# LTX-2.3 22B · Extend Video API

> Leanann sé físeán atá ann cheana ó leid, le fuaim ghinte agus íomhá dheiridh roghnach

Glacann sé `video_url` agus `prompt` agus gineann sé leanúint de `num_frames` fráma (9 go 481). Socraíonn `end_image_url` roghnach an pointe ina gcríochnaíonn an síneadh. Coinníonn `match_input_fps` ráta fráma na foinse, cuireann `generate_audio` fuaim leis, agus bíonn `video_size` auto de réir réamhshocraithe. Is féidir leis an aschur a bheith mp4, webm, mov nó GIF.

- Model id: `ltx-2.3-22b/extend-video`
- Made by: Lightricks
- Category: Video to Video
- Output: video
- Price per megapixel of your output video: $0.00161 / megapixel of output video (cheapest run $0.002 (2 API credits))
- Run: `POST https://api.doitong.com/v1/run/ltx-2.3-22b/extend-video`
- Quote: `POST https://api.doitong.com/v1/quote/ltx-2.3-22b/extend-video`
- Docs page: https://doitong.com/ga/developers/models/ltx-2.3-22b/extend-video

## Pricing

Price: **$0.00161 / megapixel of output video**. Price per megapixel of your output video: 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 $0.18 = 180 API credits (112 MP output video × $0.001605).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.com/v1/quote/ltx-2.3-22b/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 |
|---|---|---|---|---|---|---|
| `prompt` |  | string | yes |  |  | Leid a úsáidtear mar bhonn do ghiniúint físeáin. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL a dhíríonn ar an bhfíseán a leathnófar. |
| `end_image_url` | `end_image` | string (image URL) \| null | no |  |  | Soláthair íomhá an fhráma deiridh trí URL chun a shainiú conas a chríochnaíonn an físeán leathnaithe. |
| `num_frames` |  | integer | no | `121` | 9 – 481 | Líon na bhfrámaí don aschur ginte. |
| `video_size` |  | object {width, height} \| enum (string) | no | `auto` | `auto`, `square_hd`, `square`, `portrait_4_3`, `portrait_16_9`, `landscape_4_3`, `landscape_16_9` | Toisí an fhíseáin ghinte. |
| `generate_audio` |  | boolean | no | `true` |  | Rialaíonn sé an gcuirtear fuaim ghinte san fhíseán. |
| `use_multiscale` |  | boolean | no | `true` |  | Scorán giniúna ilscála le haghaidh comhleanúnachais agus mionsonraí níos fearr. Le True, treoraíonn físeán beag réamhthosaigh an dara giniúint a bhfuil a mhéid cothrom leis na toisí iarrtha nó níos mó. |
| `match_input_fps` |  | boolean | no | `true` |  | Sárú ar ráta fráma aschuir a chuireann FPS fhíseán na foinse in ionad an sprioc-FPS réamhshocraithe nuair atá sé cumasaithe. |
| `fps` |  | number | no | `24` | 1 – 60 | Ráta fráma an fhíseáin aschuir, arna thomhas i bhfrámaí in aghaidh an tsoicind. |
| `num_inference_steps` |  | integer | no | `40` | 8 – 50 | Líon na gcéimeanna tátail a rinneadh. |
| `video_cfg_scale` |  | number | no | `3` | 1 – 20 | Socrú treorach físeáin: ardaigh é le haghaidh comhsheasmhacht agus fócas níos fearr san ábhar ginte. Úsáideann sé treoir saor ó aicmitheoir (CFG). |
| `video_stg_scale` |  | number | no | `0` | 0 – 20 | Rialú ar chomhleanúnachas agus fhócas an fhíseáin trí scála na Treorach Spásamaithí (STG); méadaigh an socrú chun an dá cháilíocht a neartú. |
| `video_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Coigeartú athscálaithe físeáin chun treoir saor ó aicmitheoir agus treoir spásamaithí a chothromú mar chóimheas. |
| `video_modality_scale` |  | number | no | `3` | 0 – 10 | Coigeartú módúlachta físeáin chun rannchuidithe físeáin agus fuaime a chothromú mar chóimheas. |
| `audio_cfg_scale` |  | number | no | `7` | 1 – 20 | Socrú treorach fuaime: ardaigh é le haghaidh comhsheasmhacht agus fócas níos fearr san ábhar ginte. Úsáideann sé treoir saor ó aicmitheoir (CFG). |
