Kokoro has been stale upstream since April 2025 (`requires_python<3.13`),
which broke the Python 3.14 build. Piper is the active replacement:
maintained by OHF/Home Assistant, depends only on onnxruntime +
pathvalidate (no torch, no spacy, no transformers), and has cp314
support today.
Dockerfile:
- Add `pip install piper-tts` after the STT install.
- Bundle two default voices (en_US-amy-medium, en_US-ryan-medium) into
/opt/piper-voices at build. Additional voices can be downloaded into
/data/voices via the admin UI (separate commit).
- Image add over the STT-only baseline: ~150 MB.
services/tts.py — full rewrite:
- New voice-discovery layer scans /opt/piper-voices + /data/voices for
.onnx + .onnx.json pairs. /data wins over /opt for the same id so
admin-downloaded voices can override bundled defaults.
- Single PiperVoice kept warm; switches via _switch_voice() when the
user changes their voice_tts_voice setting.
- list_voices() returns metadata read from .onnx.json sidecars (label
derived from filename, language, quality, sample_rate).
- synthesise() uses piper's SynthesisConfig; converts kokoro-shaped
`speed` multiplier to piper's `length_scale` (1.0 / speed).
- `voice_blend` parameter accepted but ignored — piper has no blend
equivalent; first entry's voice is used if anything is passed.
- Dropped: HuggingFace commit-hash tracking (~80 lines), the daily
check_for_kokoro_updates task, voice-tensor blending math.
routes/voice.py:
- tts_backend reports "piper" in /api/voice/status.
- /api/voice/voices no longer requires tts_available() — even with
the active voice failed to load, the catalog still lets the user
pick a different one.
- Synthesise request body dropped the voice_blend field; speed and
voice still supported.
alembic 0047_reset_voice_tts_settings:
- Deletes any stored voice_tts_voice (kokoro IDs that don't map to
piper) and voice_tts_blend (no piper equivalent) rows. Both
re-default cleanly on next read.
frontend:
- VoiceBlendEntry type removed from api/client.ts.
- synthesiseSpeech() signature dropped the voiceBlend parameter.
- SettingsView.vue Voice Blend section removed entirely (slider,
preview, slot management). voice_tts_blend save path removed.
- Default voice id changed from "af_heart" to "en_US-amy-medium".
- VoiceEntry gains optional language/quality/sample_rate fields
from the richer piper sidecar metadata.
Voice paths remain lazily guarded — `VOICE_ENABLED=false` (default)
starts the app cleanly regardless of which TTS deps are present.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
