Comparing PDF files

Dustykitten

I have been asked by somebody even less techie than I am if I can compare 2 PDF files for them.


They are 2 versions of the same thing and we need to know what the differences are. The files are large so I need to know if there is some way that the computer can do this rather than us try to do a spot the difference challenge.

Can anybody tell me if this is feasible?

Many thanks

asbokid

well obviously a comparison of the file size is a starter..

then an md5sum checksum comparison..

other than that, you're stuffed.

pdfs which contain the same textual information can be encoded in an infinite number of ways, none of which can be compared except by human hand.

you could strip out the text formatting and compare on text content alone, but it probably wouldn't be very satisfactory.

RussJK

You could try using Calibre, and as above convert the PDFs to a text file. After that, search for some of the many freeware programs designed to compare text files. Only download from a safe site of course.

Stompa

Well there are products like:

http://www.pdfanalyzer.com/

(found by Googling, so I've no idea whether it's good, safe, etc...)

Looks like you get 5 tries with it before you have to pay.

RussJK

Stompa wrote: »

Well there are products like:

http://www.pdfanalyzer.com/

(found by Googling, so I've no idea whether it's good, safe, etc...)

Looks like you get 5 tries with it before you have to pay.

You could install Sandboxie (worth it alone for the security it offers), then install and run PDF Analyzer under the Sandbox.
http://www.sandboxie.com/

Using a Sandbox will protect you if the file contains a trojan.

If you were that way inclined, you theoretically could just delete the sandbox after the 5 tries and re-install it inside the sandbox for a new set of 5 tries.