# Stable Audio 3 Small Music Base Audio Outpainting API

> Útvíkkun á Small-tónlist með grunn-checkpoint: heldur áfram lagi við hvorn enda, sjálfgefið 50 skref

Lengir tónlistarmyndskeið sem gefið er upp með `audio_url` með textakvaðningu í `prompt`. `extend_seconds_before` og `extend_seconds_after` taka hvort um sig við 0 til 120 sekúndum af nýju hljóði. Þetta er grunnvörðunin, þannig að sjálfgefið er 50 sýnatökuskref og leiðsagnarstuðull 7, með leiðsögn sem hægt er að stilla allt að 25. Úttakssnið eru meðal annars mp3, wav og flac.

- Model id: `stable-audio-3/small/music/base/audio-outpainting`
- Made by: Stability AI
- Category: Text to Music
- Output: audio
- Price: $0.0339 / request (cheapest run $0.034 (34 API credits))
- Run: `POST https://api.doitong.ru/v1/run/stable-audio-3/small/music/base/audio-outpainting`
- Quote: `POST https://api.doitong.ru/v1/quote/stable-audio-3/small/music/base/audio-outpainting`
- Docs page: https://doitong.com/is/developers/models/stable-audio-3/small/music/base/audio-outpainting

## Pricing

Price: **$0.0339 / request**. Billed once per request.

The full example input below costs $0.034 = 34 API credits (1 request × 33.9 API credits).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.ru/v1/quote/stable-audio-3/small/music/base/audio-outpainting` with the same JSON body returns the exact price for that input; the quote is exactly what a run charges. Invalid input is never charged and failed or canceled requests are refunded automatically.

## Input parameters

Send either the canonical name or the native field name (not both). Canonical names are the same across models.

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `negative_prompt` |  | string | no | `` |  | Texti sem tilgreinir óæskilega eiginleika í úttakinu. |
| `num_inference_steps` |  | integer | no | `50` | 1 – 100 | Veldu fjölda sýnatökuþrepa; um 50 geta gefið góð gæði þegar grunn-checkpoint, sem eru ekki eimuð, eru notuð. |
| `guidance_scale` |  | number | no | `7` | 0 – 25 | Styrkur classifier-free guidance, þar sem mælt er með um 7.0 í upphafi á grunn-checkpoint; hækkun hans lætur efnisgerð fylgja kvaðningunni nánar. |
| `seed` |  | integer \| null | no |  |  | Fræ slembigjafa fyrir endurtekjanlegar niðurstöður; ef því er sleppt er slembifræ valið. |
| `enable_prompt_expansion` |  | boolean | no | `false` |  | Útvíkkun kvaðningar með LLM þegar hún er virkjuð, sem bætir við smáatriðum og eykur gæði niðurstöðu. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Öryggisathugun á NSFW-efni. |
| `output_format` |  | enum (string) | no | `mp3` | `mp3`, `wav`, `flac`, `ogg`, `opus`, `m4a`, `aac` | Gámssnið sem er notað fyrir hljóðið í niðurstöðunni. |
| `bitrate` |  | string | no | `192k` |  | Bitahraði úttakshljóðs, hunsaður þegar wav eða flac er notað þar sem þau eru taplaus. Fyrir þjöppuð snið á borð við mp3, aac eða opus skal gefa upp gildi á forminu '192k' eða '320k'. |
| `prompt` |  | string | yes |  |  | Textaleiðbeiningar sem lýsa innihaldi viðbótarinnar. |
| `audio_url` | `audio` | string (audio URL) | yes |  |  | Inntakshljóð fyrir viðbót. |
| `extend_seconds_before` |  | number | no | `0` | 0 – 120 | Lengd í sekúndum á nýmynduðu hljóði sem er sett framan við upprunann. |
| `extend_seconds_after` |  | number | no | `0` | 0 – 120 | Lengd í sekúndum á nýmynduðu hljóði sem er bætt aftan við upprunann. |

File parameters (`audio`) take a public `https://` URL, a `data:` URI up to 10 MB, or the `file_url` of an upload from `POST /files`.

## Example input

Required parameters only:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "audio": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

A fuller example:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

## Run it

Set `DOITONG_API_KEY` to a key from https://doitong.com/developers/dashboard#keys. `?wait=20` returns the finished request in the same call when it is ready within 20 seconds; otherwise poll `GET /requests/{id}` (it also accepts `?wait=`), or pass `webhook_url`.

### curl

```bash
# Run the model; wait up to 20 s for the finished result in the same call
curl -X POST "https://api.doitong.ru/v1/run/stable-audio-3/small/music/base/audio-outpainting?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  }'

# Still "queued" or "running"? Poll with the id from the response:
curl "https://api.doitong.ru/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.ru/v1";
const headers = {
  "Authorization": "Bearer " + process.env.DOITONG_API_KEY,
  "Content-Type": "application/json",
};

// Run the model; wait up to 20 s for the finished result in the same call
let res = await fetch(API + "/run/stable-audio-3/small/music/base/audio-outpainting?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  }),
});
let request = await res.json();
if (!res.ok) throw new Error(request.error.code + ": " + request.error.message);

// Not finished yet: long-poll until it is
while (request.status === "queued" || request.status === "running") {
  res = await fetch(API + "/requests/" + request.id + "?wait=20", { headers });
  request = await res.json();
}
if (request.status !== "succeeded") throw new Error(JSON.stringify(request.error));
console.log(request.outputs.map((o) => o.url), request.cost.credits + " API credits ($" + request.cost.usd + ")");
```

