# H3 Max Turbo Extend Video API

> Amplía un vídeo fuente de 1.625 a 60 segundos con entre 0.71 y 15 segundos de metraje nuevo guiado por un prompt

Continúa un vídeo de `video_url` (hasta 50 MB) añadiendo metraje nuevo descrito en `prompt`. `duration` define la duración añadida entre 0.71 y 15 segundos, y la resolución va de 480P a 2K. `output` devuelve el vídeo ampliado completo o solo el clip de continuación. Hasta 3 `reference_audio_urls` pueden guiar el audio.

- Model id: `minimax/h3-max-turbo/extend-video`
- Made by: MiniMax
- Category: Video to Video
- Output: video
- Price: from $0.025 / second (5 s ≈ $0.125) (cheapest run $0.125 (125 API credits))
- Run: `POST https://api.doitong.ru/v1/run/minimax/h3-max-turbo/extend-video`
- Quote: `POST https://api.doitong.ru/v1/quote/minimax/h3-max-turbo/extend-video`
- Docs page: https://doitong.com/es-ES/developers/models/minimax/h3-max-turbo/extend-video

## Pricing

Price: **from $0.025 / second (5 s ≈ $0.125)** (the lowest tier; the quote prices your exact input). Billed per second of output (`duration`, default 15).

Price rules (the first rule that matches the input wins; a parameter you leave out counts as its default):

- When `resolution` = 768P: $0.04 (40 API credits) / second
- When `resolution` = 1080P: $0.08 (80 API credits) / second
- When `resolution` = 2K: $0.16 (160 API credits) / second

The full example input below costs $0.20 = 200 API credits (5 s × 40 API credits).

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/minimax/h3-max-turbo/extend-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 |
|---|---|---|---|---|---|---|
| `video_url` | `video` | string (video URL) | yes |  | ≥ 1 characters | URL del vídeo de origen para la extensión; el archivo no debe superar 50 MB. Los vídeos admitidos tienen una relación de aspecto de 0.4–2.5 y una duración de 1.625 s–60 s. |
| `prompt` |  | string | yes |  | 1 – 50000 characters | Descripción de los acontecimientos que deben continuar, no una descripción del metraje de origen. |
| `reference_audio_urls` |  | array of audio URL | no |  | ≤ 3 items | Clips opcionales que guían el nuevo audio de la continuación en lugar de la banda sonora de origen; especifica sus funciones en el prompt, por ejemplo 'Audio 1 for the voice' y 'Audio 2 for background music'. Cada uno debe durar 2–15 segundos, con un máximo de 15 segundos entre todos los clips. El vídeo extendido completo conserva la banda sonora original, cuyo final sigue guiando la transición. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Mejora del prompt guiada por el origen para lograr una continuación más coherente. Al activarla, el sistema puede revisar el prompt automáticamente, pero el procesamiento puede tardar más. |
| `duration` |  | number | no | `5` | 0.71 – 15 | Cantidad solicitada de metraje nuevo, medida en segundos en lugar de la duración total del clip de continuación. Este clip también conserva los últimos 1.625 segundos del origen, y el redondeo de fotogramas puede añadir tiempo adicional. |
| `resolution` |  | enum (string) | no | `768P` | `480P`, `768P`, `1080P`, `2K` | Resolución del vídeo resultante. |
| `aspect_ratio` |  | enum (string) | no | `auto` | `auto`, `21:9`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | Proporciones de salida: seleccionar una relación aplica un recorte para adaptarse a ella, mientras que 'auto' utiliza la relación de aspecto del vídeo de origen. |
| `seed` |  | integer \| null | no |  |  | Semilla de generación de la continuación; si no se especifica, se utiliza un valor aleatorio. |
| `output` |  | enum (string) | no | `extended` | `extended`, `continuation` | Modo de salida: 'continuation' proporciona el metraje nuevo precedido por una repetición de 1.625 segundos del final del origen. Para recibir el origen unido al metraje nuevo en un único vídeo, elige 'extended'. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Moderación tanto del vídeo de entrada como del prompt. |

File parameters (`video`, `reference_audio_urls`) 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",
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field"
}
```

A fuller example:

```json
{
  "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field"
}
```

## 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/minimax/h3-max-turbo/extend-video?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",
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field"
  }'

# 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/minimax/h3-max-turbo/extend-video?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field"
  }),
});
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",
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/minimax/h3-max-turbo/extend-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": "minimax/h3-max-turbo/extend-video",
      "input": {
        "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
        "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field"
      },
      "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": "minimax/h3-max-turbo/extend-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": 200,
    "usd": "0.20",
    "charged": 200,
    "refunded": 0
  },
  "input": {
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field"
  },
  "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,
    "duration": 5,
    "source": {},
    "expanded_prompt": "string",
    "timings": {}
  },
  "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} | Vídeo resultante, con una repetición inicial de 1.625 segundos cuando se utiliza el modo 'continuation'. |
| `seed` | integer | Semilla aplicada al generar la continuación. |
| `duration` | number | Duración del vídeo devuelto en segundos. |
| `source` | object | Metadatos del metraje de origen que incluyen dimensiones (ancho y alto), frecuencia de fotogramas, duración y audio. |
| `expanded_prompt` | string \| null | Texto del prompt ampliado o null si no se realizaron cambios. |
| `timings` | object |  |

## Related models

- [H3 Max Turbo Text to Video](https://doitong.com/developers/models/minimax/h3-max-turbo/text-to-video.md) (`minimax/h3-max-turbo/text-to-video`): from $0.0163 / second of output video
- [H3 Max Turbo Image to Video](https://doitong.com/developers/models/minimax/h3-max-turbo/image-to-video.md) (`minimax/h3-max-turbo/image-to-video`): from $0.0163 / second of output video
- [H3 Max](https://doitong.com/developers/models/minimax/h3-max/insert-video.md) (`minimax/h3-max/insert-video`): from $0.05 / second
- [H3 Max Extend Video](https://doitong.com/developers/models/minimax/h3-max/extend-video.md) (`minimax/h3-max/extend-video`): from $0.05 / second of output video
- [H3 Max Recast](https://doitong.com/developers/models/minimax/h3-max/recast.md) (`minimax/h3-max/recast`): from $0.30 / second of input video
- [H3 Max Reframe](https://doitong.com/developers/models/minimax/h3-max/reframe-video.md) (`minimax/h3-max/reframe-video`): from $0.05 / second of input video
- [H3 Max Relight](https://doitong.com/developers/models/minimax/h3-max/relight.md) (`minimax/h3-max/relight`): from $0.05 / second of input video
- [AMT Interpolation](https://doitong.com/developers/models/amt-interpolation.md) (`amt-interpolation`): $0.000575 / second of processing time

## Links

- HTML page: https://doitong.com/developers/models/minimax/h3-max-turbo/extend-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=minimax/h3-max-turbo/extend-video
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/minimax/h3-max-turbo/extend-video