits a single claimant.
"""
cfg = cfg if cfg is not None else load_wake_word_config()
if not cfg.get("enabled"):
return False
want = str(_get(cfg, "surface")).strip().lower() or "auto"
return want == "auto" or want == surface.strip().lower()
# ── Multi-profile phrase enrollment (open-vocabulary routing) ──
def _active_profile_name() -> str:
try:
from hermes_cli.profiles import get_active_profile_name
return get_active_profile_name() or "default"
except Exception:
return "default"
def enrolled_profile_phrases() -> Dict[str, str]:
"""Map ``profile name -> wake phrase`` for every wake-enabled profile.
Reads each profile's own ``config.yaml`` raw (``load_config()`` targets only
the ACTIVE profile). Enrolled = ``wake_word.enabled`` truthy; phrase defaults
to ``"hey <profile>"``. The sherpa engine listens for all of them at once and
routes the wake to the matching profile. Best-effort: unreadable skipped.
"""
phrases: Dict[str, str] = {}
try:
from hermes_cli.config import read_user_config_raw
from hermes_cli.profiles import get_profile_dir, list_profiles
for info in list_profiles():
name = getattr(info, "name", None) or str(info)
try:
raw = read_user_config_raw(Path(get_profile_dir(name)) / "config.yaml")
wc = raw.get("wake_word") or {}
if not isinstance(wc, dict) or not wc.get("enabled"):
continue
phrase = str(wc.get("phrase") or f"hey {name}").strip()
if phrase:
phrases[name] = phrase
except Exception:
continue
except Exception:
pass
return phrases
# ── Audio capture (lazy — never import sounddevice at module load) ──
def _import_audio():
import numpy as np
import sounddevice as sd
return sd, np
def _audio_available() -> bool:
try:
_import_audio()
return True
except (ImportError, OSError):
return False
def _describe_input_device(sd, selector: int | str | None) -> Dict[str, Any]:
"""Resolve a PortAudio selector into JSON-safe diagnostics.
Diagnostic only: ``InputStream`` remains the authority on whether the
device can actually open at the requested format.
"""
details: Dict[str, Any] = {"selector": selector}
try:
info = sd.query_devices(selector, "input")
except Exception as e:
details["error"] = str(e)
return details
if not isinstance(info, dict):
return details
if info.get("name"):
details["name"] = str(info["name"])
for key, out_key, cast in (
("max_input_channels", "max_input_channels", int),
("default_samplerate", "default_samplerate", float),
("hostapi", "hostapi_index", int),
):
if isinstance(info.get(key), (int, float)):
details[out_key] = cast(info[key])
if "hostapi_index" in details:
try:
hostapi = sd.query_hostapis(details["hostapi_index"])
hostapi_name = hostapi.get("name") if isinstance(hostapi, dict) else None
if hostapi_name:
details["hostapi"] = str(hostapi_name)
except Exception:
pass
return details
def _device_label(details: Dict[str, Any]) -> str:
name = str(details.get("name") or "").strip()
selector = details.get("selector")
label = name or ("system default" if selector is None else str(selector))
hostapi = str(details.get("hostapi") or "").strip()
return f"{label} ({hostapi})" if hostapi else label
def _capture_sample_rate(details: Dict[str, Any]) -> int:
"""Use the selected device's native rate when PortAudio reports one."""
rate = details.get("default_samplerate")
if isinstance(rate, (int, float)) and not isinstance(rate, bool) and rate > 0:
try:
return int(round(rate))
except (OverflowError, ValueError):
pass
return SAMPLE_RATE
def _resample_audio_frame(np, frame, output_length: int):
"""Convert one native-rate capture block to an exact engine frame."""
source = np.asarray(frame, dtype=np.float64).reshape(-1)
if source.size == output_length:
return np.asarray(frame, dtype=np.int16).reshape(-1)
if source.size == 0:
return np.zeros(output_length, dtype=np.int16)
if source.size > output_length:
# Average each source window when reducing (matches the desktop wake
# capture path) so speech energy is retained instead of decimated.
edges = np.linspace(0, source.size, output_length + 1, dtype=np.int64)
values = np.add.reduceat(source, edges[:-1]) / np.diff(edges)
else:
# Unusual low-rate devices: interpolate up to the 16 kHz frame size.
source_positions = np.arange(source.size, dtype=np.float64)
target_positions = np.linspace(0, source.size - 1, output_length)
values = np.interp(target_positions, source_positions, source)
return np.rint(values).clip(-32768, 32767).astype(np.int16)
def silent_audio_hint(details: Dict[str, Any]) -> str:
"""Platform-specific remediation for an armed stream delivering silence."""
if sys.platform == "darwin":
return (
"Microphone delivers only silence. Grant the Hermes backend "
"microphone access in System Settings > Privacy & Security > "
"Microphone, then toggle the wake word."
