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

# HappyHorse 1.1

> Create a 3–15 second HappyHorse video from a prompt, a first frame or image references.

Use `happyhorse-1.1` with a prompt of up to 2,500 characters. Set `seconds` to an
integer from 3 to 15 and choose `720P` or `1080P`. Supported `aspect_ratio` values
are `16:9`, `9:16`, `1:1`, `4:3` and `3:4`.

For image-to-video, provide `first_frame_image`. For reference generation, provide
one to nine `image_urls`. These two input forms are mutually exclusive. References
must be publicly reachable image URLs. This contract does not accept source video,
audio references or a caller-selected upstream model.

```json theme={null}
{
  "model": "happyhorse-1.1",
  "prompt": "An illustrated forest, morning light, a slow camera move past the trees.",
  "seconds": 3,
  "resolution": "720P",
  "aspect_ratio": "16:9"
}
```

Send the request to `https://api.snapgen.org/v1/videos` with your Bearer key and a
unique `Idempotency-Key`. Query [`GET /v1/tasks/{id}`](https://docs.snapgen.org/api-reference/task-status)
for the result. An image reference is optional; the first-frame form is:

```json theme={null}
{
  "model": "happyhorse-1.1",
  "prompt": "Keep the scene consistent and move gently through the forest.",
  "first_frame_image": "https://your-cdn.example/forest.png",
  "seconds": 5,
  "resolution": "1080P",
  "aspect_ratio": "16:9"
}
```

Current launch prices are $0.26 per output second at 720P and $0.33 at 1080P.
The requested duration and resolution determine the reservation. Availability and
current pricing come from the [Catalog](https://docs.snapgen.org/api-reference/list-models.md); a missing
channel is not silently replaced with another video model.


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