# Kling O1 Reference Video to Video [Pro] API

> Pro-tier na video-to-video na gumagawa ng bagong shot batay sa reference clip, na may optional na pagpapanatili ng audio

Tumatanggap ng reference na video sa `video_url` (mp4 o mov, 3 hanggang 10 segundo, 720 hanggang 2160 px, hanggang 200MB) at `prompt` na hanggang 2500 character. Maaaring magdagdag ng mga larawan ng estilo at `elements`, hanggang 4 lahat, na tinutukoy bilang @Image1 o @Element1. Itakda ang `keep_audio` para panatilihin ang source sound. Maaaring auto, 16:9, 9:16 o 1:1 ang aspect ratio, na may tagal na 3 hanggang 10 segundo.

- 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/fil/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` |  | Maaaring i-disable ang safety checks lamang kapag awtorisado ang account; ang mga kahilingang walang awtorisasyon ay palaging sasailalim sa checking. |
| `prompt` |  | string | yes |  | ≤ 2500 characters | Gamitin ang @Element1, @Element2, at iba pa para sa mga elementong nakaayos, at ang @Image1, @Image2, at iba pa para sa mga larawan. |
| `video_url` | `video` | string (video URL) | yes |  |  | URL na tumutukoy sa reference video sa .mp4 o .mov format, na hindi lalampas sa 200MB. Dapat nasa pagitan ng 720px at 2160px ang parehong dimension, may frame rate na 24.0–60.0 FPS, at tagal na 3–10 segundo (10.05 segundo maximum). Ang timeout ay 30.0 segundo. |
| `keep_audio` |  | boolean | no | `false` |  | Kinokontrol kung pananatilihin ang orihinal na audio ng video. |
| `image_urls` | `images` | array of image URL \| null | no |  |  | Mga larawang gumagabay sa style o appearance, na tinutukoy sa prompt gamit ang @Image1, @Image2, at iba pa. Kapag may video input, hindi maaaring lumampas sa 4 entries ang pinagsamang elements at reference larawan. Limitado sa 50 MB ang bawat file, na may hindi bababa sa 300 px na lapad at taas at aspect ratio na 0.40 hanggang 2.50. |
| `elements` |  | array of object {frontal_image_url, reference_image_urls} \| null | no |  |  | Mga character o object na isasama, na tinutukoy sa prompt gamit ang @Element1, @Element2, at iba pa. Kapag may video input, hindi maaaring lumampas sa 4 entries ang pinagsamang elements at reference larawan. |
| `elements[].frontal_image_url` |  | string (image URL) | yes |  |  | Frontal na larawang nagbibigay ng pangunahing view ng element, na limitado sa 50 MB. Dapat hindi bababa sa 300 px ang lapad at taas, at nasa pagitan ng 0.40 at 2.50 ang aspect ratio. Ang timeout ay 20 segundo. |
| `elements[].reference_image_urls` |  | array of image URL | no |  |  | Magbigay ng 1–3 karagdagang reference na larawan na nagpapakita ng iba't ibang anggulo. Dapat nasa pagitan ng 0.40 at 2.50 ang aspect ratio ng bawat larawan, hindi bababa sa 300px ang parehong dimension, at hindi lalampas sa 50.0MB. |
| `aspect_ratio` |  | enum (string) | no | `auto` | `auto`, `16:9`, `9:16`, `1:1` | Ratio ng lapad sa taas ng mga frame sa nabuong video. Kapag pinili ang 'auto', awtomatikong pinipili ang pinakamalapit na ratio sa input video. |
| `duration` |  | enum (string) | no | `5` | `3`, `4`, `5`, `6`, `7`, `8`, `9`, `10` | Haba ng video na sinusukat sa segundo. |

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} | Videong ginawa ng modelo. |

## 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