Open PDF file and how to compare diagrams in pdf file with other pdf file

I want to compare two pdf file in which there are some figures and diagrams like graph and circles .How can I do that . PDF checkpoint is checking the text only and validate it but what about figures .
Also i want to open PDF file which has saved in a folder .How to do that.

Its a desktop application and i am doing keyword testing using record and play
MarshaT