# LTX-2.3 22B · Extend Video API

> A’ leantainn bhidio a th’ ann bho prompt, le fuaim air a ghineadh agus dealbh roghainneil aig an deireadh

A’ gabhail `video_url` agus `prompt` agus a’ gineadh leantainn de `num_frames` frèam (9 gu 481). Bidh `end_image_url` roghainneil a’ suidheachadh far a bheil an leudachadh a’ crìochnachadh. Bidh `match_input_fps` a’ cumail ìre frèam an tùs, bidh `generate_audio` a’ cur fuaim ris, agus tha `video_size` auto mar bhun-roghainn. Faodaidh an toradh a bhith mp4, webm, mov no 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/gd/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 |  |  | Prompt a chaidh a chleachdadh mar bhunait airson gineadh bhidio. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL a chomharraicheas am bhidio a thèid a leudachadh. |
| `end_image_url` | `end_image` | string (image URL) \| null | no |  |  | Thoir seachad ìomhaigh an fhrèam dheireannaich tro URL gus mìneachadh mar a thig am bhidio leudaichte gu crìch. |
| `num_frames` |  | integer | no | `121` | 9 – 481 | Àireamh fhrèamaichean airson an às-chuir a chaidh a chruthachadh. |
| `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` | Meudan a’ bhidio a chaidh a ghineadh. |
| `generate_audio` |  | boolean | no | `true` |  | A’ cumail smachd air a bheil claisneachd gineadh anns a’ bhidio. |
| `use_multiscale` |  | boolean | no | `true` |  | Toglaich gineadh ioma-sgèile airson co-leanailteachd agus mion-fhiosrachadh nas fheàrr. Le True, bidh bhidio tòiseachaidh nas lugha a’ stiùireadh dàrna gineadh aig a bheil meud co-ionann no nas motha na na tomhasan a chaidh iarraidh. |
| `match_input_fps` |  | boolean | no | `true` |  | Tar-sgrìobhadh ìre-frèam an às-chuir a chuireas FPS bhidio an tùsail an àite an FPS targaid bun-roghainn nuair a tha e an comas. |
| `fps` |  | number | no | `24` | 1 – 60 | Ìre frèam bhidio an às-chuir, air a tomhas ann am frèaman san diog. |
| `num_inference_steps` |  | integer | no | `40` | 8 – 50 | Àireamh nan ceumannan inference a chaidh a choileanadh. |
| `video_cfg_scale` |  | number | no | `3` | 1 – 20 | Suidheachadh stiùiridh bhidio: àrdaich e airson barrachd co-sheasmhachd agus fòcas san t-susbaint a chaidh a ghineadh. A’ cleachdadh classifier-free guidance (CFG). |
| `video_stg_scale` |  | number | no | `0` | 0 – 20 | Smachd air co-sheasmhachd agus fòcas a’ bhidio tro sgèile Spatiotemporal Guidance (STG); àrdaich an suidheachadh gus an dà chuid a neartachadh. |
| `video_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Atharrachadh ath-sgèileachaidh bhidio airson classifier-free agus stiùireadh spatiotemporal a chothromachadh mar cho-mheas. |
| `video_modality_scale` |  | number | no | `3` | 0 – 10 | Atharrachadh modhalachd bhidio airson tabhartasan a’ bhidio agus na claisneachd a chothromachadh mar cho-mheas. |
| `audio_cfg_scale` |  | number | no | `7` | 1 – 20 | Suidheachadh stiùiridh claisneachd: àrdaich e airson barrachd co-sheasmhachd agus fòcas san t-susbaint a chaidh a ghineadh. A’ cleachdadh classifier-free guidance (CFG). |
| `audio_stg_scale` |  | number | no | `0` | 0 – 20 | Smachd air co-sheasmhachd agus fòcas na claisneachd tro sgèile Spatiotemporal Guidance (STG); àrdaich an suidheachadh gus an dà chuid a neartachadh. |
| `audio_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Atharrachadh ath-sgèileachaidh claisneachd airson classifier-free agus stiùireadh spatiotemporal a chothromachadh mar cho-mheas. |
| `audio_modality_scale` |  | number | no | `3` | 0 – 10 | Atharrachadh modhalachd claisneachd airson tabhartasan a’ bhidio agus na claisneachd a chothromachadh mar cho-mheas. |
