Re: Best Movie/Animation Format for LARGE files

[thompson(at)orpheus.nascom.nasa.gov (William Thompson)]

wcapehar@my-deja.com writes:

>In article <88rm7q$qqa$1@pukkie.phys.uu.nl>,
>  P.Suetterlin@astro.uu.nl wrote:
>> In article <MPG.131a56a6dc21d88e989a3b@news.frii.com>,
>> 	davidf@dfanning.com (David Fanning) writes:
>>
>> >> I have been working on some large image time series (long in time and
>> >> large in size) and am wondering what the best format (jpeg/mpeg) for
>> >> saving them with the least distortion to the frames.
>>
>> >> Ideas? (I'm already breaking up the time series into smaller clips.)

>> > I've been getting reports--John Broccio's article today is
>> > only the latest--of poor resolution when making MPEG movies.

>> I had one try at the built-in MPEG creation of IDL and immediately
>> dumped it.  I'm creating my mpegs using mpeg_encode (Version 1.5).

>> You have to store the single frames on disk, so no memory
>> limitations.  Of course mpeg (and jpeg, too) are lossy compression
>> tools, I only use them if I only want to look at them, and don't
>> intend to do (e.g.) photometric work..

>> PS: That's under Unix.  Not sure, but mpeg_encode might also compile
>>     under other OS.


>I agree with the degradation issue.  Small mpeg movies (in time steps
>and in the image sizes) are fine but larger ones, tend to "coarsen up."


I wonder if the larger movies "coarsen up" to be compatible with Microsoft
Windows mpeg players.  We've been making MPEG movies on our Unix workstations
using mpeg_encode for some time now.  The movies always play well on our
workstations, but sometimes the movies don't play correctly on Windows
machines.  This problem has always been attributed in the past to the size of
the individual frames.  However, recently I was told that a movie which
wouldn't play in Windows in its original format, was made to do so when it was
regenerated at the same frame size, but with a lower quality parameter.  The
current theory is that Windows players refuse to play MPEGs unless they can
decode them fast enough to play the frames at the correct frame rate.

William Thompson