# LTX 2.3 Trainer (V2) - Keyframe Interpolation API

> Þjálfar LoRA sem býr til hreyfingu milli fyrsta og síðasta lykilramma, valfrjálst með miðramma

Þjálfar LoRA fyrir innskot lykilramma: við keyrslu gefur þú upp fyrsta og síðasta ramma og líkanið býr til myndskeiðið þar á milli. Virkjaðu `include_middle_keyframe` til að þjálfa á fyrsta, mið- og síðasta ramma; þá verður hvert staðfestingarsýni einnig að gefa upp `middle_image_url`. Gögnin koma sem zip-safn í gegnum `training_data_url`, með allt að 2 staðfestingarfærslum.

- Model id: `ltx23-trainer-v2/interpolate`
- Made by: Lightricks
- Category: Training
- Output: file
- Price: $0.0024 / step (cheapest run $4.80 (4800 API credits))
- Run: `POST https://api.doitong.com/v1/run/ltx23-trainer-v2/interpolate`
- Quote: `POST https://api.doitong.com/v1/quote/ltx23-trainer-v2/interpolate`
- Docs page: https://doitong.com/is/developers/models/ltx23-trainer-v2/interpolate

## Pricing

Price: **$0.0024 / step**. Billed per training step (`number_of_steps`).

The full example input below costs $4.80 = 4800 API credits (2000 steps × 2.4 API credits).

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/ltx23-trainer-v2/interpolate` 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

