While other image optimization tools are available from the command line, ImageOptim-CLI exists because the current benchmarks suggest that ImageOptim, ImageAlpha and JPEGmini currently outperform those alternatives over lossless and lossy optimizations.
ImageOptim-CLI is written in TypeScript and AppleScript but is distributed as a self-contained executable binary, you don't need Node.js installed to use ImageOptim-CLI.
Check out this short video demo of ImageOptim-CLI to see how it works.
npm is the recommended way to install ImageOptim-CLI as it is the most convenient.
npm install -g imageoptim-cli
Otherwise, you can install manually by downloading the latest zip then adding ImageOptim-CLI to your $PATH.
curl --output imageoptim-cli.zip https://registry.npmjs.org/imageoptim-cli/-/imageoptim-cli-2.0.0.tgz unzip imageoptim-cli.zip export PATH=$PATH:imageoptim-cli/bin
Saving somewhere in your home directory such as
~/imageoptim-cliis recommended, but not essential. Saving to
/Applicationsis not recommended, do not do this.
📝 Usage and Examples
$ imageoptim --help Usage: imageoptim [options] [patterns...] Options: -V, --version output the version number -a, --imagealpha enable ImageAlpha -j, --jpegmini enable JPEGmini -C, --no-color output to the terminal without colors -I, --no-imageoptim disable ImageOptim -Q, --no-quit do not quit apps once finished -S, --no-stats do not display file size savings and quality loss information --number-of-colors <n> ImageAlpha palette size, defaults to 256 --quality <min>-<max> ImageAlpha quality range from 0-100, defaults to 65-80 --speed <n> ImageAlpha speed from 1 (brute-force) to 10 (fastest), defaults to 1 -h, --help output usage information Supported Apps: ImageAlpha: https://pngmini.com ImageOptim: https://imageoptim.com JPEGmini Lite: https://itunes.apple.com/us/app/jpegmini-lite/id525742250 JPEGmini Pro: https://itunes.apple.com/us/app/jpegmini-pro/id887163276 JPEGmini: https://itunes.apple.com/us/app/jpegmini/id498944723 Examples: Run ImageOptim.app over every image in current directory imageoptim Run ImageAlpha.app and ImageOptim.app over every PNG in current directory imageoptim --imagealpha '**/*.png' Run ImageAlpha.app and JPEGmini.app over every JPG in current directory imageoptim --jpegmini '**/*.jpg' '**/*.jpeg' Run ImageOptim.app over every image in a specific directory imageoptim '~/Desktop'
⚠️ JPEGmini and support for assistive devices
You may be presented with the following message the first time you run ImageOptim-CLI with the
To automate JPEGmini we need to add Terminal.app (or iTerm.app etc) to the 'support for assistive devices' whitelist.
The JPEGmini OS X Apps don't include a command line API, so a real user is simulated by entering synthetic clicks and keyboard commands instead. This requires your permission and is easily set up in System Preferences as shown by these guides.
- Enable access for assistive devices in OS X
- OS X Mavericks: Enable access for assistive devices and applications
💡 Related Projects
Comparison of image optimization tools
ImageOptim-CLI features in this comparison of the performance of image optimisation tools alongside Kraken.io, CodeKit, grunt-contrib-imagemin, Smush.it, and TinyPNG.
Article for Smashing Magazine
The ImageOptim-CLI Workflow for Alfred app is alfred-image-optim-workflow
Do ImageOptim, ImageAlpha, or JPEGmini come bundled with the ImageOptim-CLI installation?
You will need to install these applications separately.
Do I have to pay to use ImageOptim-CLI?
The CLI, ImageOptim and ImageAlpha are all free. JPEGmini is a paid-for product but you can use ImageOptim-CLI and choose not to run JPEGmini.
The WebP image format looks promising, can you get ImageOptim-CLI to convert images to it?
WebP looks great and may well overtake the formats handled by ImageOptim-CLI, but converting images to WebP is outside ImageOptim-CLI's chosen remit.
Can you get ImageOptim-CLI to skip images it has already processed, if they haven't changed?
JPEGmini does this today, but for ImageOptim and ImageAlpha I feel a feature like this belongs in those applications rather than this automator.
ImageOptim makes the fans on my Mac run at full power.
Optimising images is a pretty intensive process, so instead of optimising one image at a time (which would take forever) — ImageOptim optimises many images at the same time until all of them are done.
A side effect of this is that the fans come on at full power to keep your machine cool while it's maxed out.
I don't think ImageAlpha is running, I can't see anything.
ImageOptim-CLI uses ImageAlpha's internal installation of pngquant so it's normal that nothing is shown on screen.
It's also possible that if you look in the Activity Monitor
you will not see
pngquant displayed but it is being run. In my experience it's only when you run
ImageOptim-CLI on a very large number of PNGs that you have enough time to spot it. ensure that
Activity Monitor's Update Frequency is set to Very Often (1 sec).
Can I use ImageOptim-CLI with JPEGmini Lite, the free version of JPEGmini?
I upgraded from JPEGmini Lite to JPEGmini but ImageOptim-CLI still says JPEGmini is not installed.
Performing the in-app upgrade leaves the app named as jpegmini-lite, so ImageOptim-CLI can't determine whether it's the free or full version. It is better to instead buy the full version of JPEGmini separately.
ImageOptim-CLI says “To automate JPEGmini we need to enable GUI Scripting”, how do I do that?
See this tutorial on how to manage Accessibility preferences and GUI Scripting. In the case of OS X Mavericks, you will want to add the Applications JPEGmini and Terminal (or equivalent such as iTerm).
Windows and Linux
Can I use ImageOptim-CLI on Windows or Linux?
ImageOptim-CLI is responsible for automating 3 OS X applications so is inherently bound to OS X for that reason.
Are there any plans for ImageOptim-CLI to support Windows or Linux?
It would first require ImageOptim, ImageAlpha, and JPEGmini to be available for those platforms.
I don't have OS X, can you recommend an alternative to ImageOptim-CLI?
❓ Get Help
There are few ways to get help:
- For bug reports and feature requests, open issues 🐛
- For direct and quick help, you can use Slack 🚀
😋 Give Help
Have an idea? Found a bug? Please see the Contributing Guide for information on how to install the project and start writing code.