)
if sys.platform == "win32":
return (
f"Microphone delivers only silence from {_device_label(details)}. "
"Set wake_word.input_device to a different PortAudio input device, "
"then toggle the wake word."
)
return (
f"Microphone delivers only silence from {_device_label(details)}. "
"Check the selected input device, then toggle the wake word."
)
# ── Engines (implementations live in tools.wake_word_engines) ──
def _build_engine(cfg: Dict[str, Any]) -> _Engine:
provider = _provider(cfg)
if provider not in _PROVIDERS:
raise ValueError(f"Unknown wake_word provider: {provider!r}")
return globals()[_PROVIDERS[provider][0]](cfg)
# ── Requirements probe (for /wake status + enable path) ──
def _stt_ready() -> bool:
"""Is a speech-to-text provider configured and enabled?
A wake without STT arms the mic but every utterance dies at transcription.
Same standard as voice mode's ``check_voice_requirements``.
"""
try:
from tools.transcription_tools import _get_provider, _load_stt_config, is_stt_enabled
stt_config = _load_stt_config()
return is_stt_enabled(stt_config) and _get_provider(stt_config) != "none"
except Exception:
return False
_LAZY_TTS_FEATURES = {"edge": "tts.edge", "elevenlabs": "tts.elevenlabs", "mistral": "tts.mistral"}
def _tts_ready() -> bool:
"""Can the configured TTS provider run (or install at first use)?
PROBE, not an installer: ``check_tts_requirements`` lazily pip-installs the
provider SDK, which froze wake.status polls for a whole pip run (a failed
install unmounted the desktop ear). Uninstalled deps count as ready iff
lazy installs are allowed; pip is never touched from here.
"""
try:
from tools.tts_tool import _get_provider, _load_tts_config
provider = _get_provider(_load_tts_config())
except Exception:
return False
feature = _LAZY_TTS_FEATURES.get(provider)
if feature is not None:
try:
from tools import lazy_deps
if not lazy_deps.is_available(feature):
return lazy_deps._allow_lazy_installs()
except Exception:
return False
try:
from tools.tts_tool import check_tts_requirements
return bool(check_tts_requirements())
except Exception:
return False
def check_wake_word_requirements(cfg: Optional[Dict[str, Any]] = None) -> Dict[str, Any]:
"""Report whether wake-word detection can run, with a remediation hint."""
cfg = cfg if cfg is not None else load_wake_word_config()
provider = _provider(cfg)
from tools import lazy_deps
feature = _PROVIDERS.get(provider, ("", "wake.openwakeword"))[1]
deps_ok = lazy_deps.is_available(feature)
lazy_ok = lazy_deps._allow_lazy_installs()
# The audio probe imports sounddevice + numpy — packages the lazy installer
# would fetch — so only trust it once deps are installed; on a fresh install
# the engine constructors' ``lazy_deps.ensure()`` + stream-open surface any
# real audio problem (gating on the probe made lazy install unreachable).
audio_ok = _audio_available() if deps_ok else False
key_ok = True
# Loop is wake → record → STT → agent → TTS; without either end the mic
# hears you and nothing perceptible happens — refuse with a hint.
stt_ok = _stt_ready()
tts_ok = _tts_ready()
hint = ""
# tflite needs a runtime openWakeWord doesn't declare off Linux; report it
# as a remediation instead of arming a detector that can't fire.
tflite_ok = True
if feature == "wake.openwakeword" and resolve_inference_framework(cfg) == "tflite":
tflite_ok = ensure_tflite_runtime() or lazy_deps.is_available("wake.openwakeword.tflite") or lazy_ok
if provider == "porcupine" and not (os.getenv("PORCUPINE_ACCESS_KEY") or "").strip():
key_ok = False
hint = "Set PORCUPINE_ACCESS_KEY (free key at https://console.picovoice.ai)."
