# Ltx 2.5 Audio to Video Fast API

> Geschwindigkeitsoptimierte Videogenerierung passend zu einem bereitgestellten Audioclip, optional mit Bild für das erste Frame

Erstellt ein Video passend zu einem über `audio_url` angegebenen Audioclip, der 2 bis 20 Sekunden lang sein muss. Sie können ein `image_url` als erstes Frame hinzufügen oder das Video mit einem bis zu 5000 Zeichen langen `prompt` beschreiben; eines von beiden ist erforderlich. `aspect_ratio` ist auto, 16:9 oder 9:16. Dies ist der schnellere Modus der Familie.

- Model id: `lightricks/ltx-2.5/audio-to-video/fast`
- Made by: Lightricks
- Category: Lipsync & Avatars
- Output: video
- Price per second of your input audio: $0.13 / second of input audio (cheapest run $0.13 (130 API credits))
- Run: `POST https://api.doitong.ru/v1/run/lightricks/ltx-2.5/audio-to-video/fast`
- Quote: `POST https://api.doitong.ru/v1/quote/lightricks/ltx-2.5/audio-to-video/fast`
- Docs page: https://doitong.com/de/developers/models/lightricks/ltx-2.5/audio-to-video/fast

## Pricing

Price: **$0.13 / second of input audio**. Price per second of your input 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 $1.30 = 1300 API credits (10 s input audio × $0.13).

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/lightricks/ltx-2.5/audio-to-video/fast` 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 |  |  | URL einer Audiodatei als Quelle für die Videogenerierung; gib eine öffentlich zugängliche URL oder eine Base64-Daten-URI an. Die Audiodauer muss zwischen 2–20 Sekunden liegen, bei Pro-Modellen maximal 10 Sekunden. |
| `image_url` | `image` | string (image URL) \| null | no |  |  | URL des Bildes für den Start-Frame; bei Auslassung ist ein Prompt erforderlich. |
| `prompt` |  | string \| null | no |  | 1 – 5000 characters | Videoanweisungen, deren Rolle von `image_url` abhängt: Mit einem Bild geben sie dessen Animation an; ohne Bild müssen sie das zu generierende Video beschreiben. |
| `aspect_ratio` |  | enum (string) | no | `auto` | `auto`, `16:9`, `9:16` | Seitenverhältnis des Videos; 'auto' wählt bei bereitgestelltem Eingabe-Bild ein vom Bild abgeleitetes Verhältnis und andernfalls 16:9. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Die Prüfung kann durch Setzen auf false gelockert werden, sofern der Aufrufer dazu berechtigt ist. |

File parameters (`audio`, `image`) 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/lightricks/ltx-2.5/audio-to-video/fast?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/lightricks/ltx-2.5/audio-to-video/fast?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/lightricks/ltx-2.5/audio-to-video/fast", 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": "lightricks/ltx-2.5/audio-to-video/fast",
      "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": "lightricks/ltx-2.5/audio-to-video/fast",
  "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": 1300,
    "usd": "1.30",
    "charged": 1300,
    "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,
      "width": 1024,
      "height": 768,
      "fps": 1.0,
      "duration": 5,
      "num_frames": 1
    }
  },
  "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, width, height, fps, duration, num_frames} | Resultierende Videodatei. |

## Related models

- [LTX 2.5 Pro Text to Video](https://doitong.com/developers/models/lightricks/ltx-2.5/text-to-video/pro.md) (`lightricks/ltx-2.5/text-to-video/pro`): from $0.12 / second
- [Ltx 2.5 Text to Video Fast](https://doitong.com/developers/models/lightricks/ltx-2.5/text-to-video/fast.md) (`lightricks/ltx-2.5/text-to-video/fast`): from $0.09 / second
- [LTX 2.5 Image to Video Fast](https://doitong.com/developers/models/lightricks/ltx-2.5/image-to-video/fast.md) (`lightricks/ltx-2.5/image-to-video/fast`): from $0.09 / second
- [LTX 2.5 Pro Image to Video](https://doitong.com/developers/models/lightricks/ltx-2.5/image-to-video/pro.md) (`lightricks/ltx-2.5/image-to-video/pro`): from $0.12 / second
- [Ltx 2.5 Audio to Video Pro](https://doitong.com/developers/models/lightricks/ltx-2.5/audio-to-video/pro.md) (`lightricks/ltx-2.5/audio-to-video/pro`): $0.17 / second of input audio
- [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

## Links

- HTML page: https://doitong.com/developers/models/lightricks/ltx-2.5/audio-to-video/fast
- 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=lightricks/ltx-2.5/audio-to-video/fast
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/lightricks/ltx-2.5/audio-to-video/fast