Hello folks!

I need to develop a program that'd match two signatures..i know of course it already exists but i've been told to make it again by my prof. she probably wants to see my coding..
anyway, i'm a beginner and i'll work hard to do it..but i need some guidance..

just tell me what library should i use? in the start, i just want to tally two signatures(pictures scanned through a scanner)...
as i go advanced and move to matching two signatures input via an electronic signature pad, i'd need to match speed and pressure as well..

just show me the correct way..the correct library!!