elif not deps_ok and not lazy_ok:
hint = lazy_deps.feature_install_command(feature) or ""
elif not tflite_ok:
hint = "The wake word needs the tflite runtime on this Mac: pip install ai-edge-litert"
elif deps_ok and not audio_ok and resolve_capture_mode(cfg) == "local":
hint = "Microphone capture needs sounddevice + numpy and a working audio device."
elif not stt_ok or not tts_ok:
missing = " and ".join(
name for name, ok in (("speech-to-text", stt_ok), ("text-to-speech", tts_ok)) if not ok
)
hint = (f"Wake word needs {missing} configured — run `hermes tools` "
f"(Voice section) or see the voice-mode docs.")
capture_mode = resolve_capture_mode(cfg)
# Client capture needs deps (engine) but not a server-side PortAudio device.
if capture_mode == "client":
mic_ok = deps_ok or lazy_ok
else:
mic_ok = (deps_ok and audio_ok) or (not deps_ok and lazy_ok)
if deps_ok and not audio_ok and not hint:
hint = (
"No local microphone on this backend. Remote desktop can stream "
"the client mic — set wake_word.capture: client or use a desktop "
"build with client-capture wake support."
)
return {
"available": key_ok and stt_ok and tts_ok and tflite_ok and mic_ok,
"provider": provider,
"deps_available": deps_ok,
"audio_available": audio_ok,
"local_input_available": _local_input_device_ready() if deps_ok else False,
"capture": capture_mode,
"access_key_set": key_ok,
"stt_available": stt_ok,
"tts_available": tts_ok,
"phrase": wake_phrase(cfg),
"hint": hint,
}
# ── Detector ──
@dataclass
class _Capture:
"""One armed audio source: a PortAudio stream (local) or the feed queue (client)."""
stream: Any = None # sounddevice.InputStream, None in client mode
queue: Any = None # client-capture frame queue, None in local mode
np: Any = None
rate: int = SAMPLE_RATE
frame_length: int = 1280 # samples per read at ``rate``
def read(self):
"""One raw block; None when no client frame arrived within 250 ms.
Stream errors propagate."""
if self.stream is not None:
return self.stream.read(self.frame_length)[0]
try:
return self.queue.get(timeout=0.25)
except Exception:
return None
def close(self) -> None:
try:
if self.stream is not None:
self.stream.stop()
self.stream.close()
except Exception:
pass
class WakeWordDetector:
"""Background hotword listener. Fires ``on_wake()`` when the phrase is heard.
The engine is built once and kept alive across pause/resume; only the audio
stream + reader thread cycle, so toggling the mic for a voice turn is cheap.
"""
def __init__(self, engine: _Engine, on_wake: Callable[[], None],
cooldown: float = _FIRE_COOLDOWN_SECONDS,
on_failure: Optional[Callable[["WakeWordDetector"], None]] = None,
input_device: int | str | None = None,
external_audio: bool = False):
self.engine = engine
self.on_wake = on_wake
self.cooldown = cooldown
self.on_failure = on_failure
self.input_device = input_device
self.external_audio = bool(external_audio)
self.input_device_details: Dict[str, Any] = (
{"selector": "client", "name": "client capture", "hostapi": "remote"}
if self.external_audio
else {"selector": input_device}
)
self._thread: Optional[threading.Thread] = None
self._stop = threading.Event()
self._callback_inflight = threading.Event()
self._last_fire = 0.0
self._lock = threading.Lock()
# Client-capture PCM queue (int16 mono frames). Local mode ignores this.
import queue as _queue
self._audio_q: "_queue.Queue[Any]" = _queue.Queue(maxsize=64)
# True when the stream is open but every frame is (near-)silence, so
# status surfaces can tell "armed" from "deaf".
self.audio_silent = False
self._silent_frames = 0
@property
def running(self) -> bool:
t = self._thread
return t is not None and t.is_alive()
def feed(self, pcm_int16) -> None:
"""Enqueue one int16 mono frame (or raw bytes) for client capture.
Short frames are zero-padded to ``engine.frame_length``; long frames are
split. On queue overflow the oldest frame is dropped to stay real-time.