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `training_data_url` |  | string | yes |  |  | URL á `.zip`-skrá sem inniheldur þjálfunargögn, skipulögð samkvæmt völdum þjálfunarham. Hver miðlunarskrá getur haft samsvarandi `.txt`-texta með sama grunnheiti. |
| `rank` |  | enum (integer) | no | `32` | `8`, `16`, `32`, `64`, `128` | Aðlögunarstig LoRA, þar sem aukin minnisnotkun fæst gegn meiri getu eftir því sem stillingin hækkar. |
| `number_of_steps` |  | integer | no | `2000` | 100 – 10,000 | Heildarfjöldi þjálfunarskrefa. |
| `learning_rate` |  | number | no | `0.0002` | 0.000001 – 1 | Lærhraði bestunar. |
| `number_of_frames` |  | integer | no | `89` | 9 – 121 | Fjöldi ramma í hverju þjálfunarsýni. Deiling fjöldans með 8 verður að skilja eftir afganginn 1; dæmi eru 1, 9, 17, 25, 33, 41, 49, 57, 65, 73, 81, 89, 97. |
| `frame_rate` |  | integer | no | `24` | 8 – 60 | Markrammatíðni þjálfunarmyndbands í römmum á sekúndu. Innbyggð tíðni LTX-2.3 er 24. |
| `resolution` |  | enum (string) | no | `medium` | `low`, `medium`, `high` | Þjálfunarupplausn. Hærri upplausn eykur minnisþörf. |
| `aspect_ratio` |  | enum (string) | no | `1:1` | `16:9`, `1:1`, `9:16` | Þjálfunarstærðarhlutfall. |
| `trigger_phrase` |  | string | no | `` |  | LoRA-stílvirkjunarsetning, sett fremst í texta við þjálfun. |
| `auto_scale_input` |  | boolean | no | `false` |  | Sjálfvirk aðlögun myndbands að umbeðinni FPS og rammtölu þegar hún er virk; myndgagnasöfn haldast óbreytt. |
| `split_input_into_scenes` |  | boolean | no | `true` |  | Senuskipting fyrir myndbönd sem fara yfir lengdarþröskuld, virk þegar gildið er true. |
| `split_input_duration_threshold` |  | number | no | `30` | 1 – 60 | Kveikja senuskiptingar gefin upp sem lengd í sekúndum: aðeins myndböndum sem eru lengri en þröskuldurinn er skipt. |
| `debug_dataset` |  | boolean | no | `false` |  | Skoðunarhamur forvinnslu til að yfirfara myndbönd, myndir og texta áður en full þjálfun keyrir. Þegar hann er virkur skilar þjálfarinn unnu þjálfunargagnasafni í skráasafni sem hægt er að hlaða niður til handvirkrar yfirferðar. |
| `validation` |  | array of object {prompt, start_image_url, end_image_url, middle_image_url} | no | `[]` | ≤ 2 items | Staðfestingargögn gefin upp sem listi; færsla sameinar lykilrammamyndir við kvaðningu. |
| `validation[].prompt` |  | string | yes |  |  | Kvaðning notuð við staðfestingu. |
| `validation[].start_image_url` |  | string (image URL) | yes |  | ≥ 1 characters | URL lykilrammamyndar fyrir upphafsrammann. |
| `validation[].end_image_url` |  | string (image URL) | yes |  | ≥ 1 characters | URL lykilrammamyndar fyrir lokarammann. |
| `validation[].middle_image_url` |  | string (image URL) \| null | no |  |  | URL miðlykilrammamyndar fyrir first+middle+last-milliteikningu. Keyrslur með `include_middle_keyframe=true` krefjast hennar; annars er hún valfrjáls. |
| `validation_negative_prompt` |  | string | no | `blurry, out of focus, overexposed, underexposed, low contrast, washed out colors, excessive noise, grainy texture, poor lighting, flickering, motion blur, distorted proportions, unnatural skin tones, deformed facial features, asymmetrical face, missing facial features, extra limbs, disfigured hands, wrong hand count, artifacts around text, inconsistent perspective, camera shake, incorrect depth of field, background too sharp, background clutter, distracting reflections, harsh shadows, inconsistent lighting direction, color banding, cartoonish rendering, 3D CGI look, unrealistic materials, uncanny valley effect, incorrect ethnicity, wrong gender, exaggerated expressions, wrong gaze direction, mismatched lip sync, silent or muted audio, distorted voice, robotic voice, echo, background noise, off-sync audio, incorrect dialogue, added dialogue, repetitive speech, jittery movement, awkward pauses, incorrect timing, unnatural transitions, inconsistent framing, tilted camera, flat lighting, inconsistent tone, cinematic oversaturation, stylized filters, or AI artifacts.` |  | Neikvæð kvaðning notuð við staðfestingu, sem notar forskoðunarferli í einu stigi. Þar sem ferlið líkir eftir eimuðum framleiðsluályktunum í tveimur stigum er leiðsögn þess og forskoðunargæði frábrugðin lokaútkomunni. |
| `validation_number_of_frames` |  | integer | no | `89` | 9 – 121 | Fjöldi ramma í hverju staðfestingarmyndbandi. |
| `validation_frame_rate` |  | integer | no | `24` | 8 – 60 | Markrammatíðni staðfestingarmyndbanda, í römmum á sekúndu; LTX-2.3 keyrir innbyggt við 24. |
| `validation_resolution` |  | enum (string) | no | `high` | `low`, `medium`, `high` | Upplausn notuð við staðfestingu. |
| `validation_aspect_ratio` |  | enum (string) | no | `1:1` | `16:9`, `1:1`, `9:16` | Stærðarhlutfall notað við staðfestingu. |
| `stg_scale` |  | number | no | `1` | 0 – 3 | Spatio-Temporal Guidance (STG)-kvarði, þar sem mælt er með 1.0 en 0.0 slekkur á STG. |
| `include_middle_keyframe` |  | boolean | no | `false` |  | Innifaling miðlykilramma við efnisgerð myndbands: true krefst `middle_image_url` í hverju staðfestingarsýni og heldur miðrammanum ásamt fyrsta og síðasta ramma í stað þess að nota aðeins fyrsta og síðasta. |

## Example input

Required parameters only:

```json
{
  "training_data_url": "https://example.com/your-file.zip"
}
```

A fuller example:

```json
{
  "training_data_url": "https://example.com/your-file.zip"
}
```

## 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/ltx23-trainer-v2/interpolate?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "training_data_url": "https://example.com/your-file.zip"
  }'

