> ## Documentation Index
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> Use this file to discover all available pages before exploring further.

# KlingStartEndFrameNode - ComfyUI Built-in Node Documentation

> Complete documentation for the KlingStartEndFrameNode 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/KlingStartEndFrameNode/en.md)

Kling Start-End Frame to Video node creates a video sequence that transitions between your provided start and end images. It generates all the frames in between to produce a smooth transformation from the first frame to the last frame. This node calls the image-to-video API but only supports the input options that work with the `image_tail` request field.

## Inputs

| Parameter         | Data Type | Required | Range                                                                       | Description                                                                                                                                                                                |
| ----------------- | --------- | -------- | --------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `start_frame`     | IMAGE     | Yes      | -                                                                           | Reference Image - URL or Base64 encoded string, cannot exceed 10MB, resolution not less than 300\*300px, aspect ratio between 1:2.5 \~ 2.5:1. Base64 should not include data:image prefix. |
| `end_frame`       | IMAGE     | Yes      | -                                                                           | Reference Image - End frame control. URL or Base64 encoded string, cannot exceed 10MB, resolution not less than 300\*300px. Base64 should not include data:image prefix.                   |
| `prompt`          | STRING    | Yes      | -                                                                           | Positive text prompt                                                                                                                                                                       |
| `negative_prompt` | STRING    | Yes      | -                                                                           | Negative text prompt                                                                                                                                                                       |
| `cfg_scale`       | FLOAT     | No       | 0.0-1.0                                                                     | Controls the strength of the prompt guidance (default: 0.5)                                                                                                                                |
| `aspect_ratio`    | COMBO     | No       | "16:9"<br />"9:16"<br />"1:1"<br />"21:9"<br />"9:21"<br />"3:4"<br />"4:3" | The aspect ratio for the generated video (default: "16:9")                                                                                                                                 |
| `mode`            | COMBO     | No       | Multiple options available                                                  | The configuration to use for the video generation following the format: mode / duration / model\_name. (default: third option from available modes)                                        |

**Image Constraints:**

* Both `start_frame` and `end_frame` must be provided and cannot exceed 10MB file size
* Minimum resolution: 300×300 pixels for both images
* `start_frame` aspect ratio must be between 1:2.5 and 2.5:1
* Base64 encoded images should not include the "data:image" prefix

## Outputs

| Output Name | Data Type | Description                               |
| ----------- | --------- | ----------------------------------------- |
| `output`    | VIDEO     | The generated video sequence              |
| `video_id`  | STRING    | Unique identifier for the generated video |
| `duration`  | STRING    | Duration of the generated video           |