> ## Documentation Index
> Fetch the complete documentation index at: https://docs.unifically.com/llms.txt
> Use this file to discover all available pages before exploring further.

# SeeDance 1.5 Pro

> Professional video generation with text-to-video, image-to-video, and first/last frame support. See parameters, pricing, and API examples.

Generate videos using ByteDance SeeDance 1.5 Pro with text-to-video, image-to-video, and first/last frame workflows. Supports 4–12 second durations at 480p, 720p, or 1080p with synchronized audio generation.

## Model

```
bytedance/seedance-1.5-pro
```

## Request types

| Request type     | Required inputs                                       | Optional inputs                                                    | Notes                                                                                           |
| ---------------- | ----------------------------------------------------- | ------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------- |
| Text-to-video    | `prompt`                                              | `aspect_ratio`, `duration`, `resolution`, `generate_audio`, `seed` | No frame URLs                                                                                   |
| Image-to-video   | `first_frame_url`                                     | `prompt`, `duration`, `resolution`, `generate_audio`, `seed`       | `prompt` optional                                                                               |
| First/last frame | At least one of `first_frame_url` or `last_frame_url` | `prompt`, `duration`, `resolution`, `generate_audio`, `seed`       | `prompt` optional when a frame URL is set. Provide `first_frame_url`, `last_frame_url`, or both |

## Parameters

| Parameter         | Type    | Required    | Default  | Description                                                                                                                  |
| ----------------- | ------- | ----------- | -------- | ---------------------------------------------------------------------------------------------------------------------------- |
| `prompt`          | string  | Conditional | `""`     | Text prompt (max 5000 chars). **Required** for text-to-video. **Optional** when a frame URL is set                           |
| `aspect_ratio`    | string  | No          | `"16:9"` | `1:1`, `3:4`, `4:3`, `9:16`, `16:9`, `21:9`                                                                                  |
| `duration`        | integer | No          | `4`      | Output duration in seconds (4–12). Sent to provider as `frames = 24 × seconds + 1`                                           |
| `resolution`      | string  | No          | `"480p"` | `480p`, `720p`, `1080p`                                                                                                      |
| `generate_audio`  | boolean | No          | `true`   | Whether to generate synchronized audio for the output video                                                                  |
| `seed`            | integer | No          | —        | Seed for reproducibility. Omit for a random seed.                                                                            |
| `first_frame_url` | string  | No          | `null`   | First frame image URL. Formats: png, webp, jpeg, gif. Max 30 MB. Dimensions: 300–6000 px (short side). Aspect ratio: 0.4–2.5 |
| `last_frame_url`  | string  | No          | `null`   | Last frame image URL. Same format and size limits as `first_frame_url`                                                       |
| `nsfw_check`      | boolean | No          | `true`   | Check uploaded media inputs for NSFW content                                                                                 |

## Example - Text-to-Video

```bash theme={null}
curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "bytedance/seedance-1.5-pro",
    "input": {
      "prompt": "A dancer performing an elegant routine on a moonlit stage",
      "aspect_ratio": "9:16",
      "duration": 10,
      "resolution": "1080p"
    }
  }'
```

## Example - Image-to-Video

```bash theme={null}
curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "bytedance/seedance-1.5-pro",
    "input": {
      "prompt": "The subject slowly turns to face the camera",
      "first_frame_url": "https://example.com/portrait.jpg",
      "duration": 8,
      "resolution": "720p"
    }
  }'
```

## Example - First & Last Frame

```bash theme={null}
curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "bytedance/seedance-1.5-pro",
    "input": {
      "prompt": "The car accelerates and drives away into the sunset",
      "duration": 10,
      "resolution": "1080p",
      "first_frame_url": "https://example.com/start.jpg",
      "last_frame_url": "https://example.com/end.jpg"
    }
  }'
```

## Response

```json theme={null}
{
  "code": 200,
  "success": true,
  "data": {
    "task_id": "abc123def456",
    "status": "processing"
  }
}
```

<Note>
  **Volume discounts** are available for almost all models. Reach out at [contact@unifically.com](mailto:contact@unifically.com) to discuss custom pricing.
</Note>