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

# generateLayerPreviewImage

> Generate a thumbnail image for a layer.

<Note>
  This API belongs to `PluginNoteAPI` and can only be called in NOTE.
</Note>

```ts wrap theme={null}
static generateLayerPreviewImage(
  notePath: string,
  page: number,
  layer: number,
  imagePath: string
): Promise<APIResponse<boolean>>;
```

**Parameters**

| Parameter   | Type     | Description                                                                                                      |
| ----------- | -------- | ---------------------------------------------------------------------------------------------------------------- |
| `notePath`  | `string` | NOTE file path                                                                                                   |
| `page`      | `number` | Page index (starts from `0`)                                                                                     |
| `layer`     | `number` | Layer index. `-1` indicates the background layer, `0` indicates the main layer, and `1~3` indicate custom layers |
| `imagePath` | `string` | Output path for the thumbnail image                                                                              |

**Returns**

* [`APIResponse<boolean>`](/en/api-reference/supernote-plugin/types/api-response):
  `result === true` indicates the layer thumbnail image was generated successfully

## Example

```ts wrap theme={null}
import { PluginNoteAPI } from 'sn-plugin-lib';

/**
 * Example: generate a thumbnail image for a layer.
 */
export async function exampleGenerateLayerPreviewImage() {
  const res = await PluginNoteAPI.generateLayerPreviewImage(
    '/storage/emulated/0/Note/demo.note',
    0,
    0,
    '/storage/emulated/0/Note/out/layer-preview.png'
  );
  if (!res.success) {
    throw new Error(res.error?.message ?? 'generateLayerPreviewImage call failed');
  }
  return res.result;
}
```