as the title says I want to change background of a PDF. This are some slides, and to save toner I thought it would be good to change the background to white. I tried pdftk with its operations: background and stamp, but the don't work as expected:
pdftk old.pdf background white.pdf output out.pdf pdftk old.pdf stamp white.pdf output out.pdf
I also tried convert (bloating my pdf upto 200MB) as done this way:
convert old.pdf -background white new.pdf
with no luck. Do you know a way I could perform this?