278 
GRAPHICS 
REPROMAT 
MAPS 
COLOR 
SCANNER 
AGDS 
^ SCAN 
VECT 
^ V, 
DCS 
Jd4 
DCAD 
SLF 
MT 
5k. 
GLSS 
7K 
CCRS 
~7TT 
DIRECT 
PRINTING 
7TC 
AES 
(GLSS) 
LPM 
CAP! 
/TC 
PHOTO 
SOURCE 
Figure 2. Proposed Production Scenario 
DATA BASE REQUIREMENTS 
Regardless of the complexity of the above mentioned production processess, the 
creation of an off-line Digital Cartographic Applications Data Base remains as 
one of the largest hurdles to be overcome prior to implementation of an 
effective Automated Charting production process. The many systems within 
the proposed production process of Fig. 2 would currently be limited in their 
effectiveness for lack of a common standard format which would allow data 
exchange between those systems not directly interfaced. DMA is developing 
such a Standard Linear Format (SLF) for efficient interchange of digital data. 
Such a format could be the logical basis for DCAD, and for this paper, DCAD 
and SLF will be synonymous. It is also anticipated that the DFAD specification 
will be expanded to include additional features (roads, streams, etc.) such that 
ATM charting requirements will be supported by this specification. 
In the past, the charting, DTED, DFAD and DVOD programs have been separate 
and legitimate programs because each had its own requirement and production 
schedule. Resources (hardware and manpower) were not available for efficient 
and even practical exchange of data. Also, each program had the potential to 
use different sources and control. As a result, commonality problems could and 
often did result. 
Typically though, DMAAC requirements for charting, DFAD, DTED and DVOD 
could all be derived from the same basic control and source materials. The 
CAPI system is expected to provide this capability to achieve all four 
requirements in a single pass. It would produce common data elements, to the 
extent practical, in terms of cost and time available, when digital data is 
required to support multiple products over the same geographic area. Such a 
production process would capitalize on redundent production requirements, 
provide source and product commonality and subsequently minimize a 
proliferation of production and maintenance software. Long range combination 
of functions will lead to improvements in quality and reduced cost. Short range 
costs would be high as the transition takes place, but benefits in product 
quality/compatibility are expected with initial production. 
DCAD has two basic design objectives: 
1. To store a string of data only once, no matter how many features it may be 
a part of (segment/node format). 
2. To accommodate multi-product and multi-series charting requirements.