For a rails app that works a lot with uploaded image heavy pdf files I'm looking for a way to optimize the file size of uploaded pdf's.
Adobe Acrobat has a 'save as reduced file size pdf' option which often halves the filesize when images are included.
I would like to do a similar action that is triggered after a file upload in my rails app.
Any ideas?
While @lzap's comment may be true, if you still want to give it a shot, you might look at pdftk (PDF Toolkit). Its a library for manipulating and creating PDF files that looks like it offers the ability to compress a given pdf file.
The library can be installed on most major operating systems, so if you have the ability to install it on your host, then simply call:
system("pdftk uncompressed-input.pdf output compressed-outpu.pdf compress")
inside your rails app whenever you want to compress a particular PDF file. I have no idea how long this would take, and if you are compressing many PDF's at the same time, you may want to consider handing off to a background job (without this, Rails will wait until the compression is done before returning anything to the browser, probably causing a timeout error for long running groups of compression calls).
Also, if your file names come from user input, be extra careful to avoid injection attacks.
