Google’s new Guetzli JPEG encoder does an excellent job of reducing file sizes while maintaining high quality in image integrity. Due it’s nature of compressing, though, it’s a computation process is very slow and batch processing of JPEGs isn’t available yet.
The good news is that the Image compression tinkerer Kornel Lesiński, who works on ImageOptim, says Guetzli is going to in the next version.
The better news is that until that happens, B. Scott following up on a blog post on Medium told me he coded a Mac OS Automator service that can do that now!
Downloading the files from the GitHub project repository and installing the service worker is pretty much straightforward.
Download the files from the repo. Then double-click on the
.workflow file, which should cause the Automator file should appear.
From that point on, right-click on the images you want to optimize and select
Services > GZLI_Default.
Then, if you installed Guetzli with Homebrew, the image should start the long process of optimizing, one-by-one.
The new files have
OPT appended to the filename, which should be easy to change to your personal taste in the Automator.