"""
if not self.external_audio:
return
try:
import numpy as np
except Exception:
return
if isinstance(pcm_int16, (bytes, bytearray, memoryview)):
arr = np.frombuffer(pcm_int16, dtype=np.int16)
else:
arr = np.asarray(pcm_int16, dtype=np.int16).reshape(-1)
fl = int(self.engine.frame_length)
if fl <= 0:
return
for offset in range(0, int(arr.shape[0]), fl):
chunk = arr[offset : offset + fl]
if chunk.shape[0] < fl:
pad = np.zeros(fl, dtype=np.int16)
pad[: chunk.shape[0]] = chunk
chunk = pad
try:
self._audio_q.put_nowait(chunk)
except Exception:
try: # full: drop the oldest frame, then retry once
self._audio_q.get_nowait()
self._audio_q.put_nowait(chunk)
except Exception:
pass
def start(self) -> None:
"""Open the mic (or client feeder) and begin listening. Idempotent."""
with self._lock:
if self._thread is not None and self._thread.is_alive():
return
self._stop.clear()
ready = threading.Event()
startup_errors: list[BaseException] = []
self._thread = threading.Thread(
target=self._run,
args=(ready, startup_errors),
daemon=True,
name="wake-word",
)
self._thread.start()
if not ready.wait(_START_TIMEOUT_SECONDS):
self._halt_thread()
raise TimeoutError("Timed out while opening the wake-word microphone.")
if startup_errors:
self._halt_thread()
raise RuntimeError("Failed to open the wake-word microphone.") from startup_errors[0]
# pause/resume keep the engine; stop tears it down.
def pause(self) -> None:
self._halt_thread()
def resume(self) -> None:
self.start()
def stop(self) -> None:
self._halt_thread()
self.engine.close()
def _halt_thread(self) -> None:
with self._lock:
self._stop.set()
t = self._thread
if t is not None and t is not threading.current_thread():
t.join(timeout=2.0)
if self._thread is t:
self._thread = None
def _dispatch_wake(self) -> None:
try:
self.on_wake()
except Exception as e:
logger.warning("wake word callback failed: %s", e)
finally:
self._callback_inflight.clear()
def _open_capture(self, frame_length: int) -> _Capture:
"""Open the audio source; raises on any local-mic failure."""
if self.external_audio:
# Drain any stale frames from a previous arm.
try:
while True:
self._audio_q.get_nowait()
except Exception:
pass
logger.info(
"wake word: client-capture mode (frame=%d, rate=%d) — waiting for wake.feed",
frame_length, SAMPLE_RATE,
)
return _Capture(queue=self._audio_q, frame_length=frame_length)
try:
sd, np = _import_audio()
except (ImportError, OSError) as e:
logger.error("wake word: audio libraries unavailable: %s", e)
raise
self.input_device_details = _describe_input_device(sd, self.input_device)
cap = _Capture(np=np, rate=_capture_sample_rate(self.input_device_details))
cap.frame_length = max(1, int(round(frame_length * cap.rate / SAMPLE_RATE)))
logger.info(
"wake word: opening microphone device=%s selector=%r hostapi=%s "
"default_rate=%s capture_rate=%d engine_rate=%d",
self.input_device_details.get("name") or "system default",
self.input_device,
self.input_device_details.get("hostapi") or "unknown",
self.input_device_details.get("default_samplerate") or "unknown",
cap.rate,
SAMPLE_RATE,
)
try:
cap.stream = sd.InputStream(
device=self.input_device,
samplerate=cap.rate,
channels=1,
dtype="int16",
blocksize=cap.frame_length,
)
cap.stream.start()
except Exception as e:
logger.error("wake word: failed to open microphone: %s", e)
raise
return cap
def _note_silence(self, frame, silent_alert_frames: int) -> None:
"""Track consecutive near-zero frames; flag/unflag ``audio_silent``."""
try:
peak = int(abs(frame).max()) if len(frame) else 0
except Exception:
peak = _SILENCE_PEAK + 1
if peak <= _SILENCE_PEAK:
self._silent_frames += 1
if self._silent_frames == silent_alert_frames:
self.audio_silent = True
logger.warning(
"wake word: mic delivers only silence (peak<=%d for %ds); %s",
_SILENCE_PEAK, _SILENCE_ALERT_SECONDS,
silent_audio_hint(self.input_device_details),
)
elif self._silent_frames:
if self.audio_silent:
logger.info("wake word: mic audio detected — stream healthy")
self._silent_frames = 0
self.audio_silent = False
def _fire(self) -> None:
"""Honor the cooldown, then run ``on_wake`` on its own thread (once)."""
