# Mirelo SFX2.0 · Video to Audio API

> 为输入视频创建配乐，并以独立音频文件返回

为 `video_url` 中的视频片段添加声音，仅返回音频文件，不包含视频。`text_prompt` 和 `negative_prompt` 用于引导结果，`preserve_speech` 会在生成其余声音的同时保留现有语音。`duration` 为 1 到 600 秒，并会限制为视频长度；`num_samples` 可生成 1 到 4 个变体。格式为 wav、mp3、aac 或 flac。

- Model id: `mirelo-ai/sfx2.0/video-to-audio`
- Made by: Mirelo AI
- Category: Video to Audio
- Output: audio
- Price per second of your output audio: $0.01 / second of output audio (cheapest run $0.01 (10 API credits))
- Run: `POST https://api.doitong.ru/v1/run/mirelo-ai/sfx2.0/video-to-audio`
- Quote: `POST https://api.doitong.ru/v1/quote/mirelo-ai/sfx2.0/video-to-audio`
- Docs page: https://doitong.com/zh/developers/models/mirelo-ai/sfx2.0/video-to-audio

## Pricing

Price: **$0.01 / second of output audio**. Price per second of your output audio: 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.

The full example input below costs $0.20 = 200 API credits (20 s output audio × $0.01).

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/mirelo-ai/sfx2.0/video-to-audio` 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 |
|---|---|---|---|---|---|---|
| `video_url` | `video` | string (video URL) | yes |  |  | 将接收声音的视频 URL。 |
| `text_prompt` |  | string \| null | no |  | ≤ 2000 characters | 用于指导生成的可选文本说明。 |
| `negative_prompt` |  | string \| null | no |  | ≤ 1000 characters | 简短的声音排除列表，条目之间用逗号分隔。 |
| `preserve_speech` |  | boolean | no | `true` |  | 生成音轨的语音处理方式：false 会抑制语音，仅生成音效。启用后，输入语音保持不变，其余音轨围绕语音生成。 |
| `duration` |  | number | no | `10` | 1 – 600 | 请求的声音时长，以秒为单位；低于 1 s 的视频返回 400。请求长度至少为 1 s，且上限为视频时长；当时长超过 10 s 时，生成会拆分为 10 s 的窗口。 |
| `num_samples` |  | integer | no | `2` | 1 – 4 | 要生成的变体数量。 |
| `seed` |  | integer \| null | no |  | -1 – 18,446,744,073,709,552,000 | 生成种子；选择 -1 或 None 时使用随机值。 |
| `upload_audio_format` |  | enum (string) | no | `wav` | `wav`, `mp3`, `aac`, `flac` | 每个音频文件使用的格式。 |
| `upload_audio_bitrate_kbps` |  | integer \| null | no |  | 32 – 320 | 上传比特率覆盖值，单位为 kbps；当 upload_audio_format 为无损格式时会被拒绝。未设置时，mp3 保留 LAME V0 VBR，aac 使用 256 kbps 目标值。对于 mp3，请从 32、40、48、56、64、80、96、112、128、160、192、224、256、320 中选择精确的恒定速率。对于 aac，32 到 256 的值指定编码器目标而非保证速率，因此单声道或稀疏音频可能低于该值。 |

File parameters (`video`) 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
{
  "video": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
}
```

A fuller example:

```json
{
  "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
}
```

## 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/mirelo-ai/sfx2.0/video-to-audio?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
  }'

# 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/mirelo-ai/sfx2.0/video-to-audio?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
  }),
});
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 = {
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/mirelo-ai/sfx2.0/video-to-audio", 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": "mirelo-ai/sfx2.0/video-to-audio",
      "input": {
        "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
      },
      "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": "mirelo-ai/sfx2.0/video-to-audio",
  "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": 200,
    "usd": "0.20",
    "charged": 200,
    "refunded": 0
  },
  "input": {
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
  },
  "output": {
    "model": "sfx-2.0",
    "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
      }
    ]
  },
  "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 |
|---|---|---|
| `model` | string | 用于生成输出的 SFX 模型版本。 |
| `audio` | array of object {url, content_type, file_name, file_size} | 生成音轨的音频文件，不包含视频。 |

## Related models

- [Mirelo SFX2.0 · Video to Video](https://doitong.com/developers/models/mirelo-ai/sfx2.0/video-to-video.md) (`mirelo-ai/sfx2.0/video-to-video`): $0.01 / second of output audio
- [Mirelo SFX2.0 · Text to Audio](https://doitong.com/developers/models/mirelo-ai/sfx2.0/text-to-audio.md) (`mirelo-ai/sfx2.0/text-to-audio`): $0.01 / second of output audio
- [Hunyuan Video Foley](https://doitong.com/developers/models/hunyuan-video-foley.md) (`hunyuan-video-foley`): $0.10 / 10 seconds of input video
- [Kling Video · Video to Audio](https://doitong.com/developers/models/kling-video/video-to-audio.md) (`kling-video/video-to-audio`): $0.035 / video
- [PixVerse Sound Effects](https://doitong.com/developers/models/pixverse/sound-effects.md) (`pixverse/sound-effects`): $0.10 / 5 seconds of input video
- [Sam Audio · Visual Separate](https://doitong.com/developers/models/sam-audio/visual-separate.md) (`sam-audio/visual-separate`): from $0.05 / 30 seconds of input video
- [Sonilo V1.1](https://doitong.com/developers/models/sonilo/v1.1/video-to-music.md) (`sonilo/v1.1/video-to-music`): $0.009 / second of output audio
- [Sonilo V1.1 Video to Sound Effects](https://doitong.com/developers/models/sonilo/v1.1/video-to-sound-effects.md) (`sonilo/v1.1/video-to-sound-effects`): $0.009 / second of input video

## Links

- HTML page: https://doitong.com/developers/models/mirelo-ai/sfx2.0/video-to-audio
- 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=mirelo-ai/sfx2.0/video-to-audio
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/mirelo-ai/sfx2.0/video-to-audio