gatsby-remark-images

Processes images in markdown so they can be used in the production build.

In the processing, it makes images responsive by:

• Adding an elastic container to hold the size of the image while it loads to avoid layout jumps.
• Generating multiple versions of images at different widths and sets the srcset and sizes of the img element so regardless of the width of the device, the correct image is downloaded.
• Using the “blur up” technique popularized by Medium and Facebook where a small 20px wide version of the image is shown as a placeholder until the actual image is downloaded.

Install

npm install gatsby-remark-images gatsby-plugin-sharp

How to use

// In your gatsby-config.js
plugins: [
  `gatsby-plugin-sharp`,
  {
    resolve: `gatsby-transformer-remark`,
    options: {
      plugins: [
        {
          resolve: `gatsby-remark-images`,
          options: {
            // It's important to specify the maxWidth (in pixels) of
            // the content container as this plugin uses this as the
            // base for generating different widths of each image.
            maxWidth: 590,
          },
        },
      ],
    },
  },
]

Usage in Markdown

You can reference an image using the relative path, where that path is relative to the location of the Markdown file you’re typing in.

![Alt text here](./image.jpg)

By default, the text Alt text here will be used as the alt attribute of the generated img tag. If an empty alt attribute like alt="" is wished, a reserved keyword GATSBY_EMPTY_ALT can be used.

![GATSBY_EMPTY_ALT](./image.png)

Options

dynamic wrapperStyle example

{
  resolve: `gatsby-remark-images`,
  options: {
    maxWidth: 800,
    wrapperStyle: fluidResult => `flex:${_.round(fluidResult.aspectRatio, 2)};`,
  },
}

Supported Formats

This plugin will support the following formats:

• JPEG
• PNG
• WEBP
• TIFF
• AVIF

Since Sharp is used for image processing, this plugin will not support GIFs or SVGs. If you would like to render these file types with the image markdown syntax, use the gatsby-remark-copy-linked-files plugin. Do note with this it will load in the images, but won’t use the features of Sharp such as the elastic container or the blur-up enhancements.