# Mirelo SFX2.0 · Video to Audio API

> Cria uma banda sonora para um vídeo de entrada e devolve-a como ficheiros de áudio separados

Adiciona som a um clipe fornecido em `video_url`, devolvendo ficheiros de áudio sem o vídeo. `text_prompt` e `negative_prompt` orientam o resultado, enquanto `preserve_speech` mantém a fala existente ao gerar o restante. `duration` varia entre 1 e 600 segundos, limitada à duração do vídeo, e `num_samples` fornece 1 a 4 variações. Os formatos são wav, mp3, aac ou 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/pt-PT/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 |  |  | URL do vídeo que irá receber o som. |
| `text_prompt` |  | string \| null | no |  | ≤ 2000 characters | Instruções de texto opcionais para orientar a geração. |
| `negative_prompt` |  | string \| null | no |  | ≤ 1000 characters | Lista breve de exclusão de sons, com vírgulas entre as entradas. |
| `preserve_speech` |  | boolean | no | `true` |  | Tratamento da fala para a banda sonora gerada: false suprime a fala e produz apenas efeitos sonoros. Quando ativado, a fala de entrada permanece intacta e o resto da banda sonora é gerado à sua volta. |
| `duration` |  | number | no | `10` | 1 – 600 | Duração do som solicitada em segundos; vídeos com menos de 1 s devolvem 400. A duração solicitada deve ser de pelo menos 1 s e é limitada à duração do vídeo, sendo a geração dividida em janelas de 10 s quando a duração excede 10 s. |
| `num_samples` |  | integer | no | `2` | 1 – 4 | Número de variações a produzir. |
| `seed` |  | integer \| null | no |  | -1 – 18,446,744,073,709,552,000 | Seed de geração; escolher -1 ou None utiliza um valor aleatório. |
| `upload_audio_format` |  | enum (string) | no | `wav` | `wav`, `mp3`, `aac`, `flac` | Formato utilizado para cada ficheiro de áudio. |
| `upload_audio_bitrate_kbps` |  | integer \| null | no |  | 32 – 320 | Substituição da taxa de bits de carregamento em kbps, rejeitada quando upload_audio_format não tem perdas; deixá-la não configurada preserva LAME V0 VBR para mp3 ou um alvo de 256 kbps para aac. Para mp3, escolha uma taxa constante exata entre 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320. Para aac, os valores de 32 a 256 especificam um alvo do codificador em vez de uma taxa garantida, pelo que áudio mono ou esparso pode ficar abaixo desse valor. |

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 | Versão do modelo SFX utilizada para produzir a saída. |
| `audio` | array of object {url, content_type, file_name, file_size} | Ficheiros de áudio das bandas sonoras geradas, excluindo o vídeo. |

## 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