# 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/ltx23-trainer-v2/interpolate?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "training_data_url": "https://example.com/your-file.zip"
  }),
});
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 = {
    "training_data_url": "https://example.com/your-file.zip",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/ltx23-trainer-v2/interpolate", 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": "ltx23-trainer-v2/interpolate",
      "input": {
        "training_data_url": "https://example.com/your-file.zip"
      },
      "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": "ltx23-trainer-v2/interpolate",
  "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": 4800,
    "usd": "4.80",
    "charged": 4800,
    "refunded": 0
  },
  "input": {
    "training_data_url": "https://example.com/your-file.zip"
  },
  "output": {
    "video": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_name": "0-output.jpeg",
      "file_size": 1843200
    },
    "audio": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_name": "0-output.jpeg",
      "file_size": 1843200
    },
    "lora_file": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_name": "0-output.jpeg",
      "file_size": 1843200
    },
    "config_file": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_name": "0-output.jpeg",
      "file_size": 1843200
    },
    "debug_dataset": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_name": "0-output.jpeg",
      "file_size": 1843200
    }
  },
  "outputs": [
    {
      "type": "file",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_size": 1843200,
      "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} \| null | Sameinuð myndbandsforskoðun úr staðfestingu, þegar hún er tiltæk fyrir endapunkta sem búa til myndband. |
| `audio` | object {url, content_type, file_name, file_size} \| null | Sameinað hljóð úr staðfestingu, gefið sem forskoðun þegar það er tiltækt fyrir þessar hljóðeingöngu-leiðir: /audio-inpaint, /audio-extend-suffix, /audio-extend-prefix, /t2a, /a2a og /v2a. |
| `lora_file` | object {url, content_type, file_name, file_size} | URL á þjálfaðar LoRA-vigtir á .safetensors-sniði. |
| `config_file` | object {url, content_type, file_name, file_size} | Uppsetning fyrir uppsetningu ályktunarendapunkts. |
| `debug_dataset` | object {url, content_type, file_name, file_size} \| null | Villuleitarúttak sem er tiltækt þegar `debug_dataset` er virkt: skráasafn sem hægt er að hlaða niður og inniheldur þjálfunargögnin eftir forvinnslu. |

## Related models

- [LTX 2.3 Trainer (V2) - Audio Inpainting](https://doitong.com/developers/models/ltx23-trainer-v2/audio-inpaint.md) (`ltx23-trainer-v2/audio-inpaint`): $0.0023 / step
- [LTX 2.3 Trainer (V2) - Audio+Video Reference IC-LoRA](https://doitong.com/developers/models/ltx23-trainer-v2/ic-lora/av2av.md) (`ltx23-trainer-v2/ic-lora/av2av`): $0.0068 / step
- [LTX 2.3 Trainer (V2) - Audio+Video Reference Transformation](https://doitong.com/developers/models/ltx23-trainer-v2/av2av.md) (`ltx23-trainer-v2/av2av`): $0.0068 / step
- [LTX 2.3 Trainer (V2) - Audio-to-Audio](https://doitong.com/developers/models/ltx23-trainer-v2/a2a.md) (`ltx23-trainer-v2/a2a`): $0.0023 / step
- [LTX 2.3 Trainer (V2) - Audio-to-Audio IC-LoRA](https://doitong.com/developers/models/ltx23-trainer-v2/ic-lora/a2a.md) (`ltx23-trainer-v2/ic-lora/a2a`): $0.0023 / step
- [LTX 2.3 Trainer (V2) - Audio-to-Video](https://doitong.com/developers/models/ltx23-trainer-v2/a2v.md) (`ltx23-trainer-v2/a2v`): $0.006 / step
- [LTX 2.3 Trainer (V2) - Backward Audio Extension](https://doitong.com/developers/models/ltx23-trainer-v2/audio-extend-suffix.md) (`ltx23-trainer-v2/audio-extend-suffix`): $0.0023 / step
- [LTX 2.3 Trainer (V2) - Backward Video Extension](https://doitong.com/developers/models/ltx23-trainer-v2/extend-suffix.md) (`ltx23-trainer-v2/extend-suffix`): $0.0061 / step

## Links

- HTML page: https://doitong.com/developers/models/ltx23-trainer-v2/interpolate
- 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=ltx23-trainer-v2/interpolate
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/ltx23-trainer-v2/interpolate