STANDARDIZATION OF REMOTE SENSING AND GIS DATA TRANSFER 
Fred C. Billingsley W. Murray Strome 
Jet Propulsion Laboratory Perceptron Computing Inc, 
California Institute of Technology DOWNSVIEW, Ontario 
PASADENA, California, U.S.A. Canada 
INTRODUCTION 
During the past two decades, the use of digital imagery and other remotely 
sensed digital data has grown dramatically in many disciplines. This growth 
has been possible because of parallel developments in digital image 
acquisition, computer processing capability, storage media, transmission 
link capabilities and image display technology. The increasingly widespread 
availability of the data has encouraged the investigation of world size 
problems, in turn calling for more global data. Both remotely sensed and 
ground based data are increasingly being used together, making more critical 
the ability to interchange data files from the disparate sources. 
Ease of digital data interchange and use is controlled by two factors, 
representing two possible approaches: the similarity of files of similar 
data (the common format family approach) and the ability to describe the 
files adequately to allow machine receipt and processing vith a minimum of 
human intervention or special logging programs (data definition language 
approach). The two approaches are complementary. 
MODELLING THE PROCESS 
The transfer of data can be modelled generically by several elements as 
follows: 
a) Source Information 
b) Data Form 1 
c) Data Form 2 
d) Transfer Process 
e) Data Form 2 
f) Data Form 3 
g) Received Information 
It is desirable to develop two concepts: 1) the separation of the transfer 
process into two layers pertaining to the generic description of whatever 
data is being transferred and the organization of that data to suit the 
discipline involved; and 2) the differentiation of the data structure 
reference from the data structure definition. 
Using the elements listed above, the intent is to convert the source data 
(Form 1) to a Standard Interchange Format (Form 2) which will convey the 
formatted data items, schema transfer information and topology transfer 
information from a source to a target data base (Form 3). The source is 
transported from its resident hardware configuration to become the target 
data base on a potentially different computer. The transfer should result 
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