VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Thu Apr 17 2008 - 16:38:16 CDT

Hi,
  You can increase the encoder bitrate, that's the main MPEG-1
parameter one can adjust to get better quality. Beyond that the
best way to achieve better quality is switch to an MPEG-2 based
video encoder. We use ppmtompeg in VMD just because it's free,
it's available on lots of platforms, and the MPEG-1 movies play in
things like Powerpoint without installing any additional codecs.
I'm planning to add support for a few other movie encoders in the
next version of VMD.

Cheers,
  John Stone
  vmd_at_ks.uiuc.edu

On Thu, Apr 17, 2008 at 12:40:15PM -0700, Anthony Ivetac wrote:
> I am using the VMD Movie Maker plug-in with VMD 1.8.6 to generate MPG movies
> of simulation trajectories. Behind the scenes, the TCL script uses PPMTOMPEG
> to stitch the individual PPM images into an MPG file and I am wondering
> which settings in the PPMTOMPEG parameter file (.par) can be toggled to
> achieve better quality movies (presumably at the expense of compression)? I
> find that, with the default settings, the output MPG movie is rather
> 'grainy'.
>
> Many thanks! 

-- 
NIH Resource for Macromolecular Modeling and Bioinformatics
Beckman Institute for Advanced Science and Technology
University of Illinois, 405 N. Mathews Ave, Urbana, IL 61801
Email: johns_at_ks.uiuc.edu                 Phone: 217-244-3349
  WWW: http://www.ks.uiuc.edu/~johns/      Fax: 217-244-6078