Reducing file size of pdfs – Jerome Colas’ Standard Compression quartz filter

[Apr 2019 update –  I use wecompress.com or NXPowerLite Desktop 8 for 90% compressions now: link]

[Update: if you just dropped in for the filters, here you go: link]

Apple’s Keynote has been very helpful for creating my image intensive lectures slides since it was unveiled in 2003. Each presentation I make is a very large file which is fine, but the pdf of the lecture slides are also large, which can be a problem for my students.

I do two things when creating lecture pdfs – first, I change the slide background (or theme) to white, to save on printer ink and speed when printing out slides [20180925 update – I print slides without background these days].

Then I reduce the file size of the pdf as much as possible to save students the grief of a lengthy download.

This used to be difficult, for with too much reduction, some images would get pixelated. I struggled with this until 2007 when I discovered Jerome Colas’ quartz filters. Colas provided eight filters which he developed after experimentation, but I really only use his “Standard Compression” filter.

He tweaked that for a balance of image quality and file size and it is much better than Apple’s “reduce file size” filter.

His original public folders are offline now but you can download them here.

Once downloaded, move the unzipped file to Root > Library > PDF Services. If you cannot find the folder, simply create one – which is safe to do, no worries!

When you are next viewing that large pdf, select “File > Export…”, and in the window that opens, select the standard compression filter in the Quartz Filter drop down menu.

That often reduces a 90MB file to 9MB – yes, a 90% reduction is the norm! All my slide lecture pdfs are thus below 10MB. The pdfs look fine on screen and when I peek at my student’s printed notes, they look clear.

This filter is one of the first files I copy back onto my hardisk after a clean reinstall, and is working fine on Mountain Lion. It should be every educator’s arsenal – thanks Jerome!

For other apps I use, see macapps.sivasothi.com.

Adrian Loo called me when he was preparing the SIBiol newsletter on Pages and needed to reduce the newsletter size. So I decided to post this for a reference. Hope it helps.