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1. INTRODUCTION
Digital processing of multispectral scanner images namely ERTS-MSS
scenes has supplemented all other image processing activity at the
German Aerospace Research Center. To process these pictures a new
and fast system has been installed, which will be used mostly in
an interactive mode, i.e. the user observes the processing on a
screen and decides which steps to be taken to reach his specific
classification goal. Going back and forth between pictorial and
statistical information on different parts of the image enables
him to find his way in a pictorial environment consisting of more
spectral bands than his eyes can perceive.
2. THE IMAGE PROCESSING SYSTEM "DIBIAS"
Installation of the image processing system DIBIAS (DIgitales
BIldAnalyse System) started in March 1974. With a delay of a few
months, mainly due to late delivery of subsystems and to a syn
chronization problem when transferring pictures from digital tape
to a drum type scanner, the first ERTS frames have been written on
black and white photographic paper in August 1974. The results pre
sented in this paper are therefore not as advanced as we had intended
them to be.
Our system is centered around a fast semiconductor memory minicompu
ter with 48 kbyte of memory at the present stage (Fig. 1). Two 800
bpi, 45 ips tape transports allow playback of ERTS Computer Compa
tible Tapes and storage of our program sources. A system's teletype
and a TTY compatible CRT allow (almost) independent program develop
ment and image processing at the same time. The serial matrix printer
is also used to produce numerical printouts of the images. We envi
saged converting it to a fully graphic machine but restrained our
selves because of the heavy mechanical troubles. (It would have pro
duced black and white pictures some 700 picture elements wide -
just the size to print ERTS classification results.) The image out
put is on a drum type facsimile machine, which produces pictures of
DIBIAS DFVLR OBERPFAFFENHOFEN