This quartz filter compresses the JPEG in a PDF, while maintaining usable resolution. The purpose of this quartz filter is to use it with Apple's Preview.app to quickly reduce the file size of images in PDF's while maintaining legibility. macOS does have a built-in filter called "Reduce File Size" that has the same purpose, however this filter is too aggressive and converts images to a resolution that is too low.
To install this filter for the currently logged-in user, run the below command in Terminal:
mkdir -p ~/Library/Filters/ && curl -o ~/Library/Filters/Compress\ Images\ in\ PDF.qfilter https://raw.githubusercontent.com/superman-lopez/compressjpeginpreview/master/Compress%20Images%20in%20PDF.qfilter
After this the filter can be used in Preview.app (and other apps that support quartz filters).
- Open the PDF in Preview.app
- Select File and Export...
- Choose Format to be PDF
- Choose Quartz Filter to Compress Images in PDF
- Choose your prefered destination and click Save
To uninstall simply run:
rm ~/Library/Filters/Compress\ Images\ in\ PDF.qfilter