# Longcat Single Avatar · Audio to Video API

> 僅由音訊檔案與文字提示詞驅動的說話頭像影片，無需來源圖像

根據 `audio_url` 和描述人物的 `prompt` 生成具唇形同步效果的虛擬人物影片。輸出為 480p 或 720p。`num_segments`（1 到 10）設定長度：第一段約 5.8 秒，之後每段增加 5 秒。`audio_guidance_scale`（1 到 10）控制語音驅動嘴部動作的程度，較高的值可能會誇大動作。

- Model id: `longcat-single-avatar/audio-to-video`
- Made by: Meituan
- Category: Lipsync & Avatars
- Output: video
- Price per second of your output video: from $0.15 / second of output video (cheapest run $0.15 (150 API credits))
- Run: `POST https://api.doitong.ru/v1/run/longcat-single-avatar/audio-to-video`
- Quote: `POST https://api.doitong.ru/v1/quote/longcat-single-avatar/audio-to-video`
- Docs page: https://doitong.com/zh-TW/developers/models/longcat-single-avatar/audio-to-video

## Pricing

Price: **from $0.15 / second of output video** (the lowest tier; the quote prices your exact input). Price per second of your output video: the input files are measured before the run (length, resolution, frame rate). The quote measures the same files and is exactly what the run charges.

Price by tier:

- base rate: $0.15 / second of output video
- 720p: $0.60 / second of output video

The full example input below costs $0.90 = 900 API credits (6 s output video × $0.15).

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/longcat-single-avatar/audio-to-video` 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 |
|---|---|---|---|---|---|---|
| `audio_url` | `audio` | string (audio URL) | yes |  |  | 用於驅動虛擬角色的音訊檔案 URL。 |
| `prompt` |  | string | no | `A person is talking naturally with natural expressions and movements.` |  | 引導影片生成的提示詞。 |
| `negative_prompt` |  | string | no | `Close-up, Bright tones, overexposed, static, blurred details, subtitles, style, works, paintings, images, static, overall gray, worst quality, low quality, JPEG compression residue, ugly, incomplete, extra fingers, poorly drawn hands, poorly drawn faces, deformed, disfigured, misshapen limbs, fused fingers, still picture, messy background, three legs, many people in the background, walking backwards` |  | 指定影片生成應避免內容的負面提示詞。 |
| `num_inference_steps` |  | integer | no | `50` | 10 – 100 | 執行的推論步驟數。 |
| `text_guidance_scale` |  | number | no | `4` | 1 – 10 | 分類器無關引導中套用的文字引導比例。 |
| `audio_guidance_scale` |  | number | no | `4` | 1 – 10 | 音訊引導調整值；提高時可誇大嘴部動作。 |
| `resolution` |  | enum (string) | no | `480p` | `480p`, `720p` | 輸出影片解析度，可以是 480p 或 720p。 |
| `num_segments` |  | integer | no | `1` | 1 – 10 | 影片片段數；初始片段約為 5.8s，後續每個片段為 5s，即每個片段約 5 秒影片。 |
| `seed` |  | integer \| null | no |  |  | 初始化亂數生成的種子值。 |
| `enable_safety_checker` |  | boolean | no | `true` |  | 受帳戶權限限制的安全檢查切換鈕：未授權請求仍必須檢查，停用檢查需要授權。 |
| `enable_prompt_expansion` |  | boolean | no | `false` |  | 以 LLM 為基礎的提示詞擴展切換鈕，透過增強提示詞改善影片品質。 |

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
{
  "audio": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

A fuller example:

```json
{
  "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/longcat-single-avatar/audio-to-video?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "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/longcat-single-avatar/audio-to-video?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "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 = {
    "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/longcat-single-avatar/audio-to-video", 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": "longcat-single-avatar/audio-to-video",
      "input": {
        "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": "longcat-single-avatar/audio-to-video",
  "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": 900,
    "usd": "0.90",
    "charged": 900,
    "refunded": 0
  },
  "input": {
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  },
  "output": {
    "video": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_name": "0-output.mp4",
      "file_size": 1843200
    },
    "seed": 42
  },
  "outputs": [
    {
      "type": "video",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_size": 1843200,
      "width": 1280,
      "height": 720,
      "duration": 5,
      "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 |
|---|---|---|
| `video` | object {url, content_type, file_name, file_size} | 生成產生的影片檔案。 |
| `seed` | integer | 生成期間套用的種子值。 |

## Related models

- [Longcat Single Avatar · Image Audio to Video](https://doitong.com/developers/models/longcat-single-avatar/image-audio-to-video.md) (`longcat-single-avatar/image-audio-to-video`): from $0.15 / second of output video
- [Kling AI Avatar 2.0 Pro](https://doitong.com/developers/models/kling-video/ai-avatar/v2/pro.md) (`kling-video/ai-avatar/v2/pro`): $0.115 / second of input audio
- [Sync Lipsync 3](https://doitong.com/developers/models/sync-lipsync/v3.md) (`sync-lipsync/v3`): $8.00 / minute of output video
- [VEED Fabric 1.0](https://doitong.com/developers/models/veed/fabric-1.0.md) (`veed/fabric-1.0`): from $0.08 / second of input audio
- [Infinitalk](https://doitong.com/developers/models/infinitalk.md) (`infinitalk`): from $0.20 / second of output video
- [Infinitalk · Single Text](https://doitong.com/developers/models/infinitalk/single-text.md) (`infinitalk/single-text`): from $2.32 / run
- [Infinitalk · Video to Video](https://doitong.com/developers/models/infinitalk/video-to-video.md) (`infinitalk/video-to-video`): from $0.30 / second of output video
- [AI Avatar Multi](https://doitong.com/developers/models/ai-avatar/multi.md) (`ai-avatar/multi`): from $0.20 / second of output video

## Links

- HTML page: https://doitong.com/developers/models/longcat-single-avatar/audio-to-video
- 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=longcat-single-avatar/audio-to-video
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/longcat-single-avatar/audio-to-video