# Ltx 2.3 Quality · Reference Video to Video API

> Beiðnistýrð myndun samkvæmt viðmiðunarmyndskeiði, með valfrjálsum myndum af fyrsta, mið- og síðasta lykilramma

Býr til nýtt myndskeið úr nauðsynlegu `prompt` og viðmiðunar-`video_url` sem leggur til hreyfingu og uppbyggingu. Valfrjálst `image_url`, `mid_image_url` og `end_image_url` festa útlitið í upphafi, miðju og lokum. `video_strength` og `strength` (bæði 0 to 1) stjórna því hversu náið úttakið fylgir eða varðveitir upprunann, og `control_video_url` getur lagt til fyrirfram útreiknað stýrimerki. `resolution` býður upp á sjálfvirkar eða fastar forstillingar á borð við ferning og 16:9 lóðrétt eða lárétt.

- Model id: `ltx-2.3-quality/reference-video-to-video`
- Made by: Lightricks
- Category: Video to Video
- Output: video
- Price per megapixel of your output video: $0.00241 / megapixel of output video (cheapest run $0.003 (3 API credits))
- Run: `POST https://api.doitong.ru/v1/run/ltx-2.3-quality/reference-video-to-video`
- Quote: `POST https://api.doitong.ru/v1/quote/ltx-2.3-quality/reference-video-to-video`
- Docs page: https://doitong.com/is/developers/models/ltx-2.3-quality/reference-video-to-video

## Pricing

Price: **$0.00241 / 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 $0.27 = 270 API credits (112 MP output video × $0.002408).

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/ltx-2.3-quality/reference-video-to-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 |  |  | Kvaðning notuð til að stýra efnisgerð. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL sem vísar á viðmiðunarmyndband sem notað er til að leiðbeina hreyfingu og uppbyggingu. |
| `control_video_url` |  | string (video URL) \| null | no |  |  | Valfrjálst fyrirframreiknað stýrimyndband, notað í stað innbyggðs stýriútreiknings þegar það er gefið upp ásamt `skip_control_preprocess`. Það verður beint stýrimerki eftir endursýnatöku til að samræma úttaksvíddir og rammatölu. Myndbandið getur til dæmis innihaldið tilbúið dýptar-, brúnar- eða stellingasamsetta mynd. |
| `skip_control_preprocess` |  | boolean | no | `false` |  | Bein stýring með `control_video_url` í stað þess að áætla dýpt, brúnir eða stellingu innbyrðis; án þess URL er þessi stilling hunsuð. Stærðarstilling í þessum ham virðir nákvæmar víddir með 64-samræmingu svo RGB- og stýrimyndbönd passi saman, en `auto` tekur víddir og stærðarhlutfall upprunans innan LTX-takmarka. |
| `preserve_original_video` |  | boolean | no | `false` |  | Hamur til að varðveita upprunalegt myndband, aðeins í boði með `skip_control_preprocess`, `video_url` og `control_video_url`. Hann er sjálfgefið óvirkur og heldur hefðbundinni stýrivinnslu óbreyttri; þegar hann er virkjaður hefst efnisgerð frá `video_url` en uppbyggingarleiðsögn frá `control_video_url` er varðveitt. Afmyndun með `strength` stillir hversu mikið er varðveitt; lægri gildi varðveita fleiri upprunalega pixla. |
| `image_url` | `image` | string (image URL) \| null | no |  |  | Valfrjáls stíll fyrir myndfestingu eða auðkenni persónu sem lykilrammi fyrsta ramma. |
| `mid_image_url` |  | string (image URL) \| null | no |  |  | Valfrjálst útlit fyrir myndfestingu nálægt miðju myndbandsins, sem bætir við upphaflega `image_url`-lykilrammann. Það hjálpar útlitinu að fylgja hreyfingu myndavélarinnar í stað þess að færast til; krefst `image_url`. |
| `end_image_url` | `end_image` | string (image URL) \| null | no |  |  | Valfrjálst útlit fyrir myndfestingu við síðasta ramma myndbandsins. Gagnlegt þegar hreyfing myndavélarinnar endar á öðrum stað en upphafsmyndin; krefst `image_url`. |
| `video_strength` |  | number | no | `0.6` | 0 – 1 | Þessi skilyrðisstyrkur stjórnar frelsi til að breyta hreyfingu og uppbyggingu úr viðmiðunarmyndbandinu: lægri gildi leyfa meiri breytingar. |
| `strength` |  | number | no | `1` | 0 – 1 | Stýring afmyndunar fyrir sýnatöku frá viðmiðunarmyndbandi yfir í myndband, en áhrifin ráðast af `preserve_original_video`. Þegar hamurinn er óvirkur styttir hún aðeins afmyndunaráætlunina; þegar hann er virkur stjórnar hún umbreytingu upprunapixla. Gildið 1.0 endurgerir allt en lægri gildi varðveita meira, til dæmis varðveitir 0.5 um 50%. |
| `num_frames` |  | integer | no | `121` | 9 – 481 | Fjöldi úttaksramma, háður IC-LoRA-stöðugleikafjárhagsramma sem byggist á upplausn margfaldaðri með römmum. Svar 422 merkir að farið var yfir fjárhagsrammann: lækkaðu upplausnina eða `num_frames`. Fjárhagsramminn leyfir um það bil 150 ramma við 720p-líkar víddir og fleiri við minni stærðir. |
| `resolution` |  | object {width, height} \| enum (string) | no | `auto` | `auto`, `square_hd`, `square`, `portrait_4_3`, `portrait_16_9`, `landscape_4_3`, `landscape_16_9` | Víddir úttakmyndbands, sem hafa einnig áhrif á stöðuga lengd: minni stærðir leyfa fleiri römmum en stærri stærðir lækka hámarkið. Innbyggður stýriútreikningur heldur stærðinni nálægt opinberu stýriupplýsingaflæðinu; bein stýring með `skip_control_preprocess` og `control_video_url` virðir þess í stað nákvæmar víddir með 64px-samræmingu. Í beinum stýriham erfir `auto` víddir og stærðarhlutfall upprunans innan LTX-takmarka. |
| `frames_per_second` |  | number | no | `24` | 1 – 60 | Rammatíðni úttaksvídeós, mæld í römmum á sekúndu. |
| `num_inference_steps` |  | integer | no | `15` | 8 – 30 | Stilltu hversu mörg ályktunarskref eigi að keyra, allt að 30; ef þetta er óbreytt eru 15 notuð. |
| `guidance_scale` |  | number | no | `1` | 1 – 20 | Stilltu classifier-free guidance með þessum kvarða; sjálfgefin kvörðun hans miðar að bæði háum gæðum og hraðri efnisgerð. |
| `generate_audio` |  | boolean | no | `true` |  | Kveikja fyrir hljóðrás MP4-skrárinnar sem skilað er: óvirk stilling skilar myndbandsskrá án hljóðs, en virk stilling tekur hljóð með. |
| `negative_prompt` |  | string | no | `color distortion, overexposure, static, blurry details, subtitles, style, artwork, painting, frame, still, dim overall tone, worst quality, low quality, JPEG compression artifacts, ugly, mutilated, extra fingers, poorly drawn hands, poorly drawn face, deformed, disfigured, malformed limbs, fused fingers, motionless frame, cluttered background, three legs, crowded background, walking backwards` |  | Neikvæð kvaðning sem tilgreinir hverju efnisgerðin á að forðast. |
| `seed` |  | integer \| null | no |  |  | Sáðgildi sem gerir efnisgerð endurtekningarhæfa. Ef það er stillt á None er sáðgildi valið af handahófi. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Stýrir því hvort kvaðning sé útvíkkuð. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Stýrir því hvort öryggisathugun sé virk. |
| `video_quality` |  | enum (string) | no | `high` | `low`, `medium`, `high`, `maximum` | Gæðaforstilling notuð á úttaksvídeóið. |
| `video_write_mode` |  | enum (string) | no | `balanced` | `fast`, `balanced`, `small` | Skrifhamur myndbandsins sem verður til. |

