# Scenario Compose Video — API Reference

Model ID: `model_scenario-compose-video`

---

## Authentication

Scenario API uses HTTP Basic Auth. Encode your credentials in Base64 and pass them as the `Authorization` header.

```
Authorization: Basic base64("<API_KEY>:<API_SECRET>")
```

- **API_KEY** and **API_SECRET** are found in your [Scenario Project Settings](https://app.scenario.com/team&tab=project_api_keys) under API Keys.
- In shell: `$(echo -n '<API_KEY>:<API_SECRET>' | base64)`
- In JavaScript: `btoa("<API_KEY>:<API_SECRET>")`
- In Python: `base64.b64encode(f"{api_key}:{api_secret}".encode()).decode()`

---

## Generate

**Endpoint:** `POST https://api.cloud.scenario.com/v1/generate/custom/model_scenario-compose-video`

### Parameters

| Parameter | Type | Required | Default | Description |
|-----------|------|----------|---------|-------------|
| `layers` | object[] | yes | - | Array of layers to compose (images, videos, audio). At least one video layer is required. |
| `canvasMode` | string | - | `auto` | Canvas size mode. 'auto' computes from layers, 'custom' uses specified dimensions. |
| `canvasWidth` | number | - | - | Output canvas width in pixels (required when canvas_mode='custom') |
| `canvasHeight` | number | - | - | Output canvas height in pixels (required when canvas_mode='custom') |
| `backgroundColor` | string | - | `#000000` | Canvas background color (hex format #RRGGBB) or 'transparent' |
| `durationMode` | string | - | `auto` | Duration mode. 'auto' calculates from layers, 'custom' uses specified duration. |
| `duration` | number | - | - | Total duration in seconds (required when duration_mode='custom') |
| `fps` | number | - | `30` | Output frame rate (fps) |
| `videoOutputFormat` | string | - | `mp4` | Output video format |
| `compressionLevel` | number | - | `23` | Compression quality (CRF value, lower = higher quality, 15-51) |

### Example Requests

**cURL**

```bash
curl -X POST "https://api.cloud.scenario.com/v1/generate/custom/model_scenario-compose-video" \
  -H "Authorization: Basic $(echo -n '<API_KEY>:<API_SECRET>' | base64)" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'EOF'
{
  "layers": null,
  "canvasMode": "auto",
  "backgroundColor": "#000000",
  "durationMode": "auto",
  "fps": 30,
  "videoOutputFormat": "mp4",
  "compressionLevel": 23
}
EOF
```

**Python**

```python
import requests
import base64

api_key = "<API_KEY>"
api_secret = "<API_SECRET>"
token = base64.b64encode(f"{api_key}:{api_secret}".encode()).decode()

url = "https://api.cloud.scenario.com/v1/generate/custom/model_scenario-compose-video"
headers = {
    "Authorization": f"Basic {token}",
    "Content-Type": "application/json"
}
payload = {
    "layers": None,
    "canvasMode": "auto",
    "backgroundColor": "#000000",
    "durationMode": "auto",
    "fps": 30,
    "videoOutputFormat": "mp4",
    "compressionLevel": 23
}

response = requests.post(url, headers=headers, json=payload)
print(response.json())
```

**JavaScript**

```javascript
const token = btoa("<API_KEY>:<API_SECRET>");

const body = {
  "layers": null,
  "canvasMode": "auto",
  "backgroundColor": "#000000",
  "durationMode": "auto",
  "fps": 30,
  "videoOutputFormat": "mp4",
  "compressionLevel": 23
};

const response = await fetch(
  "https://api.cloud.scenario.com/v1/generate/custom/model_scenario-compose-video",
  {
    method: "POST",
    headers: {
      "Authorization": `Basic ${token}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify(body),
  }
);

const data = await response.json();
console.log(data);
```

---

## Retrieve Results

After submitting a generation request, you receive a `jobId`. Poll the job status endpoint until the job completes.

**Endpoint:** `GET https://api.cloud.scenario.com/v1/jobs/{jobId}`

**Headers:**
```
Authorization: Basic base64("<API_KEY>:<API_SECRET>")
```

Poll until `job.status` is `"success"`. The generated asset IDs are in `job.metadata.assetIds`.

**Example response:**
```json
{
  "job": {
    "jobId": "job_abc123",
    "status": "success",
    "metadata": {
      "assetIds": [
        "asset_abc123"
      ]
    }
  }
}
```

> **Important:** Generated asset URLs are **temporary** and expire after a short period. Download and store any images you wish to keep before the URL expires. More info: [Content Delivery Network (CDN)](https://docs.scenario.com/docs/content-delivery-network-cdn).

---

*Generated by [Scenario](https://app.scenario.com)*