apply pixel mask

This is going to be an on-going post about making this piece of code run, . I'm just going to add to it bit-by-bit until I have something complete. Usually the first thing to check is:

setenv LD_LIBRARY_PATH /usr/local/lib/

in your .cshrc. There are other steps required, but on my current libraries, installed on a new machine, this is the thing I forget to add most often. /usr/local/lib is where I usually keep all the needed C/C++ libraries, but it certainly change if you move to other machines.