Re: Newbie question about VisAD and large datasets

• To: "Cunningham, Daniel" <cunninghamd@xxxxxxxx>
• Subject: Re: Newbie question about VisAD and large datasets
• From: Bill Hibbard <billh@xxxxxxxxxxxxx>
• Date: Fri, 16 Apr 2004 14:12:58 -0500 (CDT)

Hi Daniel,

> I am considering using VisAD to develop some neuroimaging applications.  I
> was curious as to how well VisAD deals with large datasets.  For example, a
> 16 bit dataset with dimensions 64 x 64 x 24 x 576 is what I consider to be
> large.
>
> If anybody has experience using data of this size or larger, please comment.

64 * 64 * 24 = 98304 which is quite easy to deal with as a
volume of data. However, 98304 * 576 = 56.6 M, which will
be a big challenge for Java3D (and hence VisAD) unless you
have a version utilizing a 64-bit architecture (these days
several GB of RAM is quite reasonable, but there is a problem
finding Java implementations that can use it).

I think Curtis Rueden has some experience with very large
data sets in his VisBio application (I think with data sets
a lot like yours), and has come up with some clever work
arounds for memory issues (e.g., multi-resolution
rendering). He and I discussed the possibility of a custom
DataRenderer for dealing with long time sequences of images
(I assume your 576 is a time count), although I understand
its not his highest priority. Perhaps he will comment.

Gooc luck,
Bill

• References:
  • Newbie question about VisAD and large datasets
    • From: Cunningham, Daniel