# Stable Audio 3 Medium Audio Outpainting API

> Stable Audio 3 Medium تقطیرشده که صدا را پیش یا پس از کلیپ منبع امتداد می‌دهد

یک قطعه را از `audio_url` با هدایت `prompt` ادامه می‌دهد. `extend_seconds_before` و `extend_seconds_after` هرکدام 0 تا 380 ثانیه صدای جدید اضافه می‌کنند. مقدار پیش‌فرض 8 گام نمونه‌برداری است. خروجی می‌تواند mp3، wav، flac، ogg، opus، m4a یا aac باشد.

- Model id: `stable-audio-3/medium/audio-outpainting`
- Made by: Stability AI
- Category: Audio
- Output: audio
- Price: $0.0446 / request (cheapest run $0.045 (45 API credits))
- Run: `POST https://api.doitong.com/v1/run/stable-audio-3/medium/audio-outpainting`
- Quote: `POST https://api.doitong.com/v1/quote/stable-audio-3/medium/audio-outpainting`
- Docs page: https://doitong.com/fa/developers/models/stable-audio-3/medium/audio-outpainting

## Pricing

Price: **$0.0446 / request**. Billed once per request.

The full example input below costs $0.045 = 45 API credits (1 request × 44.6 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.com/v1/quote/stable-audio-3/medium/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 | `` |  | متنی که ویژگی‌های ناخواسته در خروجی را مشخص می‌کند. |
| `num_inference_steps` |  | integer | no | `8` | 1 – 100 | تعداد تکرارهای نمونه‌برداری؛ مقدار پیش‌فرض 8 است، زیرا نقاط بررسی تقطیرشده و پساآموزش‌دیده در همین مقدار کیفیت خوبی دارند و تکرارهای بیشتر سود کمی ایجاد می‌کنند. |
| `guidance_scale` |  | number | no | `1` | 0 – 25 | قدرت راهنمایی بدون طبقه‌بند، فقط برای نقاط بررسی پایه؛ نقاط بررسی تقطیرشده تحت تأثیر قرار نمی‌گیرند. در نقاط بررسی مربوط، افزایش آن پایبندی به پرامپت را بیشتر می‌کند. |
| `seed` |  | integer \| null | no |  |  | بذر مولد تصادفی برای نتایج تکرارپذیر؛ حذف آن یک بذر تصادفی انتخاب می‌کند. |
| `enable_prompt_expansion` |  | boolean | no | `false` |  | گسترش پرامپت با استفاده از LLM هنگام فعال‌بودن، برای افزودن جزئیات و بهبود کیفیت نتیجه. |
| `enable_safety_checker` |  | boolean | no | `true` |  | بررسی ایمنی برای محتوای NSFW. |
| `output_format` |  | enum (string) | no | `mp3` | `mp3`, `wav`, `flac`, `ogg`, `opus`, `m4a`, `aac` | قالب محفظهٔ صوت حاصل. |
| `bitrate` |  | string | no | `192k` |  | بیت‌ریت صوت خروجی که هنگام استفاده از wav یا flac نادیده گرفته می‌شود، زیرا بدون افت هستند. برای قالب‌های فشرده مانند mp3، aac یا opus، مقداری به‌شکل '192k' یا '320k' ارائه کنید. |
| `prompt` |  | string | yes |  |  | دستورهای متنی که محتوای افزونه را توصیف می‌کنند. |
| `audio_url` | `audio` | string (audio URL) | yes |  |  | صوت ورودی برای گسترش. |
| `extend_seconds_before` |  | number | no | `0` | 0 – 380 | مدت صوت تازه‌تولیدشده، برحسب ثانیه، که پیش از منبع قرار می‌گیرد. |
| `extend_seconds_after` |  | number | no | `0` | 0 – 380 | مدت صوت تازه‌تولیدشده، برحسب ثانیه، که به منبع افزوده می‌شود. |

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.com/v1/run/stable-audio-3/medium/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.com/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.com/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/medium/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.com/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/medium/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.com/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/medium/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/medium/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": 45,
    "usd": "0.045",
    "charged": 45,
    "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.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `audio` | object {url, content_type, file_name, file_size} | کلیپ صوتی تولیدشده. |
| `seed` | integer | seed کنترل‌کننده تصادفی‌بودن هنگام تولید. |
| `prompt` | string | پرامپتی که برای تولید خروجی استفاده شده است. |

## 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 Outpainting](https://doitong.com/developers/models/stable-audio-3/small/music/base/audio-outpainting.md) (`stable-audio-3/small/music/base/audio-outpainting`): $0.0339 / 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

## Links

- HTML page: https://doitong.com/developers/models/stable-audio-3/medium/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/medium/audio-outpainting
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/stable-audio-3/medium/audio-outpainting