Use Preview: Open the PDF in Preview, click File > Export, select “Reduce File Size” under Quartz Filter, and save. Use ColorSync Utility: Open the PDF in ColorSync Utility, click File > Export, ...
You can make your own filters for reducing or otherwise adjusting images when exporting in OS X's Preview application. Topher, an avid Mac user for the past 15 years, has been a contributing author to ...