histogram from an image

Hello,

I'm trying to make a one dimensional histogram (frequencies) of the grey levels of a JPEG image. I can't figure out how to access the pixel values of the image. Can someone point me in the right direction?

Thanks,
Roger

ROOT 5.20/00 (trunk_at_24524, Oct 01 2008, 15:00:00 on linux) Received on Thu Jan 29 2009 - 15:59:28 CET