| `audio_stg_scale` |  | number | no | `0` | 0 – 20 | Rialú ar chomhleanúnachas agus fhócas na fuaime trí scála na Treorach Spásamaithí (STG); méadaigh an socrú chun an dá cháilíocht a neartú. |
| `audio_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Coigeartú athscálaithe fuaime chun treoir saor ó aicmitheoir agus treoir spásamaithí a chothromú mar chóimheas. |
| `audio_modality_scale` |  | number | no | `3` | 0 – 10 | Coigeartú módúlachta fuaime chun rannchuidithe físeáin agus fuaime a chothromú mar chóimheas. |
| `gradient_estimation_gamma` |  | number | no | `2` | 0 – 10 | Socrú meastacháin grádáin dí-ruaíochta: múchann 0 an meastachán; murach sin, sonraíonn an luach gáma. |
| `use_restart_sampling` |  | boolean | no | `false` |  | Scorán samplála atosaithe le haghaidh caighdeán físeáin a d’fhéadfadh a bheith níos fearr: má chumasaítear é, cuirtear beagán torainn leis ag gach céim dí-ruaíochta. |
| `scheduler` |  | enum (string) | no | `ltx2` | `ltx2`, `linear_quadratic`, `beta` | Roghnú sceidealóra. |
| `acceleration` |  | enum (string) | no | `regular` | `none`, `regular`, `high`, `full` | Leibhéal luasghéaraithe a chuirtear i bhfeidhm ar phróiseáil. |
| `camera_lora` |  | enum (string) | no | `none` | `dolly_in`, `dolly_out`, `dolly_left`, `dolly_right`, `jib_up`, `jib_down`, `static`, `none` | Roghnú Camera LoRA chun gluaiseacht san fhíseán ginte a rialú níos cruinne ná leideanna gluaisne ceamara amháin. |
| `camera_lora_scale` |  | number | no | `1` | 0 – 1 | Neart Camera LoRA chun gluaiseacht san fhíseán ginte a rialú níos cruinne ná leideanna gluaisne ceamara amháin. |
| `negative_prompt` |  | string | no | `news broadcast, 3d animation, computer graphics, pc game, console game, video game, cartoon, childish, watermark, logo, text, on screen text, subtitles, titles, signature, slowmo, static` |  | Leid dhiúltach a úsáidtear le linn giniúint físeáin. |
| `seed` |  | integer \| null | no |  |  | Luach síl a thosaíonn giniúint uimhreacha randamacha. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Rialaíonn sé an bhfuil leathnú na leide cumasaithe. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Rialaíonn sé an bhfuil seiceáil sábháilteachta cumasaithe. |
| `video_output_type` |  | enum (string) | no | `X264 (.mp4)` | `X264 (.mp4)`, `VP9 (.webm)`, `PRORES4444 (.mov)`, `GIF (.gif)` | Cineál aschuir an fhíseáin a bheidh mar thoradh air. |
| `video_quality` |  | enum (string) | no | `high` | `low`, `medium`, `high`, `maximum` | Leibhéal cáilíochta an fhíseáin a bheidh mar thoradh air. |
| `video_write_mode` |  | enum (string) | no | `balanced` | `fast`, `balanced`, `small` | Mód scríofa an fhíseáin a bheidh mar thoradh air. |
| `distill_lora_first_pass_scale` |  | number | no | `0.2` | 0 – 1 | Rialaigh scálú LoRA driogtha an chéad phas, agus úsáid 0 chun é a mhúchadh. |
| `distill_lora_second_pass_scale` |  | number | no | `0.5` | 0 – 1 | Rialaigh scálú LoRA driogtha do gach pas tar éis an chéad cheann. |
| `extend_direction` |  | enum (string) | no | `forward` | `forward`, `backward` | An taobh den fhíseán le leathnú: roghnaigh 'backward' chun ábhar a chur leis roimh a thús nó 'forward' chun ábhar a chur leis tar éis a dheiridh. |
| `num_context_frames` |  | integer | no | `25` | 0 – 121 | Comhaireamh frámaí a úsáidtear chun comhthéacs a sholáthar agus an físeán á leathnú. |
| `video_strength` |  | number | no | `1` | 0 – 1 | Rialaíonn an neart riochtaithe seo an tsaoirse chun ábhar an fhíseáin a athrú: tugann socruithe níos lú níos mó saoirse don tsamhail. |
| `audio_strength` |  | number | no | `1` | 0 – 1 | Rialaíonn an neart riochtaithe seo an tsaoirse chun ábhar na fuaime a athrú: tugann socruithe níos lú níos mó saoirse don tsamhail. |
| `end_image_strength` |  | number | no | `1` | 0 – 1 | Rialaigh cé mhéad a imríonn an íomhá deiridh tionchar ar an bhfíseán ginte. |