### Python

```python
import os
import requests

API = "https://api.doitong.ru/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/stable-audio-3/small/music/base/audio-outpainting", params={"wait": 20}, json=payload, headers=headers)
request = r.json()
if not r.ok:
    raise RuntimeError(request["error"]["code"] + ": " + request["error"]["message"])

# Not finished yet: long-poll until it is
while request["status"] in ("queued", "running"):
    request = requests.get(API + "/requests/" + request["id"], params={"wait": 20}, headers=headers).json()
if request["status"] != "succeeded":
    raise RuntimeError(request["error"])
print([o["url"] for o in request["outputs"]], request["cost"]["credits"], "API credits", "$" + request["cost"]["usd"])
```

### MCP

The MCP server at `https://api.doitong.ru/v1/mcp` exposes the tools `search_models`, `get_model`, `quote`, `run`, `get_request`, `cancel_request`, `list_requests`, `create_upload` and `get_account`. A `run` call for this model:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "run",
    "arguments": {
      "model_id": "stable-audio-3/small/music/base/audio-outpainting",
      "input": {
        "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
        "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
      },
      "wait_seconds": 20
    }
  }
}
```

## Response

Every call returns a request object. `status` is one of `queued`, `running`, `succeeded`, `failed`, `canceled`. `outputs` lists the generated files with URLs on our storage (kept forever, or 7 days with `?storage=temporary`; `storage` says which); `output` is the model's own result object with the same URLs.

```json
{
  "id": "req_8k2m4q7x1z9c3v5b6n0p2r4t",
  "object": "request",
  "model": "stable-audio-3/small/music/base/audio-outpainting",
  "status": "succeeded",
  "created_at": "2026-10-20T12:00:00Z",
  "started_at": "2026-10-20T12:00:02Z",
  "completed_at": "2026-10-20T12:00:09Z",
  "queue_position": null,
  "cost": {
    "credits": 34,
    "usd": "0.034",
    "charged": 34,
    "refunded": 0
  },
  "input": {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  },
  "output": {
    "audio": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp3",
      "content_type": "audio/mpeg",
      "file_name": "0-output.mp3",
      "file_size": 1843200
    },
    "seed": 42,
    "prompt": "string"
  },
  "outputs": [
    {
      "type": "audio",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp3",
      "content_type": "audio/mpeg",
      "file_size": 1843200,
      "duration": 12,
      "stored": true
    }
  ],
  "error": null,
  "metrics": {
    "inference_seconds": 6.8
  },
  "urls": {
    "self": "https://api.doitong.ru/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.ru/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `audio` | object {url, content_type, file_name, file_size} | Hljóðbútur sem myndaður er með efnisgerð. |
| `seed` | integer | Sáð sem stýrði slembni við efnisgerð. |
| `prompt` | string | Kvaðningin sem notuð var til að búa til úttakið. |

## Related models

- [Stable Audio 3 Small Music Audio Inpainting](https://doitong.com/developers/models/stable-audio-3/small/music/audio-inpainting.md) (`stable-audio-3/small/music/audio-inpainting`): $0.026 / request
- [Stable Audio 3 Small Music Audio Outpainting](https://doitong.com/developers/models/stable-audio-3/small/music/audio-outpainting.md) (`stable-audio-3/small/music/audio-outpainting`): $0.0265 / request
- [Stable Audio 3 Small Music Base Audio Inpainting](https://doitong.com/developers/models/stable-audio-3/small/music/base/audio-inpainting.md) (`stable-audio-3/small/music/base/audio-inpainting`): $0.0333 / request
- [Stable Audio 3 Small Music Base Audio to Audio](https://doitong.com/developers/models/stable-audio-3/small/music/base/audio-to-audio.md) (`stable-audio-3/small/music/base/audio-to-audio`): $0.032 / request
- [Stable Audio 3 Small Music Text to Audio](https://doitong.com/developers/models/stable-audio-3/small/music/text-to-audio.md) (`stable-audio-3/small/music/text-to-audio`): $0.0217 / request
- [Stable Audio 3 · Small · Music · Audio to Audio](https://doitong.com/developers/models/stable-audio-3/small/music/audio-to-audio.md) (`stable-audio-3/small/music/audio-to-audio`): $0.0248 / request
- [Stable Audio 3 · Small · Music · Base · Text to Audio](https://doitong.com/developers/models/stable-audio-3/small/music/base/text-to-audio.md) (`stable-audio-3/small/music/base/text-to-audio`): $0.0281 / request
- [Stable Audio 3 Medium Audio Inpainting](https://doitong.com/developers/models/stable-audio-3/medium/audio-inpainting.md) (`stable-audio-3/medium/audio-inpainting`): $0.0442 / request

## Links

- HTML page: https://doitong.com/developers/models/stable-audio-3/small/music/base/audio-outpainting
- All models and guides for AI agents: https://doitong.com/developers/llms.txt
- OpenAPI 3.1 with this model's typed request body: https://doitong.com/developers/openapi.json?model=stable-audio-3/small/music/base/audio-outpainting
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/stable-audio-3/small/music/base/audio-outpainting