sharp is what I usually use to optimize images in my Node.js scripts.

But sometimes I like using the ImageOptim macOS application to optimize images with a GUI.

This time I needed to start it from a Node.js script.

Here’s what I did.

First, import the child_process built-in Node module:

import * as child from 'node:child_process'

Then call it like this to optimize all images in a specific folder:

const images_folder = './img'

child.exec(`open -a ImageOptim ${images_folder}`)

This starts the app, you see its UI, but it’s not a big deal.

And I should note that this only works if you have the app installed.

Lessons in this unit:

0:	Introduction
1:	How to create and save an image with Node.js and Canvas
2:	How to download an image from URL in Node
3:	How to download and save an image using Node.js
4:	How to get an image width and height using Node
5:	How to turn an image into a data URI string
6:	How to download an image using Node.js
7:	How to print a canvas to a data URL
8:	Optimize images from a Node.js script
9:	▶︎ Calling the ImageOptim macOS app from a Node.js script