# FLUX 3 Max Keyframes to Video API

> Tạo video từ lời nhắc và tối đa 10 hình ảnh khung hình chính được ghim vào vị trí khung hình, với âm thanh tùy chọn

Tạo video chuyển động giữa các khung hình chính được ghim theo thời gian. `keyframes` nhận 1 đến 10 hình ảnh với các giá trị `frame_index` duy nhất, còn `prompt` mô tả chuyển động. `duration` từ 5 đến 20 giây, `resolution` là 720p hoặc 1080p, và `aspect_ratio` gồm các tỷ lệ từ 21:9 đến 9:16 hoặc auto. Ngoài ra có `reasoning_level` (low hoặc high) và `generate_audio`.

- Model id: `blackforestlabs/flux-3-max/keyframes-to-video`
- Made by: Black Forest Labs
- Category: Image to Video
- Output: video
- Price: from $0.0425 / second (5 s ≈ $0.213) (cheapest run $0.213 (213 API credits))
- Run: `POST https://api.doitong.ru/v1/run/blackforestlabs/flux-3-max/keyframes-to-video`
- Quote: `POST https://api.doitong.ru/v1/quote/blackforestlabs/flux-3-max/keyframes-to-video`
- Docs page: https://doitong.com/vi/developers/models/blackforestlabs/flux-3-max/keyframes-to-video

## Pricing

Price: **from $0.0425 / second (5 s ≈ $0.213)** (the lowest tier; the quote prices your exact input). Billed per second of output (`duration`, default 20).

Price rules (the first rule that matches the input wins; a parameter you leave out counts as its default):

- When `resolution` = 1080p: $0.0725 (72.5 API credits) / second

The full example input below costs $0.425 = 425 API credits (5 s × 85 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/blackforestlabs/flux-3-max/keyframes-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

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `prompt` |  | string | yes |  | ≥ 1 characters | Văn bản mô tả chuyển động của video giữa các khung hình chính. |
| `keyframes` |  | array of object {image_url, frame_index} | yes |  | 1 – 10 items | Hình ảnh khung hình chính được đặt vào video đầu ra theo `frame_index`; cung cấp tối đa 10 hình ảnh và không lặp lại chỉ mục. |
| `keyframes[].image_url` |  | string (image URL) | yes |  |  | URL hình ảnh khung hình chính; chấp nhận PNG, JPEG hoặc WebP. |
| `keyframes[].frame_index` |  | integer | yes |  | ≥ 0 | Vị trí khung hình chính sử dụng một chỉ mục khung hình riêng cho mỗi khung hình chính, có giới hạn trên là `duration * 24`; đầu ra chạy ở 24 fps. |
| `duration` |  | enum (integer) | no | `5` | `5`, `6`, `7`, `8`, `9`, `10`, `11`, `12`, `13`, `14`, `15`, `16`, `17`, `18`, `19`, `20` | Thời lượng video đầu ra, tính bằng giây. |
| `resolution` |  | enum (string) | no | `720p` | `720p`, `1080p` | Độ phân giải của video đầu ra. |
| `reasoning_level` |  | enum (string) | no | `high` | `low`, `high` | Mức độ suy luận kiểm soát sự cân bằng giữa tốc độ tạo sinh và công sức mà harness dành để hiểu lời nhắc: mức cao hơn sẽ mất nhiều thời gian hơn. |
| `aspect_ratio` |  | enum (string) | no | `auto` | `auto`, `21:9`, `2:1`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | Tỷ lệ khung hình của video được tạo; `auto` khớp với hình ảnh đầu tiên, trừ khi đầu vào là lời nhắc văn bản, khi đó chọn 16:9. |
| `generate_audio` |  | boolean | no | `true` |  | Kiểm soát việc video có bao gồm âm thanh được tạo hay không. |
| `seed` |  | integer \| null | no |  |  | Seed tạo sinh; sử dụng giá trị ngẫu nhiên nếu bỏ qua. |

## Example input

Required parameters only:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "keyframes": [
    {
      "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
      "frame_index": 0
    }
  ]
}
```

A fuller example:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "keyframes": [
    {
      "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
      "frame_index": 0
    }
  ]
}
```

## 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/blackforestlabs/flux-3-max/keyframes-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",
    "keyframes": [
      {
        "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
        "frame_index": 0
      }
    ]
  }'

# 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/blackforestlabs/flux-3-max/keyframes-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",
    "keyframes": [
      {
        "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
        "frame_index": 0
      }
    ]
  }),
});
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",
    "keyframes": [
        {
            "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
            "frame_index": 0,
        },
    ],
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/blackforestlabs/flux-3-max/keyframes-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": "blackforestlabs/flux-3-max/keyframes-to-video",
      "input": {
        "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
        "keyframes": [
          {
            "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
            "frame_index": 0
          }
        ]
      },
      "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": "blackforestlabs/flux-3-max/keyframes-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": 425,
    "usd": "0.425",
    "charged": 425,
    "refunded": 0
  },
  "input": {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "keyframes": [
      {
        "image_url": "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
        "frame_index": 0
      }
    ]
  },
  "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,
    "timings": {}
  },
  "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, width, height, fps, duration, num_frames} | Video do mô hình tạo ra. |
| `seed` | integer | Giá trị seed được dùng trong quá trình tạo sinh. |
| `timings` | object | Dữ liệu thời gian, trong đó phần mở rộng lời nhắc, giải mã và tải lên bị loại khỏi `inference`, chỉ đo thời gian khử nhiễu video của mô hình, tính bằng giây. |

## Related models

- [FLUX 3 Max Text to Video](https://doitong.com/developers/models/blackforestlabs/flux-3-max/text-to-video.md) (`blackforestlabs/flux-3-max/text-to-video`): from $0.0425 / second of output video
- [FLUX 3 Max Image to Video](https://doitong.com/developers/models/blackforestlabs/flux-3-max/image-to-video.md) (`blackforestlabs/flux-3-max/image-to-video`): from $0.0425 / second of output video
- [Grok Imagine Video 1.5 Image to Video](https://doitong.com/developers/models/xai/grok-imagine-video/v1.5/image-to-video.md) (`xai/grok-imagine-video/v1.5/image-to-video`): from $0.082 / second
- [Kling 3.0 Pro Image to Video](https://doitong.com/developers/models/kling-video/v3/pro/image-to-video.md) (`kling-video/v3/pro/image-to-video`): from $0.112 / second
- [LTX 2.5 Pro Image to Video](https://doitong.com/developers/models/lightricks/ltx-2.5/image-to-video/pro.md) (`lightricks/ltx-2.5/image-to-video/pro`): from $0.12 / second
- [MiniMax H3 Image to Video](https://doitong.com/developers/models/minimax/h3/image-to-video.md) (`minimax/h3/image-to-video`): from $0.05 / second
- [Seedance 2.0 Fast Image to Video](https://doitong.com/developers/models/bytedance/seedance-2.0/fast/image-to-video.md) (`bytedance/seedance-2.0/fast/image-to-video`): from $0.113 / second
- [Seedance 2.0 Image to Video](https://doitong.com/developers/models/bytedance/seedance-2.0/image-to-video.md) (`bytedance/seedance-2.0/image-to-video`): from $0.141 / second

## Links

- HTML page: https://doitong.com/developers/models/blackforestlabs/flux-3-max/keyframes-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=blackforestlabs/flux-3-max/keyframes-to-video
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/blackforestlabs/flux-3-max/keyframes-to-video