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

A fuller example:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "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.com/v1/run/ltx-2.3-22b/extend-video?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "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.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/ltx-2.3-22b/extend-video?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "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.com/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "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/ltx-2.3-22b/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.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": "ltx-2.3-22b/extend-video",
      "input": {
        "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
        "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": "ltx-2.3-22b/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": 180,
    "usd": "0.18",
    "charged": 180,
    "refunded": 0
  },
  "input": {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4"
  },
  "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
    },
    "seed": 42,
    "prompt": "A woman stands still amid a busy neon-lit street at night. The camera slowly dollies in toward her face as people blur past, their motion emphasizing her calm presence. City lights flicker and reflections shift across her denim jacket."
  },
  "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.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.com/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} | An físeán a tháirg an tsamhail. |
| `seed` | integer | Luach síl a úsáidtear chun giniúint uimhreacha randamacha a thúsú. |
| `prompt` | string | Leid a úsáidtear chun giniúint a threorú. |

## Related models

- [LTX-2.3 22B · Text to Video](https://doitong.com/developers/models/ltx-2.3-22b/text-to-video.md) (`ltx-2.3-22b/text-to-video`): $0.00161 / megapixel of output video
- [LTX-2.3 22B · Text to Video · LoRA](https://doitong.com/developers/models/ltx-2.3-22b/text-to-video/lora.md) (`ltx-2.3-22b/text-to-video/lora`): $0.00181 / megapixel of output video
- [LTX-2.3 22B · Image to Video](https://doitong.com/developers/models/ltx-2.3-22b/image-to-video.md) (`ltx-2.3-22b/image-to-video`): $0.00161 / megapixel of output video
- [LTX-2.3 22B · Image to Video · LoRA](https://doitong.com/developers/models/ltx-2.3-22b/image-to-video/lora.md) (`ltx-2.3-22b/image-to-video/lora`): $0.00181 / megapixel of output video
- [LTX 2.3 22B](https://doitong.com/developers/models/ltx-2.3-22b/reference-video-to-video/lora.md) (`ltx-2.3-22b/reference-video-to-video/lora`): $0.00181 / megapixel of output video
- [LTX-2.3 22B · Extend Video · LoRA](https://doitong.com/developers/models/ltx-2.3-22b/extend-video/lora.md) (`ltx-2.3-22b/extend-video/lora`): $0.00181 / megapixel of output video
- [LTX-2.3 22B · Reference Video to Video](https://doitong.com/developers/models/ltx-2.3-22b/reference-video-to-video.md) (`ltx-2.3-22b/reference-video-to-video`): $0.00161 / megapixel of output video
- [LTX-2.3 22B · Video to Video](https://doitong.com/developers/models/ltx-2.3-22b/video-to-video.md) (`ltx-2.3-22b/video-to-video`): $0.00161 / megapixel of output video

## Links

- HTML page: https://doitong.com/developers/models/ltx-2.3-22b/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=ltx-2.3-22b/extend-video
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/ltx-2.3-22b/extend-video