simplified creation of animation movies from simulations with LAMMPS-ICMS

hi everybody,

just wanted to let you know that i just committed a set of patches to
the LAMMPS-ICMS branch that implements a "movie" dump style that is
similar to dump image, only that rather than generating individual
images, it will automatically convert them using the FFmpeg tool into
mp4/avi/mpg/mov movies.

you can use the dump movie command pretty much the same way as dump
image. for it to work, you need to have the ffmpeg command line tool
installed and compile LAMMPS-ICMS with the
-DLAMMPS_FFMPEG flag. the precompiled linux rpms and windows installer
packages with the time stamp newer than 20131103 will include that
feature automatically. the windows installer packages already contain
a bundled ffmpeg executable, so they should be working out of the box.

the patches have been submitted to be included to the upstream LAMMPS
version, but i am asking folks to try it out now in order to have
additional feedback and get to know about remaining portability
issues. since ffmpeg is called as an external executable, it should be
limited, but there are also the question of which additional feature
of ffmpeg should be exposed to the dump movie style.

thanks in advance,