THE EROS DATA CENTER: A PARTNER IN INTERNATIONAL REMOTE SENSING 
Glenn H. Landis 
Deputy Chief, EROS Data Center 
U.S. Geological Survey 
Sioux Falls, South Dakota 57198 
Introduction 
The United States Department of the Interior's EROS Data Center is 
assuming an expanded role in support of the Landsat system within the 
U.S. and is planning to increase its support of the international 
community of Landsat data users in cooperation with the ground station 
operators throughout the world. 
Improved Data Processing 
The Data Center is entering into a partnership with the National 
Aeronautics and Space Administration to implement an improved system 
for processing Landsat data. The system will provide products with 
superior radiometric and geometric properties and will allow us to be 
more responsive to users requirements in data formatting and timeliness 
of delivery. 
The total system is composed of two elements, one being installed at the 
Goddard Space Flight Center (GSFC) and the other at the EROS Data Center 
(EDC). Frequently the two elements are described as separate systems 
called the Image Processing Facility (IPF) for the GSFC element and 
EROS Digital Image Processing System (EDIPS) for the EDC element; 
together they work as a single system with an interface of high density 
digital tapes between the elements. 
The IPF at GSFC assembles the data acquired by the three U.S. receiving 
Stations, merges the raw data with ephemeris, altitude, sensor calibration 
and ground control point data to Produce a radiometrically and 
geometrically corrected output product. The standard tape transmitted 
to EDC will contain data geometrically adjusted to fit a Hotine Oblique 
Mercator (HOM) projection using a cubic convolution resampling algorithm. 
The EDC element of the system further processes the data that are 
received on the high density digital tape, applying selectable radiometric 
manipulation algorithms to image data, and producing film and computer 
compatible tapes for distribution to users. For reasons of economy, 
EDC's basic strategy is to "pipeline" process all data to 1:1,000,000 
black and white film for archiving and use for photographic reproduction. 
This enables us to continue to offer standard photographic products at 
existing prices. Initially the radiometric manipulation for the standard 
product will be limited to a contrast stretch algorithm that spreads the 
brightness values in each band to the useable density range of the film 
used for recording. Edge enhancement algorithms will not be routinely 
applied. As we learn more about user reaction to the product, the 
processing parameters may be modified.