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tsconfig.json

@astrojs/image 📷

⚠️ This integration is still experimental! Only node environments are supported currently, stay tuned for Deno support in the future!

This Astro integration makes it easy to optimize images in your Astro project, with full support for SSG builds and server-side rendering!

Why @astrojs/image?

Images play a big role in overall site performance and usability. Serving properly sized images makes all the difference but is often tricky to automate.

This integration provides <Image /> and <Picture> components as well as a basic image transformer powered by sharp, with full support for static sites and server-side rendering. The built-in sharp transformer is also replacable, opening the door for future integrations that work with your favorite hosted image service.

Installation

Quick Install

The astro add command-line tool automates the installation for you. Run one of the following commands in a new terminal window. (If you aren't sure which package manager you're using, run the first command.) Then, follow the prompts, and type "y" in the terminal (meaning "yes") for each one.

# Using NPM
npx astro add image
# Using Yarn
yarn astro add image
# Using PNPM
pnpx astro add image

Then, restart the dev server by typing CTRL-C and then npm run astro dev in the terminal window that was running Astro.

Because this command is new, it might not properly set things up. If that happens, feel free to log an issue on our GitHub and try the manual installation steps below.

Manual Install

First, install the @astrojs/image package using your package manager. If you're using npm or aren't sure, run this in the terminal:

npm install @astrojs/image

Then, apply this integration to your astro.config.* file using the integrations property:

astro.config.mjs

import image from '@astrojs/image';

export default {
  // ...
  integrations: [image()],
}

Then, restart the dev server.

Usage

The built-in <Image /> component is used to create an optimized <img /> for both remote images hosted on other domains as well as local images imported from your project's src directory.

The included sharp transformer supports resizing images and encoding them to different image formats. Third-party image services will be able to add support for custom transformations as well (ex: blur, filter, rotate, etc).

Configuration

The intergration can be configured to run with a different image service, either a hosted image service or a full image transformer that runs locally in your build or SSR deployment.

During development, local images may not have been published yet and would not be available to hosted image services. Local images will always use the built-in sharp service when using astro dev.

There are currently no other configuration options for the @astrojs/image integration. Please open an issue if you have a compelling use case to share.

config.serviceEntryPoint

The serviceEntryPoint should resolve to the image service installed from NPM. The default entry point is @astrojs/image/sharp, which resolves to the entry point exported from this integration's package.json.

// astro.config.mjs
import image from '@astrojs/image';

export default {
  integrations: [image({
    // Example: The entrypoint for a third-party image service installed from NPM
    serviceEntryPoint: 'my-image-service/astro.js'
  })],
}

Examples

Local images

Image files in your project's src directory can be imported in frontmatter and passed directly to the <Image /> component. All other properties are optional and will default to the original image file's properties if not provided.

---
import { Image } from '@astrojs/image/components';
import heroImage from '../assets/hero.png';
---

// optimized image, keeping the original width, height, and image format
<Image src={heroImage} />

// height will be recalculated to match the original aspect ratio
<Image src={heroImage} width={300} />

// cropping to a specific width and height
<Image src={heroImage} width={300} height={600} />

// cropping to a specific aspect ratio and converting to an avif format
<Image src={heroImage} aspectRatio="16:9" format="avif" />

// image imports can also be inlined directly
<Image src={import('../assets/hero.png')} />
Remote images

Remote images can be transformed with the <Image /> component. The <Image /> component needs to know the final dimensions for the <img /> element to avoid content layout shifts. For remote images, this means you must either provide width and height, or one of the dimensions plus the required aspectRatio.

---
import { Image } from '@astrojs/image/components';

const imageUrl = 'https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png';
---

// cropping to a specific width and height
<Image src={imageUrl} width={544} height={184} />

// height will be recalculated to match the aspect ratio
<Image src={imageUrl} width={300} aspectRatio={16/9} />

// cropping to a specific height and aspect ratio and converting to an avif format
<Image src={imageUrl} height={200} aspectRatio="16:9" format="avif" />
Images in markdown

The <Image /> component can also be used to optimize images in markdown pages. For local images imported from your project's src directory, use Astro's the setup frontmatter to import the image file.

---
setup: |
  import { Image } from '@astrojs/image/components'
  import hero from '../../assets/blog/introducing-astro.jpg'
title: Hello world!
publishDate: 12 Sep 2021
name: Nate Moore
value: 128
description: Just a Hello World Post!
---

<Image src={hero} width={640} />
<Image src="https://example.com/image.jpg" width={640} aspectRatio="16:9" />
Responsive pictures

The <Picture /> component can be used to automatically build a <picture> with multiple sizes and formats. Check out MDN for a deep dive into responsive images and art direction.

By default, the picture will include formats for avif and webp in addition to the image's original format.

For remote images, an aspectRatio is required to ensure the correct height can be calculated at build time.

---
import { Picture } from '@astrojs/image/components';
import hero from '../assets/hero.png';

const imageUrl = 'https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png';
---

// Local image with multiple sizes
<Picture src={hero} widths={[200, 400, 800]} sizes="(max-width: 800px) 100vw, 800px" alt="My hero image" />

// Remote image (aspect ratio is required)
<Picture src={imageUrl} widths={[200, 400, 800]} aspectRatio="4:3" sizes="(max-width: 800px) 100vw, 800px" alt="My hero image" />

// Inlined imports are supported
<Picture src={import("../assets/hero.png")} widths={[200, 400, 800]} sizes="(max-width: 800px) 100vw, 800px" alt="My hero image" />

Troubleshooting

  • If your installation doesn't seem to be working, make sure to restart the dev server.
  • If you edit and save a file and don't see your site update accordingly, try refreshing the page.
  • If you edit and save a file and don't see your site update accordingly, try refreshing the page.
  • If refreshing the page doesn't update your preview, or if a new installation doesn't seem to be working, then restart the dev server.

For help, check out the #support-threads channel on Discord. Our friendly Support Squad members are here to help!

You can also check our Astro Integration Documentation for more on integrations.

Contributing

This package is maintained by Astro's Core team. You're welcome to submit an issue or PR!

Changelog

See CHANGELOG.md for a history of changes to this integration.