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Adobe Acrobat SDK
Adobe® Supplement to the ISO 32000
KEY
GPTS
LPTS
Geographic Coordinate System Dictionary
A geographic coordinate system (GEOGCS) specifies an ellipsoidal object in geographic coordinates:
angular units of latitude and longitude. The geographic coordinate system can be described in either or
both of two well-established standards: as a numeric EPSG reference code, or as a Well KnownText (WKT)
string, which contains a description of algorithms and parameters needed for transformations.
Table 8.111b lists the entries in a geographic coordinate system dictionary. A geographic coordinate system
dictionary may be a value of the
on
page
50.)
KEY
Type
EPSG
WKT
Either an
implementation note E-20,
The EPSG reference codes are described in a database available through www.epsg.org, as administered
by the International Association of Oil and Gas Producers (OGP). Well Known Text is specified in document
01-009, OpenGIS Implementation Specification: Coordinate Transformation Services, of the Open Geospatial
Consortium. (See Bibliography.) See implementation note E-9,
TABLE 8.111a Additional entries specific in a geospatial measure dictionary
TYPE
array
array
GCS
TABLE 8.111b Entries in a geographic coordinate system dictionary
TYPE
name
integer
ASCII string
code or a
string is required in a geographic coordinate system dictionary. (See
EPSG
WKT
page
VALUE
(Required; ExtensionLevel 3) An array of numbers taken pairwise,
defining points in geographic space as degrees of latitude and
longitude. These values are based on the geographic coordinate
system described in the GCS dictionary. (Note that any projected
coordinate system includes an underlying geographic coordinate
system.)
(Optional; ExtensionLevel 3) An array of numbers taken pairwise that
define points in a 2D unit square. The unit square is mapped to the
rectangular bounds of the viewport, image XObject, or forms
XObject that contain the measure dictionary. This array contains
the same number of number pairs as the
pair is the unit square object position corresponding to the
geospatial position in the
or the
entry of a geospatial measure dictionary. (See Table 8.111a
DCS
VALUE
(Required; ExtensionLevel 3) The type of PDF object that this
dictionary describes; shall be
system dictionary.
(Optional; ExtensionLevel 3) An EPSG reference code specifying the
geographic coordinate system.
(Optional; ExtensionLevel 3) A string of Well Known Text describing
the geographic coordinate system.
See implementation note E-8,
132.)
Interactive Features (Chapter 8 in PDF Reference)
8.8.1 Geospatial Features
GPTS
array.
GPTS
for a geographic coordinate
GEOGCS
page
131.
page
131.
51
array; each number
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