Every so often I have PDF files, or have created a PDF file, and it needs slimming down a bit. For a long while I had no idea how to do this and would, for the most part, be stuck with a large PDF file that was always difficult to transfer. After a little digging into Preview I stumbled across two options which allow you to shrink the size of a PDF. Most of the time these two methods may not produce useful result, they may be as tiny as possible. However if you have used a program which isn’t designed for PDF (Word for some reason springs to mind) this trick might be useful. There are two options which you can use, both offer different results.
Both of the compression options are found in the Save As menu. First find a large PDF file that you want to shrink, any will do for this example. Go to File > Save As. In the save box there will be two drop down items. The second one is what we are interested in, Quartz Filter. From the drop down menu select none. This may be counter intuitive at first, however it allows the PDF engine to run and reduce any parts that it can. It doesn’t run any other filters. For the most part on an uncompressed PDF this will produce pleasing results. The image below show the drop down box on the Save As menu.
The option of having no Quartz Filter for the most part is sufficient. This can reduce the file size. This option is known as loss less, so it wont remove anything at all and keep things in high quality. This is needed for PDF’s with images. However for PDF’s with only text or simple geometric shapes to may be better to reduce the file size even more.
To apply a reduction in quality (however it still stays pretty good) in the drop down select “Reduce File Size”, I never notice it at first. This option will crunch images and remove parts of the PDF that are not needed, in a similar method of a jpeg images. There are slight problems with this method. Images turn out horrible and lose all quality. However for text and simple bands of colour it is perfect, and the reduction in file size can be massive.
Hopefully these two option apply to you. The first one, for the most part, doesn’t produce any decent results (one files size was larger) if the original PDF is made in Preview. However the second option always reduces the files size, usually by half.
If you have any other PDF compression tips, please leave a comment below.