now = time.monotonic()
if now - self._last_fire < self.cooldown:
logger.debug("wake word: detection within cooldown — ignored")
return
self._last_fire = now
logger.info("wake word: phrase detected — firing callback")
if not self._callback_inflight.is_set():
self._callback_inflight.set()
threading.Thread(target=self._dispatch_wake, daemon=True, name="wake-word-callback").start()
def _run(self, ready: threading.Event,
startup_errors: list[BaseException]) -> None:
frame_length = self.engine.frame_length
try:
cap = self._open_capture(frame_length)
except Exception as e:
startup_errors.append(e)
ready.set()
return
# Drop buffered audio/feature state so a resume right after a voice turn
# can't re-fire on audio captured before the pause (the wake → voice →
# resume → wake runaway loop).
try:
self.engine.reset()
except Exception:
pass
logger.info("wake word: listening (frame=%d, rate=%d, external=%s)",
frame_length, SAMPLE_RATE, self.external_audio)
ready.set()
failed = False
silent_alert_frames = max(1, int(_SILENCE_ALERT_SECONDS * SAMPLE_RATE / max(1, frame_length)))
try:
while not self._stop.is_set():
try:
data = cap.read()
except Exception as e:
logger.warning("wake word: stream read error: %s", e)
failed = not self._stop.is_set()
break
if data is None:
# No client frames yet — count as silence for status.
self._silent_frames += 1
if self._silent_frames == silent_alert_frames:
self.audio_silent = True
continue
frame = data[:, 0] if getattr(data, "ndim", 1) == 2 else data
if cap.rate != SAMPLE_RATE:
frame = _resample_audio_frame(cap.np, frame, frame_length)
self._note_silence(frame, silent_alert_frames)
try:
fired = self.engine.process(frame)
except Exception as e:
logger.debug("wake word: engine error: %s", e)
continue
if fired:
self._fire()
finally:
cap.close()
logger.info("wake word: stream closed")
if failed and self.on_failure is not None:
self.on_failure(self)
# ── Process-wide singleton (mirrors hermes_cli.voice's continuous API) ──
_detector: Optional[WakeWordDetector] = None
_detector_owner: object | None = None
_detector_file_lock = None
_detector_lock = threading.Lock()
def _lock_path() -> Path:
from hermes_constants import get_default_hermes_root
return get_default_hermes_root() / "runtime" / "wake-word.lock"
def _flock(handle, acquire: bool) -> None:
"""Non-blocking exclusive lock (or unlock) of one byte / whole file, per OS."""
if os.name == "nt":
import msvcrt
if acquire: # msvcrt needs at least one byte to lock
handle.seek(0, os.SEEK_END)
if handle.tell() == 0:
handle.write(b"\0")
handle.flush()
handle.seek(0)
msvcrt.locking(handle.fileno(), msvcrt.LK_NBLCK if acquire else msvcrt.LK_UNLCK, 1)
else:
import fcntl
fcntl.flock(handle.fileno(), (fcntl.LOCK_EX | fcntl.LOCK_NB) if acquire else fcntl.LOCK_UN)
def _acquire_machine_lock(path: Optional[Path] = None):
"""Acquire the cross-process microphone lease, or raise WakeWordInUse."""
lock_path = path or _lock_path()
lock_path.parent.mkdir(parents=True, exist_ok=True)
handle = open(lock_path, "a+b")
try:
_flock(handle, True)
except (OSError, BlockingIOError) as e:
handle.close()
raise WakeWordInUse("Wake-word microphone is already owned.") from e
return handle
def _release_machine_lock(handle) -> None:
if handle is None:
return
try:
_flock(handle, False)
except OSError:
pass
finally:
handle.close()
def _clear_singleton_locked() -> tuple[Optional[WakeWordDetector], Any]:
"""Forget the armed detector (caller holds ``_detector_lock``); returns (detector, lock handle)."""
global _detector, _detector_owner, _detector_file_lock
det, handle = _detector, _detector_file_lock
_detector = None
_detector_owner = None
_detector_file_lock = None
return det, handle
def _owned_detector(owner: object) -> Optional[WakeWordDetector]:
"""The armed detector iff ``owner`` holds the lease (caller holds the lock)."""
return _detector if _detector is not None and _detector_owner is owner else None
def _detector_failed(detector: WakeWordDetector) -> None:
"""Release ownership if the active microphone stream dies unexpectedly."""
with _detector_lock:
if _detector is not detector:
return
_, lock_handle = _clear_singleton_locked()
try:
detector.engine.close()
finally:
_release_machine_lock(lock_handle)
def start_listening(
on_wake: Callable[[], None],
*,
owner: object,
config: Optional[Dict[str, Any]] = None,
external_audio: bool = False,
) -> WakeWordDetector:
"""Claim, build, and start the detector. Idempotent for the same owner.
