# CosyVoice

Multilingual expressive TTS with zero-shot voice cloning, served by
the `neosun/cosyvoice` wrapper around FunAudioLLM's
Fun-CosyVoice3-0.5B-2512.

**Server:** irv-ml1 (Irvine, WireGuard-only)
**Port:** 8190 (configurable via `.env`; container listens on 8188
internally but host port moved to avoid ComfyUI's 8188)
**GPUs:** both exposed (`NVIDIA_VISIBLE_DEVICES=all`); image reads
`CUDA_VISIBLE_DEVICES` for pinning
**Upstream wrapper:** [neosun100/cosyvoice-docker](https://github.com/neosun100/cosyvoice-docker)
**Upstream model:** [FunAudioLLM/Fun-CosyVoice3-0.5B-2512](https://huggingface.co/FunAudioLLM/Fun-CosyVoice3-0.5B-2512)

## Why CosyVoice 3 (and not Kokoro / v2)

Emotive content was the deal-breaker for Kokoro. CosyVoice 3 extended
the v2 instruction-following dataset from 1,500 → 5,000 hours
specifically covering emotions, speed, tones, dialects, accents, and
role-playing. Streaming is available on `/api/tts` at ~150 ms TTFB
(not on the OpenAI-compat `/v1/audio/speech` path — see API table
below).

Language center of gravity is Mandarin + Cantonese (18+ Chinese
dialects) and then 8 other languages (English, Japanese, Korean,
German, Spanish, French, Italian, Russian). English works fine but
don't expect ElevenLabs-grade English prosody polish — ear-test with
your actual content.

## API endpoints

| Method + path | Purpose | Streaming? |
|---|---|---|
| `POST /v1/voices/create` | Clone a speaker from reference audio | n/a |
| `GET /v1/voices` | List cloned voices | n/a |
| `GET /v1/voices/{voice_id}` | Inspect one voice | n/a |
| `DELETE /v1/voices/{voice_id}` | Remove a cloned voice | n/a |
| `GET /v1/models` | Lists `cosyvoice-v3` + `cosyvoice-v2` (both bundled) | n/a |
| `POST /v1/audio/speech` | OpenAI drop-in TTS | **no** — single response body |
| `POST /api/tts` | Native TTS with finer control | **yes** when `stream=true` |
| `POST /api/tts/async` | Job-based TTS; poll `/api/task/{task_id}` | no |
| `GET /health` | Health probe | n/a |
| Web UI at `/` | Gradio-style voice-cloning + inference UI | — |

Notably **not** exposed:
- No `preset_voices` / `spk_id` — `/api/speakers` always returns `[]`
  in this image. CosyVoice's built-in SFT speakers (中文男/女 etc.) are
  not surfaced. Every synthesis needs a voice that came from
  `/v1/voices/create`.
- No WebSocket / SSE endpoints — the upstream CosyVoice 3 model
  supports bi-directional streaming at ~150 ms TTFB, but this wrapper
  doesn't surface WS. Use `/api/tts` with `stream=true` for HTTP
  chunked streaming (still ~150 ms TTFB).

## Path layout

| Host path | Container path | Purpose | Restic? |
|---|---|---|---|
| `/worktank/cosyvoice/voices/` | `/data/voices` | Cloned speaker profiles | **included** (precious — reproducing a clone needs the original reference audio) |
| `/worktank/cosyvoice/input/` | `/data/input` | Scratch for uploaded source audio | excluded |
| `/worktank/cosyvoice/output/` | `/data/output` | Synthesized clips | excluded (regenerable) |

**Model weights (~2–3 GB) are NOT bind-mounted.** The image places
them at `pretrained_models/Fun-CosyVoice3-0.5B/` inside the container
on first run. Docker's image-layer cache keeps them across normal
`compose up -d` recreates; a `docker image rm` or tag bump re-downloads.

## First-time deploy on irv-ml1

```bash
# 1. Push compose + env template
scripts/deploy-stack.sh irv-ml1 cosyvoice

# 2. Create the host dirs. One-time sudo — /worktank is root-owned.
ssh -t irv-ml1 'sudo mkdir -p /worktank/cosyvoice/{voices,input,output} && \
                sudo chown -R lkraven:lkraven /worktank/cosyvoice'

# 3. Pull + up. First `up` downloads ~2–3 GB of model weights inside
#    the container; allow a few minutes before the health probe passes.
ssh irv-ml1 '
  cd /opt/docker/compose/cosyvoice && \
  cp -n .env.example .env && \
  docker compose config >/dev/null && \
  docker compose pull && \
  docker compose up -d && \
  docker compose logs -f --tail=30
'
```

