The MaskPreview node saves mask data as a preview image to your ComfyUI output directory, allowing you to visually inspect mask data during workflow execution. It converts the input mask into a format suitable for image display and saves it with a configurable filename prefix.

## Inputs

| Parameter | Description | Data Type | Required | Range |
| --- | --- | --- | --- | --- |
| `mask` | The mask data to be previewed and saved as an image | MASK | Yes | - |
| `filename_prefix` | Prefix for the output filename (default: "ComfyUI") | STRING | No | - |
| `prompt` | Prompt information for metadata (automatically provided) | PROMPT | No | - |
| `extra_pnginfo` | Additional PNG information for metadata (automatically provided) | EXTRA_PNGINFO | No | - |

## Outputs

| Output Name | Description | Data Type |
| --- | --- | --- |
| `ui` | Contains the preview image information and metadata for display in the UI | DICT |

> 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/MaskPreview/en.md)

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