# LTX-2.3 22B · Extend Video API

> Joatká dálá video prompta vuođul, ráhkaduvvon jienain ja vejolaš maŋemusgovain

Geavaha `video_url` ja `prompt` ja ráhkada `num_frames` rámmá (9 rájes 481 rádjái) joatkka. Vejolaš `end_image_url` mearrida gos joatkka loahpá. `match_input_fps` seailluha gáldo-rámmeláhti, `generate_audio` lasiha jiena, ja `video_size` lea standárdan auto. Bohtos sáhttá leat mp4, webm, mov dahje 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/se/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 |  |  | Bivdda, mii geavahuvvo video-ráhkadeami vuođđun. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL mii čujuha videoi mii galgá guhkkiduvvot. |
| `end_image_url` | `end_image` | string (image URL) \| null | no |  |  | Addi loahpparámma-govaga URL:n meroštallat mo guhkkiduvvon video loahpá. |
| `num_frames` |  | integer | no | `121` | 9 – 481 | Ráhkaduvvon boađusa rámma-lohku. |
| `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` | Ráhkaduvvon video dimensuvnnat. |
| `generate_audio` |  | boolean | no | `true` |  | Stivre, leatgo ráhkaduvvon jietna videoráhkadeamis. |
| `use_multiscale` |  | boolean | no | `true` |  | Máŋgga-skála ráhkadeami molssaeapmi buoret oktavuođa ja biena várás. True:s vuosttaš unnit video stivre nubbi ráhkadeami, man sturrodat lea seamma stuoris dahje stuorát go jearahuvvon dimenšuvnnat. |
| `match_input_fps` |  | boolean | no | `true` |  | Boađus-rámma-frekveansa buhtten mii aktiverejuvvon buhttá standárda FPS:a gáldo-video FPS:ain. |
| `fps` |  | number | no | `24` | 1 – 60 | Boađusvideo rámmafrekveansa, rámman sekundas. |
| `num_inference_steps` |  | integer | no | `40` | 8 – 50 | Dahkkojuvvon inferensa-ceahpeloahppa. |
| `video_cfg_scale` |  | number | no | `3` | 1 – 20 | Video-stivrejeaddji heivehus: lasit dan buoret ovttastallama ja fokusa várás ráhkaduvvon sisdoalus. Geavaha classifier-free guidance (CFG). |
| `video_stg_scale` |  | number | no | `0` | 0 – 20 | Video-ovttastallama ja fokusa stivren Spatiotemporal Guidance (STG)-skálain; lasit heivehusa nannet goappaš dáid kvalitehtaid. |
| `video_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Video-reskálerejeaddji heivehus mii dávista classifier-free ja spatiotemporal guidance:a gaskasa ratio:n. |
| `video_modality_scale` |  | number | no | `3` | 0 – 10 | Video-modálitehta heivehus mii dávista video ja jietnaga váikkuhusaid ratio:n. |
| `audio_cfg_scale` |  | number | no | `7` | 1 – 20 | Jietnaga stivrejeaddji heivehus: lasit dan buoret ovttastallama ja fokusa várás ráhkaduvvon sisdoalus. Geavaha classifier-free guidance (CFG). |
| `audio_stg_scale` |  | number | no | `0` | 0 – 20 | Jietnaga ovttastallama ja fokusa stivren Spatiotemporal Guidance (STG)-skálain; lasit heivehusa nannet goappaš dáid kvalitehtaid. |
| `audio_rescaling_scale` |  | number | no | `0.7` | 0 – 1 | Jietnaga reskálerejeaddji heivehus mii dávista classifier-free ja spatiotemporal guidance:a gaskasa ratio:n. |
| `audio_modality_scale` |  | number | no | `3` | 0 – 10 | Jietnaga modálitehta heivehus mii dávista video ja jietnaga váikkuhusaid ratio:n. |