Raises if engine construction fails (missing deps / access key / model);
callers should probe :func:`check_wake_word_requirements` first. A different
owner, including another process, receives :class:`WakeWordInUse`.
"""
if owner is None:
raise ValueError("wake-word owner must not be None")
global _detector, _detector_owner, _detector_file_lock
with _detector_lock:
if _detector is not None:
if _detector_owner is not owner:
raise WakeWordInUse("Wake-word microphone is already owned.")
_detector.on_wake = on_wake
_detector.resume()
return _detector
lock_handle = _acquire_machine_lock()
try:
cfg = config if config is not None else load_wake_word_config()
engine = _build_engine(cfg)
detector = WakeWordDetector(
engine,
on_wake,
on_failure=_detector_failed,
input_device=_input_device(cfg),
external_audio=external_audio,
)
_detector = detector
_detector_owner = owner
_detector_file_lock = lock_handle
detector.start()
return detector
except Exception:
det, _ = _clear_singleton_locked()
try:
if det is not None:
det.stop()
except Exception:
pass
_release_machine_lock(lock_handle)
raise
def owns_listener(owner: object) -> bool:
with _detector_lock:
return _owned_detector(owner) is not None
def _owned_call(owner: object, method: str) -> bool:
with _detector_lock:
det = _owned_detector(owner)
if det is None:
return False
getattr(det, method)()
return True
def pause_listening(*, owner: object) -> bool:
"""Release the microphone only when ``owner`` holds the lease."""
return _owned_call(owner, "pause")
def resume_listening(*, owner: object) -> bool:
"""Re-open the microphone only when ``owner`` holds the lease."""
return _owned_call(owner, "resume")
def stop_listening(*, owner: object) -> bool:
"""Fully stop the detector only when ``owner`` holds the lease."""
with _detector_lock:
if _owned_detector(owner) is None:
return False
det, lock_handle = _clear_singleton_locked()
try:
det.stop()
finally:
_release_machine_lock(lock_handle)
return True
def _current_detector() -> Optional[WakeWordDetector]:
with _detector_lock:
return _detector
def is_listening() -> bool:
det = _current_detector()
return det is not None and det.running
def audio_is_silent() -> bool:
"""True when the armed stream has delivered only silence (dead mic).
The stream opens fine but every frame is zeros, so detection can never
fire; status surfaces show "listening but the microphone appears silent".
"""
det = _current_detector()
return det is not None and det.audio_silent
def get_input_device_status(cfg: Optional[Dict[str, Any]] = None) -> Dict[str, Any]:
"""Return configured/active PortAudio input diagnostics for status UIs."""
det = _current_detector()
if det is not None:
return dict(det.input_device_details)
cfg = cfg if cfg is not None else load_wake_word_config()
selector = _input_device(cfg)
try:
sd, _ = _import_audio()
except (ImportError, OSError) as e:
return {"selector": selector, "error": str(e)}
return _describe_input_device(sd, selector)
def get_last_match() -> Optional[tuple[str, str]]:
"""(matched phrase, profile) of the most recent wake fire, if the engine
reports per-phrase matches (sherpa multi-profile routing). None otherwise."""
det = _current_detector()
return None if det is None else getattr(det.engine, "last_match", None)
def feed_audio(*, owner: object, pcm_int16) -> bool:
"""Push client-captured PCM into the armed detector (client capture mode).
Returns True when the frame was accepted for ``owner``'s armed detector.
"""
with _detector_lock:
det = _owned_detector(owner)
if det is None or not det.external_audio:
return False
det.feed(pcm_int16)
return True
def detector_frame_info() -> Dict[str, Any]:
"""Sample rate + frame length for client capture streamers."""
det = _current_detector()
if det is None:
return {"sample_rate": SAMPLE_RATE, "frame_length": 1280}
return {
"sample_rate": SAMPLE_RATE,
"frame_length": int(getattr(det.engine, "frame_length", 1280) or 1280),
"external_audio": bool(det.external_audio),
}