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

# RunwayImageToVideoNodeGen3a - ComfyUI Built-in Node Documentation

> Complete documentation for the RunwayImageToVideoNodeGen3a node in ComfyUI. Learn its inputs, outputs, parameters and usage.

> This documentation was AI-generated. If you find any errors or have suggestions for improvement, please feel free to contribute! [Edit on GitHub](https://github.com/Comfy-Org/embedded-docs/blob/main/comfyui_embedded_docs/docs/RunwayImageToVideoNodeGen3a/en.md)

The Runway Image to Video (Gen3a Turbo) node generates a video from a single starting frame using Runway's Gen3a Turbo model. It takes a text prompt and an initial image frame, then creates a video sequence based on the specified duration and aspect ratio. This node connects to Runway's API to process the generation remotely.

## Inputs

| Parameter     | Data Type | Required | Range                      | Description                                     |
| ------------- | --------- | -------- | -------------------------- | ----------------------------------------------- |
| `prompt`      | STRING    | Yes      | N/A                        | Text prompt for the generation (default: "")    |
| `start_frame` | IMAGE     | Yes      | N/A                        | Start frame to be used for the video            |
| `duration`    | COMBO     | Yes      | Multiple options available | Video duration selection from available options |
| `ratio`       | COMBO     | Yes      | Multiple options available | Aspect ratio selection from available options   |
| `seed`        | INT       | No       | 0-4294967295               | Random seed for generation (default: 0)         |

**Parameter Constraints:**

* The `start_frame` must have dimensions not exceeding 7999x7999 pixels
* The `start_frame` must have an aspect ratio between 0.5 and 2.0
* The `prompt` must contain at least one character (cannot be empty)

## Outputs

| Output Name | Data Type | Description                  |
| ----------- | --------- | ---------------------------- |
| `output`    | VIDEO     | The generated video sequence |