I've tried watermark type tricks to superimpose one page with another, but failed. The pages seem to be raster based, with no transparancy.
Each is nearly identical to the next with only minor differences. I only care about the top 50% of each page. I dont want to waste paper and toner by printing the whole page. I'd like to:
Start with page 1 cut the page in half throw away the bottom half
Take page 2 cut the page in half throw away the bottom half
Glue whats left of page 1 and page 2 one on top of the other.
repeat with pages 3 & 4, etc
This way I will end up with half the pages, and only the information I care about. This is a process that would get repeated multiple times a day, so a GUI based solution is not acceptable.
I've tried several free and open source libraries, and have not met with complete sucess. I'm open to any free or open source solution that will work on a Windows 7 x64 machine.