[xwiki-users] Selected pages of PDF to image conversion in XWiki?

Hi! The task is: - Calculate MD5 of attached PDF document - Extract e.g first 10 pages from the attached PDF file as images - store images as attachments into the document 1. What is the best way to calculate MD5 in XWiki? Is it possible to do via standard velocity scripting in XWiki? 2. Is there any built in/hidden ways of PDF->image conversion of several pages of attached PDF file? If not, what is the solution possible? I found some opensource JAVA libraries, but I realize a big gap in my understanding between libraries and their integration in XWiki with followng velocity scripting usage. Does anyone has a clue where to dig to make all this staff runnung? Thanks in advance, Dmitry