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---
title: generateImageMetadata
description: Learn how to generate multiple images in a single Metadata API special file.
related:
title: Next Steps
description: View all the Metadata API options.
links:
- app/api-reference/file-conventions/metadata
---
You can use `generateImageMetadata` to generate different versions of one image or return multiple images for one route segment. This is useful for when you want to avoid hard-coding metadata values, such as for icons.
## Parameters
`generateImageMetadata` function accepts the following parameters:
#### `params` (optional)
An object containing the [dynamic route parameters](/docs/app/api-reference/file-conventions/dynamic-routes) object from the root segment down to the segment `generateImageMetadata` is called from.
```tsx filename="icon.tsx" switcher
export function generateImageMetadata({
params,
}: {
params: { slug: string }
}) {
// ...
}
```
```jsx filename="icon.js" switcher
export function generateImageMetadata({ params }) {
// ...
}
```
| Route | URL | `params` |
| ------------------------------- | ----------- | ------------------------- |
| `app/shop/icon.js` | `/shop` | `undefined` |
| `app/shop/[slug]/icon.js` | `/shop/1` | `{ slug: '1' }` |
| `app/shop/[tag]/[item]/icon.js` | `/shop/1/2` | `{ tag: '1', item: '2' }` |
## Returns
The `generateImageMetadata` function should return an `array` of objects containing the image's metadata such as `alt` and `size`. In addition, each item **must** include an `id` value which will be passed to the props of the image generating function.
| Image Metadata Object | Type |
| --------------------- | ----------------------------------- |
| `id` | `string` (required) |
| `alt` | `string` |
| `size` | `{ width: number; height: number }` |
| `contentType` | `string` |
```tsx filename="icon.tsx" switcher
import { ImageResponse } from 'next/og'
export function generateImageMetadata() {
return [
{
contentType: 'image/png',
size: { width: 48, height: 48 },
id: 'small',
},
{
contentType: 'image/png',
size: { width: 72, height: 72 },
id: 'medium',
},
]
}
export default function Icon({ id }: { id: string }) {
return new ImageResponse(
(
<div
style={{
width: '100%',
height: '100%',
display: 'flex',
alignItems: 'center',
justifyContent: 'center',
fontSize: 88,
background: '#000',
color: '#fafafa',
}}
>
Icon {id}
</div>
)
)
}
```
```jsx filename="icon.js" switcher
import { ImageResponse } from 'next/og'
export function generateImageMetadata() {
return [
{
contentType: 'image/png',
size: { width: 48, height: 48 },
id: 'small',
},
{
contentType: 'image/png',
size: { width: 72, height: 72 },
id: 'medium',
},
]
}
export default function Icon({ id }) {
return new ImageResponse(
(
<div
style={{
width: '100%',
height: '100%',
display: 'flex',
alignItems: 'center',
justifyContent: 'center',
fontSize: 88,
background: '#000',
color: '#fafafa',
}}
>
Icon {id}
</div>
)
)
}
```
### Examples
#### Using external data
This example uses the `params` object and external data to generate multiple [Open Graph images](/docs/app/api-reference/file-conventions/metadata/opengraph-image) for a route segment.
```tsx filename="app/products/[id]/opengraph-image.tsx" switcher
import { ImageResponse } from 'next/og'
import { getCaptionForImage, getOGImages } from '@/app/utils/images'
export async function generateImageMetadata({
params,
}: {
params: { id: string }
}) {
const images = await getOGImages(params.id)
return images.map((image, idx) => ({
id: idx,
size: { width: 1200, height: 600 },
alt: image.text,
contentType: 'image/png',
}))
}
export default async function Image({
params,
id,
}: {
params: { id: string }
id: number
}) {
const productId = (await params).id
const imageId = id
const text = await getCaptionForImage(productId, imageId)
return new ImageResponse(
(
<div
style={
{
// ...
}
}
>
{text}
</div>
)
)
}
```
```jsx filename="app/products/[id]/opengraph-image.js" switcher
import { ImageResponse } from 'next/og'
import { getCaptionForImage, getOGImages } from '@/app/utils/images'
export async function generateImageMetadata({ params }) {
const images = await getOGImages(params.id)
return images.map((image, idx) => ({
id: idx,
size: { width: 1200, height: 600 },
alt: image.text,
contentType: 'image/png',
}))
}
export default async function Image({ params, id }) {
const productId = (await params).id
const imageId = id
const text = await getCaptionForImage(productId, imageId)
return new ImageResponse(
(
<div
style={
{
// ...
}
}
>
{text}
</div>
)
)
}
```
## Version History
| Version | Changes |
| --------- | ----------------------------------- |
| `v13.3.0` | `generateImageMetadata` introduced. |
|