From: Axel Kohlmeyer (
Date: Sun Dec 04 2011 - 23:27:48 CST

as an example, you may want to check out the two videos featured
on this page.
they are available in up to 720p (HD) format and were created with
Tachyon on a cluster using the outlined procedure with ffmpeg
in 1080p with suitably high video data rate (they were postprocessed
by youtube for reduced storage/data rate).


On Mon, Dec 5, 2011 at 12:19 AM, Axel Kohlmeyer <> wrote:
> On Sun, Dec 4, 2011 at 10:35 PM, David Cohen-Tanugi <> wrote:
>> Dear All,
> dear david,
>> What are the most effective ways of rendering high-quality and long movies
>> from VMD trajectories?
>> I have been using VMD to visualize long (1000+ frames) trajectories of
>> molecular dynamics simulations from LAMMPS, and I haven't yet found an
>> efficient way to render these trajectories into high-quality videos. My
>> Macbook Pro is quick enough for most purposes but at 2-3 minutes per frame
>> in Tachyon Internal with ambient occlusion, it seems much more logical to
>> export the job to a parallel cluster on many nodes.
> sure, and it is a fairly straightforward thing to do.
>> In that context, what is the most straightforward and efficient way to
>> render and encode a very long, high-quality movie from a VMD session?
>> Strategies that leverage parallelized cluster computing would be greatly
>> appreciated!
> the general strategy would be to do visualization, rendering, and
> movie generation as separate steps. for the visualization, you
> can create input files for Tachyon from within VMD through a
> loop construct. those can then be transferred to a cluster (or
> you can use a previously saved state and generate the render
> inputs directly on the cluster) and then rendered into individual
> pictures in batch mode. Tachyon can be compiled for threading
> or MPI parallelization on top of that you can parallelize over the
> individual input scripts (but it is usually more effective to bundle
> multiple inputs into a single submit script). if you are limited by
> disk space, you may want to compile Tachyon with jpeg support
> or convert the default TGA format files into high-quality (85-95)
> jpeg files. the final step would be to convert the individual
> image frames into an mpeg/quicktime/divx/avi/mp4/whatever
> format movie with your favorite tool.
> this will require some custom scripting, but a lot of the required
> script code is either straightforward to write from scratch or can
> be adapted from the vmd movie maker plugin.
> for the quality setting, you should take into account the image
> and quality loss through the video compression (depending on
> the selected video data rate), which benefits from avoiding hard
> contrasts, "pure" colors (especially red) and smoothing/antialiasing.
> HTH,
>    axel.
>> Many thanks,
>> David
>> David Cohen-Tanugi | Ph.D. Candidate | Jeffrey C. Grossman Group |
>> Massachusetts Institute of Technology | Department of Materials Science &
>> Engineering | 609-902-6850 | |
> --
> Dr. Axel Kohlmeyer
> College of Science and Technology
> Temple University, Philadelphia PA, USA.

Dr. Axel Kohlmeyer
College of Science and Technology
Temple University, Philadelphia PA, USA.