## Gotchas (read before first use)

- **No default voice ships with the image.** You must clone one via
  `/v1/voices/create` before `/v1/audio/speech` can return audio.
  Calling `/v1/audio/speech` with `voice="default"` (or any
  unregistered id) returns HTTP 400; curl writing the error JSON into
  a `.wav` file is what the 124-byte phantom output was in an early
  smoke test.
- **Reference audio must be ≤ 30 seconds.** The frontend asserts
  `speech.shape[1] / 16000 <= 30` — longer clips are accepted at
  upload time but synthesis raises `AssertionError: do not support
  extract speech token for audio longer than 30s`, producing a 500.
  Trim with ffmpeg before `/v1/voices/create`:
  `ffmpeg -i src.wav -ss 0 -t 25 -ac 1 -ar 16000 ref.wav`
- **Provide an accurate transcript with the clone.** The `text` field
  of `/v1/voices/create` defaults to empty, in which case the wrapper
  auto-transcribes via Fun-ASR-Nano. That often misses names /
  technical terms. Supplying your own transcript (e.g., from the
  Parakeet stack at `:8765`) produces better clones.
- **Voice id vs. name.** The response's `voice_id` is what you pass
  to subsequent `/v1/audio/speech` calls. The `name` is purely for
  humans — reusing a name with a new upload creates a **new** voice
  id, it doesn't overwrite.
- **Model choice.** `cosyvoice-v3` is default and best; `cosyvoice-v2`
  is available as a fallback if you have voices tuned against the
  v2 model's idiosyncrasies.
- **The `instruct` field is Chinese-context-only — DON'T use it
  for English emotion control.** Verified empirically 2026-04-24:
  any value in `instruct` (English, Chinese, or empty hints inside
  it) routes through CosyVoice's `inference_instruct2` which expects
  a directive in the upstream Chinese template
  (`You are a helpful assistant. <directive>请用…<|endofprompt|>`).
  English values like `instruct: "speak with cold contempt"` cause
  the model to *vocalize the instruction text itself* — you'll hear
  Chinese-flavored phonemes reading the English directive instead
  of your `input`. Workaround: **use the XML inline tags** (`<angry>`,
  `<sad>`, `<surprised>`, `<fearful>`, `<fast>`, `<slow>`,
  `<whisper>`, `<shout>`, `<peppa>`, `<robot>`) for English emotion
  control. They're parsed as control tokens, not content. See
  upstream issue [reference TBD].

## Smoke test (full clone → synthesize)

```bash
# 1. Trim reference audio to ≤30s (16 kHz mono is cleanest input)
ffmpeg -i glados.wav -ss 0 -t 25 -ac 1 -ar 16000 glados_25s.wav

# 2. Transcribe the trimmed clip via Parakeet for an accurate text field
curl -s -F "file=@./glados_25s.wav" http://10.100.79.3:8765/transcribe \
  | tee glados_25s.txt

# 3. Clone the voice
curl -X POST http://10.100.79.3:8190/v1/voices/create \
  -F "audio=@./glados_25s.wav" \
  -F "name=glados" \
  -F "text=<paste from glados_25s.txt>"
# → {"voice_id": "<id>", "name": "glados", ...}

# 4. Synthesize via OpenAI-compat endpoint (single-shot).
#    For English emotion control, use the XML inline tag — NOT the
#    `instruct` field (that's Chinese-context only; see Gotchas).
curl -X POST http://10.100.79.3:8190/v1/audio/speech \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "cosyvoice-v3",
    "voice": "<voice_id>",
    "input": "<angry>I did not ask for visitors today.</angry>",
    "response_format": "wav",
    "speed": 1.0
  }' \
  -o out.wav

# 5. Or synthesize via native endpoint with streaming — curl writes
#    audio chunks to the file as they arrive (~150 ms TTFB).
#    `instruct_text` here has the same Chinese-only caveat as the
#    OpenAI path's `instruct` — leave it empty for English work.
curl -N -X POST http://10.100.79.3:8190/api/tts \
  -F "text=<angry>I did not ask for visitors today.</angry>" \
  -F "voice=<voice_id>" \
  -F "mode=zero_shot" \
  -F "speed=1.0" \
  -F "stream=true" \
  -o out_stream.pcm
```

Field naming differs between the two synthesis endpoints:

| `/v1/audio/speech` (JSON) | `/api/tts` (multipart) |
|---|---|
| `input` | `text` |
| `instruct` | `instruct_text` |
| `voice` | `voice` (same) |
| `response_format` | — (always wav/pcm chunks) |
| — | `stream` (bool) |
| — | `mode` (`zero_shot` / `instruct` / `sft`) |
| — | `prompt_wav` + `prompt_text` (inline ref audio; skip /v1/voices/create) |

## Emotion / style control

**For English content, use XML inline tags. Do not use the `instruct`
field** — see the Gotcha above; `instruct` routes through CosyVoice's
Chinese-context inference path and English values get spoken aloud
instead of treated as direction.

| Syntax | Where | Example | English-safe? |
|---|---|---|---|
| XML tags in the text | inline in `input` / `text` | `<angry>You're late.</angry>` | ✅ |
| Natural-language directive | `instruct` / `instruct_text` | `"用愤怒的语气说"` (Chinese) | ⚠️ Chinese only |

Tag vocabulary includes `<angry>`, `<sad>`, `<surprised>`,
`<fearful>`, `<fast>`, `<slow>`, `<whisper>`, `<shout>`, plus
character/style tags like `<peppa>`, `<robot>`. Tags can be nested
or applied at sentence granularity (the model accepts paragraph-
length input with multiple tagged segments).

## Version bump

```bash
# Pick a new tag from https://hub.docker.com/r/neosun/cosyvoice/tags
ssh irv-ml1 '
  cd /opt/docker/compose/cosyvoice && \
  sed -i "s/^COSYVOICE_VERSION=.*/COSYVOICE_VERSION=<new-tag>/" .env && \
  docker compose pull && \
  docker compose up -d
'
```

Voices / input / output persist across bumps. Model weights inside
the image re-download on first run of the new tag.