# LTX-2.3 22B · Extend Video API

> Ka haere tonu i tētahi ataata kē mai i tētahi aki, me te oro hangaia me tētahi whakaahua whakamutunga kōwhiringa

Ka tango i `video_url` me `prompt`, ka waihanga i te haere tonutanga o `num_frames` tāpare (9 ki te 481). Mā `end_image_url` kōwhiringa e tautuhi te wāhi ka mutu te toronga. Mā `match_input_fps` e mau ai te auau tāpare pūtake, mā `generate_audio` e tāpiri te oro, ā, ko te taunoa o `video_size` he auto. Ka taea te putanga hei mp4, webm, mov, GIF rānei.

- 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/mi/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 |  |  | Tohutohu ka whakamahia hei pūtake mō te whakaputanga ataata. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL e tohu ana ki te ataata ka whakawhānuitia. |
| `end_image_url` | `end_image` | string (image URL) \| null | no |  |  | Tukua he atahanga anga-mutunga mā te URL hei tautuhi i te mutunga o te ataata kua whakawhānuitia. |
| `num_frames` |  | integer | no | `121` | 9 – 481 | Tau anga mō te putanga kua whakaputaina. |
| `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` | Ngā ahunga o te ataata kua whakaputaina. |
| `generate_audio` |  | boolean | no | `true` |  | Ka whakahaere mēnā he ororongo kua whakaputaina kei roto i te ataata. |
| `use_multiscale` |  | boolean | no | `true` |  | Whakakā whakaputanga tauine-maha mō te pai ake o te hononga me te taipitopito. Ina True, mā tētahi ataata iti ake o mua e ārahi te whakaputanga tuarua, ko tōna rahi ka rite, ka nui ake rānei i ngā āhuatanga i tonoa. |
| `match_input_fps` |  | boolean | no | `true` |  | Whakakapi tere anga putanga ka whakakapi i te FPS whāinga taunoa ki te FPS o te ataata pūtake ina whakakāhia. |
| `fps` |  | number | no | `24` | 1 – 60 | Tere anga ataata putanga, kua inea ki ngā anga ia hēkona. |
| `num_inference_steps` |  | integer | no | `40` | 8 – 50 | Tatau o ngā takahanga inference i mahia. |
| `video_cfg_scale` |  | number | no | `3` | 1 – 20 | Tautuhinga ārahi ataata: whakanuia kia nui ake te ōritetanga me te aronga o ngā ihirangi kua whakaputaina. Ka whakamahi i te ārahi classifier-free (CFG). |
| `video_stg_scale` |  | number | no | `0` | 0 – 20 | Whakahaere i te ōritetanga me te aronga o te ataata mā te tauine Spatiotemporal Guidance (STG); whakanuia te tautuhinga kia kaha ake ai ēnei āhuatanga e rua. |
| `video_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Whakarerekētanga tauine anō o te ataata hei taurite i te ārahi classifier-free ki te ārahi mokowā-wā, hei ōwehenga. |
| `video_modality_scale` |  | number | no | `3` | 0 – 10 | Whakarerekētanga aratau ataata hei taurite i ngā takoha ataata me te ororongo, hei ōwehenga. |
| `audio_cfg_scale` |  | number | no | `7` | 1 – 20 | Tautuhinga ārahi ororongo: whakanuia kia nui ake te ōritetanga me te aronga o ngā ihirangi kua whakaputaina. Ka whakamahi i te ārahi classifier-free (CFG). |
| `audio_stg_scale` |  | number | no | `0` | 0 – 20 | Whakahaere i te ōritetanga me te aronga o te ororongo mā te tauine Spatiotemporal Guidance (STG); whakanuia te tautuhinga kia kaha ake ai ēnei āhuatanga e rua. |
| `audio_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Whakarerekētanga tauine anō o te ororongo hei taurite i te ārahi classifier-free ki te ārahi mokowā-wā, hei ōwehenga. |
| `audio_modality_scale` |  | number | no | `3` | 0 – 10 | Whakarerekētanga aratau ororongo hei taurite i ngā takoha ataata me te ororongo, hei ōwehenga. |