| `gradient_estimation_gamma` |  | number | no | `2` | 0 – 10 | Denoising-gradienta árvvoštallama heivehus: 0 čuohcá árvvoštallama eret; muđui árvu meroštallá gamma. |
| `use_restart_sampling` |  | boolean | no | `false` |  | Ođđasit-samplinga molssaeapmi vejolaš buoret video-kvalitehta várás: aktivereapmi lasiha veaháš jietnaduođa juohke denoising-ceahkis. |
| `scheduler` |  | enum (string) | no | `ltx2` | `ltx2`, `linear_quadratic`, `beta` | Scheduler-válljen. |
| `acceleration` |  | enum (string) | no | `regular` | `none`, `regular`, `high`, `full` | Gieđahallamii geavahuvvon áhtanivla. |
| `camera_lora` |  | enum (string) | no | `none` | `dolly_in`, `dolly_out`, `dolly_left`, `dolly_right`, `jib_up`, `jib_down`, `static`, `none` | Kamera LoRA-válljen mii stivre ráhkaduvvon video lihkadeami dárkilut go kamera-lihkadeami bivddat ok alone. |
| `camera_lora_scale` |  | number | no | `1` | 0 – 1 | Kamera LoRA nanusvuohta mii stivre ráhkaduvvon video lihkadeami dárkilut go kamera-lihkadeami bivddat ok alone. |
| `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` |  | Negatiiva bivdda maid geavahuvvo video ráhkadeamis. |
| `seed` |  | integer \| null | no |  |  | Seed-árvu, mii álggaha sattumlohkoráhkadeami. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Stivre leago bivdda viiddideapmi anus. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Stivre bealuštaniskkadeami doaibmama. |
| `video_output_type` |  | enum (string) | no | `X264 (.mp4)` | `X264 (.mp4)`, `VP9 (.webm)`, `PRORES4444 (.mov)`, `GIF (.gif)` | Boađusvideo šládja. |
| `video_quality` |  | enum (string) | no | `high` | `low`, `medium`, `high`, `maximum` | Boađusvideo kvalitehtadássi. |
| `video_write_mode` |  | enum (string) | no | `balanced` | `fast`, `balanced`, `small` | Boađusvideo čájehanvuohki. |
| `distill_lora_first_pass_scale` |  | number | no | `0.2` | 0 – 1 | Stivre vuosttaš passa distill LoRA-skálema, ja geavat 0 dan čuohčat eret. |
| `distill_lora_second_pass_scale` |  | number | no | `0.5` | 0 – 1 | Stivre distill LoRA-skálema juohke passa várás vuosttaš passa maŋŋá. |
| `extend_direction` |  | enum (string) | no | `forward` | `forward`, `backward` | Video bealli maid guhkkidat: vállje 'backward' lasihit sisdoalu ovdal álggu dahje 'forward' lasihit sisdoalu loahpa maŋŋá. |
| `num_context_frames` |  | integer | no | `25` | 0 – 121 | Rámma-lohku mii geavahuvvo kontekstii video guhkkideamis. |
| `video_strength` |  | number | no | `1` | 0 – 1 | Dát kondišunerema nanusvuohta stivre friddjavuođa rievdadit video sisdoalu: unnit heivehusat addet modeallii eanet friddjavuođa. |
| `audio_strength` |  | number | no | `1` | 0 – 1 | Dát kondišunerema nanusvuohta stivre friddjavuođa rievdadit jietnaga sisdoalu: unnit heivehusat addet modeallii eanet friddjavuođa. |
| `end_image_strength` |  | number | no | `1` | 0 – 1 | Stivre man olu loahppagovva váikkuha ráhkaduvvon videui. |

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} | Modealla ráhkadan video. |
| `seed` | integer | Sivaárvu mii geavahuvvo random-logu ráhkadeami álggahallamii. |
| `prompt` | string | Bivdda mii stivre ráhkadeami. |

## 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