We have had the best results putting line-art animations
on the web using GIF format. Typical video compression schemes do poorly
because they are designed for photographic images--they result in large file
sizes and poor quality when used with circuit animations. Another format
that can be expected to work well is MNG (
Multiple-image Network Graphics
), based on the corresponding PNG (
Portable Network Graphics
) format.
The process we have used works as follows. We save graphics from MATLAB
to an uncompressed avi file (because the available compression schemes don't
work well). Then we use
GIF Contruction Set Professional
, an inexpensive shareware program by
Alchemy Mindworks
, to convert to GIF and compress the files. Alchemy Mindworks'
PNG/MNGContruction Set Professional
should work similarly for MNG animations. The detailed process is
outlined below
Please
email me
a link to animations you create, so that we can put a link to it on the
page of
animations
on-line
.
Step-by-step instructions for putting animations
on the Web.
- Modify the m-file for the circuit you wish to animate by using
saveanimation(....) in place of canimate(...), using the same
arguments. A nice way to do this is to add an optional input argument
save that is omitted to run the animation directly, or set to one to
save it to disk, as in this code, which assumes three other input arguments
before save.
if nargin<4, save = 0; end % Sets it up to not
save anything if save has not been specified.
if save
saveanimation(t,vm,cvm,im,ca,ia,rate,switchm);
else
canimate(t,vm,cvm,im,ca,ia,rate,switchm);
end
Do not loop the animation yet--the file will be big enough (10s of MB) without
looping!
- Run the animation and select a file to save to. The code is
set up to save a maximum of 100 frames in a single file, and to prompt you
for a new filename if the animation runs more than 100 frames. This
is to keep the file sizes manageable. If you run this on a machine with
plenty of memory, you may be able to change this and use larger files--change
the variable maxframes in saveanimation. It is recommended
that you leave the figure window active and not run other applications while
saving the animation; otherwise bits of other images can get in the file.
- Launch GIF Construction Set Professional. You may wish to
quit MATLAB and other programs first, as this process will require a lot
of memory
- Convert your avi file to gif from the 'File: Movie: Movie to GIF'
menu item. Select loop if you wish for it to loop. Save the GIF
file and repeat for each 100-frame file if your animation has been broken
into multiple files.
- Merge the multiple files together. Start by opening one, and
positioning the insertion point where you want to add the others (typically
at the end of the sequence). Select 'Merge' from the 'Block' menu to
add the frames from another file. Repeat for as many files as the animation
has been broken down into.
- Select the 'Supercompress' option from the file menu to compress
this merged file.
- The animation can then be placed on the web. It is helpful
to put an html 'wrapper' on it, because some web browsers (e.g., Internet
Explorer) may open a GIF file using a still image editor rather than displaying
the animation in the web browser, if given the GIF file in the URL directly,
rather than being pointed to an html page that containts the image.
- Send me
a link to your animation, so that we can put a link to it on the page of
animations on-line
.
Back to
circuit
animations toolbox instructions and download
or
3D circuits homepage
, or jump to
animations
on-line , or to
background
information
.
For comments or questions email:
Charles.R.Sullivan@dartmouth.edu
This page last updated on June 9, 2002
© 2002