| `gradient_estimation_gamma` |  | number | no | `2` | 0 – 10 | Tautuhinga whakatau-taumata gradient denoising: mā te 0 ka whakawetohia te whakatau; ki te kore, ka tohu te uara i te gamma. |
| `use_restart_sampling` |  | boolean | no | `false` |  | Whakakā tīmata anō i te sampling mō te kounga ataata pai ake pea: mā te whakakā ka tāpirihia he haruru iti i ia hīkoi denoising. |
| `scheduler` |  | enum (string) | no | `ltx2` | `ltx2`, `linear_quadratic`, `beta` | Kōwhiringa scheduler. |
| `acceleration` |  | enum (string) | no | `regular` | `none`, `regular`, `high`, `full` | Taumata whakatere i whakamahia mō te tukatuka. |
| `camera_lora` |  | enum (string) | no | `none` | `dolly_in`, `dolly_out`, `dolly_left`, `dolly_right`, `jib_up`, `jib_down`, `static`, `none` | Kōwhiringa Camera LoRA hei whakahaere tika ake i te nekehanga o te ataata kua whakaputaina i ngā tohutohu nekehanga-kamera anake. |
| `camera_lora_scale` |  | number | no | `1` | 0 – 1 | Te kaha Camera LoRA hei whakahaere tika ake i te nekehanga o te ataata kua whakaputaina i ngā tohutohu nekehanga-kamera anake. |
| `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` |  | Tohutohu tōraro ka whakamahia i te whakaputanga ataata. |
| `seed` |  | integer \| null | no |  |  | Uara kākano hei tīmata i te whakaputanga tau matapōkere. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Ka whakahaere mēnā kua whakahohea te whakawhānui tohutohu. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Ka whakahaere mēnā kua whakakāhia te tirotiro haumaru. |
| `video_output_type` |  | enum (string) | no | `X264 (.mp4)` | `X264 (.mp4)`, `VP9 (.webm)`, `PRORES4444 (.mov)`, `GIF (.gif)` | Momo putanga mō te ataata ka puta. |
| `video_quality` |  | enum (string) | no | `high` | `low`, `medium`, `high`, `maximum` | Taumata kounga mō te ataata ka puta. |
| `video_write_mode` |  | enum (string) | no | `balanced` | `fast`, `balanced`, `small` | Aratau tuhi mō te ataata ka puta. |
| `distill_lora_first_pass_scale` |  | number | no | `0.2` | 0 – 1 | Whakahaerehia te tauine distill LoRA o te whakawhitinga tuatahi; whakamahia te 0 hei whakaweto. |
| `distill_lora_second_pass_scale` |  | number | no | `0.5` | 0 – 1 | Whakahaerehia te tauine distill LoRA mō ia whakawhitinga i muri i te tuatahi. |
| `extend_direction` |  | enum (string) | no | `forward` | `forward`, `backward` | Taha o te ataata hei whakawhānui: kōwhiria 'backward' hei tāpiri ihirangi i mua i te tīmatanga, 'forward' rānei hei tāpiri ihirangi i muri i te mutunga. |
| `num_context_frames` |  | integer | no | `25` | 0 – 121 | Tatau anga ka whakamahia hei whakarato horopaki i te whakawhānuitanga ataata. |
| `video_strength` |  | number | no | `1` | 0 – 1 | Ka whakahaere tēnei kaha conditioning i te wātea ki te whakarerekē i ngā ihirangi ataata: mā ngā tautuhinga iti ka nui ake te wātea o te tauira. |
| `audio_strength` |  | number | no | `1` | 0 – 1 | Ka whakahaere tēnei kaha conditioning i te wātea ki te whakarerekē i ngā ihirangi ororongo: mā ngā tautuhinga iti ka nui ake te wātea o te tauira. |
| `end_image_strength` |  | number | no | `1` | 0 – 1 | Whakahaerehia te nui o te awe o te atahanga mutunga ki te ataata kua whakaputaina. |

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} | Ataata i whakaputaina e te tauira. |
| `seed` | integer | Uara seed hei tīmata i te whakaputanga tau matapōkere. |
| `prompt` | string | Tohutohu hei ārahi i te whakaputanga. |

## 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