# Ffmpeg Api · Loudnorm API

> Normaliza a intensidade do áudio para um alvo EBU R128 com configurações ajustáveis de LUFS, pico real e faixa

Aplica normalização de intensidade ao arquivo em `audio_url`. Os alvos incluem `integrated_loudness` (-70 a -5 LUFS), `true_peak` (-9 a 0 dBTP) e `loudness_range` (1 a 20 LU). O modo dinâmico de duas passagens é o padrão. O modo linear de uma passagem precisa dos valores medidos da entrada, e um resumo da medição pode ser retornado.

- Model id: `ffmpeg-api/loudnorm`
- Made by: Utility
- Category: Audio
- Output: audio
- Charged by usage (up to $0.306 per run, typical $0.001; the rest of the hold is refunded): $0.00017 / second of processing time (cheapest run $0.001 (1 API credit))
- Run: `POST https://api.doitong.com/v1/run/ffmpeg-api/loudnorm`
- Quote: `POST https://api.doitong.com/v1/quote/ffmpeg-api/loudnorm`
- Docs page: https://doitong.com/pt-BR/developers/models/ffmpeg-api/loudnorm

## Pricing

Price: **$0.00017 / second of processing time**. Charged by actual usage at $0.00017 / second of processing time: up to $0.306 per run (the quote gives the maximum for your input), the rest is refunded automatically after the run. A typical run costs $0.001.

The full example input below holds up to $0.306 = 306 API credits (up to 1800 s of processing time × $0.00017) when it starts; a typical run costs $0.001 (1 API credit).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). This model is charged by usage: `POST https://api.doitong.com/v1/quote/ffmpeg-api/loudnorm` with the same JSON body returns the most the run can cost for that input (`credits`, debited when the run starts); after the run you pay the usage the model reports and the rest is refunded automatically. An input whose maximum would exceed the per-run limit is refused with 422. 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 |  |  | URL que aponta para o arquivo de áudio que requer normalização. |
| `integrated_loudness` |  | number | no | `-18` | -70 – -5 | Valor-alvo da intensidade sonora integrada, expresso em LUFS. |
| `true_peak` |  | number | no | `-0.1` | -9 – 0 | Limite de pico verdadeiro, expresso em dBTP. |
| `loudness_range` |  | number | no | `7` | 1 – 20 | Intervalo-alvo da intensidade sonora, expresso em LU. |
| `offset` |  | number | no | `0` | -99 – 99 | Deslocamento de ganho, expresso em dB, aplicado antes do limitador de pico verdadeiro. |
| `linear` |  | boolean | no | `false` |  | Seletor do modo de normalização: false escolhe a abordagem dinâmica de maior qualidade em duas passagens; true escolhe o processamento linear de uma passagem. |
| `dual_mono` |  | boolean | no | `false` |  | Indica se as entradas mono são tratadas como mono duplo para que as medições de intensidade sonora EBU R128 sejam corretas em sistemas estéreo. |
| `print_summary` |  | boolean | no | `false` |  | Inclui um resumo das medições de intensidade sonora junto com o áudio normalizado. |
| `measured_i` |  | number \| null | no |  | -99 – 0 | Medição da intensidade sonora integrada que o modo linear exige do arquivo de entrada, fornecida em LUFS. |
| `measured_lra` |  | number \| null | no |  | 0 – 99 | Medição do intervalo de intensidade sonora necessária pelo modo linear, obtida do arquivo de entrada e fornecida em LU. |
| `measured_tp` |  | number \| null | no |  | -99 – 99 | Medição do pico verdadeiro exigida pelo modo linear, fornecida em dBTP a partir do arquivo de entrada. |
| `measured_thresh` |  | number \| null | no |  | -99 – 0 | Limiar medido do áudio de entrada, expresso em LUFS; obrigatório ao usar o modo linear. |

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.com/v1/run/ffmpeg-api/loudnorm?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.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/ffmpeg-api/loudnorm?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.com/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/ffmpeg-api/loudnorm", 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": "ffmpeg-api/loudnorm",
      "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": "ffmpeg-api/loudnorm",
  "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": 306,
    "usd": "0.306",
    "charged": 306,
    "refunded": 0
  },
  "input": {
    "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
    },
    "summary": {
      "input_integrated": 1.0,
      "input_true_peak": 1.0,
      "input_lra": 1.0,
      "input_threshold": 1.0,
      "output_integrated": 1.0,
      "output_true_peak": 1.0,
      "output_lra": 1.0,
      "output_threshold": 1.0,
      "normalization_type": "string",
      "target_offset": 1.0
    }
  },
  "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} | Arquivo de áudio após a normalização. |
| `summary` | object {input_integrated, input_true_peak, input_lra, input_threshold, output_integrated, output_true_peak, output_lra, output_threshold, normalization_type, target_offset} \| null | Resumo estruturado das medições de intensidade sonora, retornado quando solicitado. |

## Related models

- [Ffmpeg Api Images to Video](https://doitong.com/developers/models/ffmpeg-api/images-to-video.md) (`ffmpeg-api/images-to-video`): $0.005 / run
- [Ffmpeg Api · Merge Videos](https://doitong.com/developers/models/ffmpeg-api/merge-videos.md) (`ffmpeg-api/merge-videos`): $0.00017 / second of processing time
- [FFmpeg API Metadata](https://doitong.com/developers/models/ffmpeg-api/metadata.md) (`ffmpeg-api/metadata`): $0.001 / run
- [FFmpeg API Waveform](https://doitong.com/developers/models/ffmpeg-api/waveform.md) (`ffmpeg-api/waveform`): $0.001 / run
- [MMAudio V2](https://doitong.com/developers/models/mmaudio-v2.md) (`mmaudio-v2`): $0.001 / second
- [FFmpeg API \[Merge Audios\]](https://doitong.com/developers/models/ffmpeg-api/merge-audios.md) (`ffmpeg-api/merge-audios`): $0.00017 / second of processing time
- [Workflow Utilities Audio Compressor](https://doitong.com/developers/models/workflow-utilities/audio-compressor.md) (`workflow-utilities/audio-compressor`): $0.001 / second of processing time
- [Workflow Utilities Impulse Response](https://doitong.com/developers/models/workflow-utilities/impulse-response.md) (`workflow-utilities/impulse-response`): $0.001 / second of processing time

## Links

- HTML page: https://doitong.com/developers/models/ffmpeg-api/loudnorm
- 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=ffmpeg-api/loudnorm
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/ffmpeg-api/loudnorm