Kolam is a software package for interactive visualization of massive geospatial datasets and 2D imagery on standard desktop and mobile computers. Kolam is a platform and operating system independent software developed at the University of Missouri, that also takes advantage of commodity high performance graphics processors or GPUs. Kolam supports embedded datasets at multiple resolutions ranging from one km global to 30cm urban mosaics that may be hundred of gigabytes to terabytes in size. Such large datasets are too large to fit entirely in the main processor memory of inexpensive computing platforms. A new multiresolution tiled pyramid file layout structure combined with a quad-bundle memory data structure is used to enable interactive display.
In addition to extremely rapid roam, zoom and hyper-jump spatial operations, Kolam supports an arbitrary number of simultaneously visible embedded layers,
on-the-fly colormap lookup and histogram enhancement, projection of images onto a spherical surface and elevation maps or terrain rendering. Kolam was originally developed in 2001 and either predates or was cotemporaneous with the currently popular satellite imagery plus map web services from Google Earth (i.e. Keyhole), MSN VirtualEarth, Microsoft Terraserver, Terrafly, etc.
DOCUMENTATION
Ian Roth's Thesis Document (PDF format, ~11.5 Mb)
Thesis Presentation (MS PowerPoint format, ~4.0
Mb)
The ever-increasing size of spatial datasets in a variety of
applications such as remote sensing and scientific visualization requires the
development of new data structures and software tools for efficiently managing
and manipulating very large datasets. The new generation of sensors, instruments
and numerical models combined with enhanced computational capabilities, produce
datasets that are many times larger than the physical computer memory available
to view that data. Individual simulations in computational fluid dynamics are
now 300 GB in size for which highly interactive browsing combined with automatic
feature extraction is desired for understanding complex phenomena (Bryson et al.
1999). How does one ensure interactivity when loading a 100 GB dataset into
memory can take up to an hour even with high-performance hardware. Another
example from remote sensing is to interactively browse a Landsat mosaic of the
Unites States (US). A multispectral (6 band) Landsat TM mosaic of the
conterminous US at 30 m resolution, requires 428 scenes (single coverage) and
results in an image with dimensions of 218,000 x 95,000 pixels that uses 160
gigabytes (GB) of storage space at multiple resolutions (Plesea and Curkendall
2000). This mosaic was created at the NASA Jet Propulsion Laboratory, and was one
of the largest seamless single images at that time; JPL has now produced a global
(pan-sharpened) 15m resolution Landsat 7 ETM+ that is about 4TB in size and
can be accessed at WMS Global Mosaic.
Strategies for dealing
with large datasets for scientific visualization include sparse traversal and
compression (Bryson et al. 1999). Methods for viewing large digital imagery
using tiling and discrete wavelet transform (DWT)-based compression are
described by Bradley (1998), Hovanes et al (1999) and Diego et al (2000).
Furthermore, extremely large datasets often reside on a remote computer system
and hence require integrated support for network access to view and manipulate
this data. The objective of Kolam is to design a system for interactively
viewing large datasets that not only exceed available memory resources but
potentially exist only in the secondary storage of a remote system such as a
digital library. We will refer to this software as kolam (K-tiles for Optimized
muLtiresolution Access with coMpression). REFERENCING SOFTWARE
Kolam was written by Joshua Fraser, Ian Roth and Prof. K.
Palaniappan, University of Missouri-Columbia. The current version is maintained by Joshua Fraser. References:
Palaniappan K, Fraser JB (2001) Multiresolution tiling for
interactive viewing of large datasets, Seventeenth Int. Conf. on Interactive
Information and Processing Systems (IIPS) for Meteorology, Oceanography and
Hydrology, Jan. 14-19, 2001, Albuquerque, NM, AMS, 2001, pp.338-342. Kolam is under continuous development. Please refer to our
web page (http://meru.cecs.missouri.edu/mvl/kolam) for the latest version,
additional information, and resources. SOFTWARE OVERVIEW & USER MANUAL
Executable Binaries:
SAMPLE DATASETS (pyramid file format)
ABSTRACT

Zipped AVI Movie (~3.7 Mb)
Joshua Fraser - fraser@meru.cecs.missouri.edu
Ian Roth - ijr3d2@meru.rnet.missouri.edu
K. Palaniappan - palani@cecs.missouri.edu