# Kling O1 Reference Video to Video [Pro] API

> Video-til-video på Pro-niveau, der skaber en ny optagelse styret af et referenceklip, med valgfri bevaret lyd

Tager en referencevideo i `video_url` (mp4 eller mov, 3 til 10 sekunder, 720 til 2160 px, højst 200MB) og en `prompt` på højst 2500 tegn. Stilbilleder og `elements` kan tilføjes, 4 i alt, og angives som @Image1 eller @Element1. Indstil `keep_audio` for at bevare kildelyden. Billedformatet kan være auto, 16:9, 9:16 eller 1:1, med en varighed på 3 til 10 sekunder.

- Model id: `kling-video/o1/video-to-video/reference`
- Made by: Kling
- Category: Video to Video
- Output: video
- Price: $0.168 / second (5 s ≈ $0.84) (cheapest run $0.84 (840 API credits))
- Run: `POST https://api.doitong.ru/v1/run/kling-video/o1/video-to-video/reference`
- Quote: `POST https://api.doitong.ru/v1/quote/kling-video/o1/video-to-video/reference`
- Docs page: https://doitong.com/da/developers/models/kling-video/o1/video-to-video/reference

## Pricing

Price: **$0.168 / second (5 s ≈ $0.84)**. Billed per second of output (`duration`, default 10).

The full example input below costs $0.84 = 840 API credits (5 s × 168 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.ru/v1/quote/kling-video/o1/video-to-video/reference` 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 |
|---|---|---|---|---|---|---|
| `enable_safety_checker` |  | boolean | no | `true` |  | Sikkerhedstjek kan kun deaktiveres med kontogodkendelse; anmodninger uden godkendelse bliver altid kontrolleret. |
| `prompt` |  | string | yes |  | ≤ 2500 characters | Ord­nede referencer bruger @Element1, @Element2 osv. for elementer og @Image1, @Image2 osv. for billeder. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL, der peger på en referencevideo i .mp4- eller .mov-format, højst 200MB. Begge dimensioner skal være mellem 720px og 2160px, med en billedhastighed på 24.0–60.0 FPS og en varighed på 3–10 sekunder (højst 10.05 sekunder). Timeout er 30.0 sekunder. |
| `keep_audio` |  | boolean | no | `false` |  | Styrer, om videoens oprindelige lyd bevares. |
| `image_urls` | `images` | array of image URL \| null | no |  |  | Billeder, der styrer stil eller udseende, adresseret i prompten med @Image1, @Image2 osv. Ved videoinput må elementer og referencebilleder tilsammen ikke overstige 4 elementer. Hver fil er begrænset til 50 MB, med bredde og højde på mindst 300 px og et formatforhold fra 0.40 til 2.50. |
| `elements` |  | array of object {frontal_image_url, reference_image_urls} \| null | no |  |  | Figurer eller objekter, der skal medtages, adresseret i prompten med @Element1, @Element2 osv. Ved videoinput må elementer og referencebilleder tilsammen ikke overstige 4 elementer. |
| `elements[].frontal_image_url` |  | string (image URL) | yes |  |  | Frontalt billede, der viser elementets primære visning, begrænset til 50 MB. Bredde og højde skal hver være mindst 300 px, med et formatforhold fra 0.40 til 2.50. Timeout er 20 sekunder. |
| `elements[].reference_image_urls` |  | array of image URL | no |  |  | Angiv 1–3 ekstra referencebilleder, der viser forskellige vinkler. Hvert billede skal have et formatforhold mellem 0.40 og 2.50, måle mindst 300px i begge dimensioner og højst være 50.0MB. |
| `aspect_ratio` |  | enum (string) | no | `auto` | `auto`, `16:9`, `9:16`, `1:1` | Forholdet mellem bredde og højde for frames i den genererede video. Valg af 'auto' vælger automatisk det formatforhold, der ligger nærmest inputvideoens. |
| `duration` |  | enum (string) | no | `5` | `3`, `4`, `5`, `6`, `7`, `8`, `9`, `10` | Videolængde målt i sekunder. |

File parameters (`video`, `images`) 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/kling-video/o1/video-to-video/reference?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/kling-video/o1/video-to-video/reference?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/kling-video/o1/video-to-video/reference", 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": "kling-video/o1/video-to-video/reference",
      "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": "kling-video/o1/video-to-video/reference",
  "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": 840,
    "usd": "0.84",
    "charged": 840,
    "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
    }
  },
  "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} | Video produceret af modellen. |

## Related models

- [Kling O1 First Frame Last Frame to Video \[Pro\]](https://doitong.com/developers/models/kling-video/o1/image-to-video.md) (`kling-video/o1/image-to-video`): $0.112 / second
- [Kling O1 First Frame Last Frame to Video \[Standard\]](https://doitong.com/developers/models/kling-video/o1/standard/image-to-video.md) (`kling-video/o1/standard/image-to-video`): $0.084 / second
- [Kling O1 Reference Image to Video \[Pro\]](https://doitong.com/developers/models/kling-video/o1/reference-to-video.md) (`kling-video/o1/reference-to-video`): $0.112 / second
- [Kling O1 Reference Image to Video \[Standard\]](https://doitong.com/developers/models/kling-video/o1/standard/reference-to-video.md) (`kling-video/o1/standard/reference-to-video`): $0.084 / second
- [Kling O1 Edit Video \[Pro\]](https://doitong.com/developers/models/kling-video/o1/video-to-video/edit.md) (`kling-video/o1/video-to-video/edit`): $0.168 / second of input video
- [Kling O1 Edit Video \[Standard\]](https://doitong.com/developers/models/kling-video/o1/standard/video-to-video/edit.md) (`kling-video/o1/standard/video-to-video/edit`): $0.126 / second of input video
- [Kling O1 Reference Video to Video \[Standard\]](https://doitong.com/developers/models/kling-video/o1/standard/video-to-video/reference.md) (`kling-video/o1/standard/video-to-video/reference`): $0.126 / second
- [Kling O3 Edit Video \[Pro\]](https://doitong.com/developers/models/kling-video/o3/pro/video-to-video/edit.md) (`kling-video/o3/pro/video-to-video/edit`): $0.168 / second of input video

## Links

- HTML page: https://doitong.com/developers/models/kling-video/o1/video-to-video/reference
- 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=kling-video/o1/video-to-video/reference
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/kling-video/o1/video-to-video/reference