| `gradient_estimation_gamma` |  | number | no | `2` | 0 – 10 | Suidheachadh tuairmseachaidh caisead dì-fhuaimneachaidh: bidh 0 a’ cur an tuairmseachadh dheth; air neo, sònraichidh an luach gamma. |
| `use_restart_sampling` |  | boolean | no | `false` |  | Toglaich samplachadh ath-thòiseachaidh airson càileachd bhidio a dh’fhaodadh a bhith nas fheàrr: le bhith ga chur an comas, thèid beagan fuaim a chur ris aig gach ceum dì-fhuaimneachaidh. |
| `scheduler` |  | enum (string) | no | `ltx2` | `ltx2`, `linear_quadratic`, `beta` | Taghadh scheduler. |
| `acceleration` |  | enum (string) | no | `regular` | `none`, `regular`, `high`, `full` | Ìre luathachaidh air a cur an sàs ann an giullachd. |
| `camera_lora` |  | enum (string) | no | `none` | `dolly_in`, `dolly_out`, `dolly_left`, `dolly_right`, `jib_up`, `jib_down`, `static`, `none` | Taghadh Camera LoRA airson smachd nas mionaidiche air gluasad sa bhidio a chaidh a ghineadh na tha comasach le promptan gluasad-camara leotha fhèin. |
| `camera_lora_scale` |  | number | no | `1` | 0 – 1 | Neart Camera LoRA airson smachd nas mionaidiche air gluasad sa bhidio a chaidh a ghineadh na tha comasach le promptan gluasad-camara leotha fhèin. |
| `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` |  | Prompt àicheil a thèid a chleachdadh rè gineadh bhidio. |
| `seed` |  | integer \| null | no |  |  | Luach sìl a thòisicheas gineadh àireamhan air thuaiream. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Smachd air a bheil leudachadh a’ phrompt air a chomasachadh. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Smachd air co-dhiù a bheil sgrùdadh sàbhailteachd air a chomasachadh. |
| `video_output_type` |  | enum (string) | no | `X264 (.mp4)` | `X264 (.mp4)`, `VP9 (.webm)`, `PRORES4444 (.mov)`, `GIF (.gif)` | Seòrsa às-chuir airson a’ bhidio a thig às. |
| `video_quality` |  | enum (string) | no | `high` | `low`, `medium`, `high`, `maximum` | Ìre càileachd airson a’ bhidio a thig às. |
| `video_write_mode` |  | enum (string) | no | `balanced` | `fast`, `balanced`, `small` | Modh sgrìobhaidh airson a’ bhidio a thig às. |
| `distill_lora_first_pass_scale` |  | number | no | `0.2` | 0 – 1 | Smachd air sgèileadh distill LoRA a’ chiad phas, a’ cleachdadh 0 airson a chur dheth. |
| `distill_lora_second_pass_scale` |  | number | no | `0.5` | 0 – 1 | Smachd air sgèileadh distill LoRA airson gach pas às dèidh a’ chiad phas. |
| `extend_direction` |  | enum (string) | no | `forward` | `forward`, `backward` | Taobh a’ bhidio ri leudachadh: tagh 'backward' gus susbaint a chur ris ron toiseach no 'forward' gus susbaint a chur ris às dèidh a’ chrìche. |
| `num_context_frames` |  | integer | no | `25` | 0 – 121 | Àireamh nam frèaman a thèid a chleachdadh gus co-theacsa a thoirt seachad nuair a thathar a’ leudachadh a’ bhidio. |
| `video_strength` |  | number | no | `1` | 0 – 1 | Tha saorsa atharrachadh susbaint a’ bhidio fo smachd an neirt conditionachaidh seo: leigidh suidheachaidhean nas lugha barrachd saorsa leis a’ mhodail. |
| `audio_strength` |  | number | no | `1` | 0 – 1 | Tha saorsa atharrachadh susbaint na claisneachd fo smachd an neirt conditionachaidh seo: leigidh suidheachaidhean nas lugha barrachd saorsa leis a’ mhodail. |
| `end_image_strength` |  | number | no | `1` | 0 – 1 | Cum smachd air na tha an ìomhaigh dheireannaich a’ toirt buaidh air a’ bhidio a chaidh a ghineadh. |

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} | Bhidio a rinn am modail. |
| `seed` | integer | Luach seed a thèid a chleachdadh gus gineadh àireamhan air thuaiream a thòiseachadh. |
| `prompt` | string | Prompt a thèid a chleachdadh gus gineadh a stiùireadh. |

## 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