File parameters (`video`, `control_video_url`, `image`, `mid_image_url`, `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.ru/v1/run/ltx-2.3-quality/reference-video-to-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.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/ltx-2.3-quality/reference-video-to-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.ru/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-quality/reference-video-to-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": "ltx-2.3-quality/reference-video-to-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-quality/reference-video-to-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": 270,
    "usd": "0.27",
    "charged": 270,
    "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
    },
    "seed": 42,
    "prompt": "string"
  },
  "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} | Myndband sem líkanið býr til. |
| `seed` | integer | Raunverulegt fræ sem notað er við efnisgerð. |
| `prompt` | string | Efnisgerðarkvaðning, þar á meðal öll útvíkkun sem er beitt áður en hún er notuð. |

## Related models

- [Ltx 2.3 Quality · Text to Video](https://doitong.com/developers/models/ltx-2.3-quality/text-to-video.md) (`ltx-2.3-quality/text-to-video`): $0.00241 / megapixel of output video
- [Ltx 2.3 Quality · Text to Video · LoRA](https://doitong.com/developers/models/ltx-2.3-quality/text-to-video/lora.md) (`ltx-2.3-quality/text-to-video/lora`): $0.00271 / megapixel of output video
- [Ltx 2.3 Quality · Image to Video](https://doitong.com/developers/models/ltx-2.3-quality/image-to-video.md) (`ltx-2.3-quality/image-to-video`): $0.00241 / megapixel of output video
- [Ltx 2.3 Quality · Image to Video · LoRA](https://doitong.com/developers/models/ltx-2.3-quality/image-to-video/lora.md) (`ltx-2.3-quality/image-to-video/lora`): $0.00271 / megapixel of output video
- [Ltx 2.3 Quality · Ingredient](https://doitong.com/developers/models/ltx-2.3-quality/ingredient.md) (`ltx-2.3-quality/ingredient`): $0.00241 / megapixel of output video
- [Ltx 2.3 Quality · Clean Plate](https://doitong.com/developers/models/ltx-2.3-quality/clean-plate.md) (`ltx-2.3-quality/clean-plate`): $0.00241 / megapixel of output video
- [Ltx 2.3 Quality · Colorization](https://doitong.com/developers/models/ltx-2.3-quality/colorization.md) (`ltx-2.3-quality/colorization`): $0.00241 / megapixel of output video
- [Ltx 2.3 Quality · Cross Eyed](https://doitong.com/developers/models/ltx-2.3-quality/cross-eyed.md) (`ltx-2.3-quality/cross-eyed`): $0.00241 / megapixel of output video

## Links

- HTML page: https://doitong.com/developers/models/ltx-2.3-quality/reference-video-to-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-quality/reference-video-to-video
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/ltx-2.3-quality/reference-video-to-video