ISO 14825:2011

INTERNATIONAL ISO
STANDARD 14825
Second edition
2011-07-15
Intelligent transport systems —
Geographic Data Files (GDF) — GDF5.0
Systèmes intelligents de transport — Fichiers de données
géographiques (GDF) — GDF5.0
Reference number
©
ISO 2011
©  ISO 2011
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ii © ISO 2011 – All rights reserved

Contents Page
Foreword .vi
Introduction.vii
1 Scope .1
2 Normative references .1
3 Terms and definitions.2
3.1 General terms.2
3.2 Mathematical terms .3
3.3 Geodetical terms.4
3.4 GDF terms.6
4 Symbolization and notation elements .9
4.1 GDF symbolizations .9
4.2 UML notation .9
5 Overall conceptual data model.15
5.1 Conceptual data models in GDF.15
5.2 The general data model of GDF.15
5.3 The Attribute model .24
5.4 The Relationship model .27
5.5 Linear referencing.27
5.6 The Feature representation scheme .28
5.7 Time modelling.28
5.8 Data management: organisation of Feature data into Layers and Sections .29
6 Feature Catalogue.33
6.1 Generic specifications.33
6.2 Roads and Ferries.34
6.3 Administrative Areas .51
6.4 Named Areas .59
6.5 Land Cover And Use.63
6.6 Terrain Elevation.93
6.7 Structures .98
6.8 Railways.99
6.9 Waterways .100
6.10 Road Furniture .104
6.11 Services .107
6.12 Public Transport.108
6.13 Linear Referencing Features .112
6.14 Linear Datum Features .114
6.15 General Features.116
7 Attribute Catalogue.118
7.1 Generic specifications.118
7.2 Attributes .166
8 Relationship Catalogue .314
8.1 Generic Specifications .314
8.2 Relationship Types .342
9 Feature representation rules .387
9.1 Generic specifications.387
9.2 Roads and Ferries.403
9.3 Administrative Areas .406
9.4 Named Areas .408
9.5 Land Cover And Use .409
9.6 Terrain Elevation .410
9.7 Structures.410
9.8 Railways .413
9.9 Waterways.414
9.10 Road Furniture.415
9.11 Services.415
9.12 Public Transport.415
9.13 Linear Referencing Features.416
9.14 Linear Datum Features .416
9.15 General Features .417
10 Metadata Catalogue .418
10.1 Generic specification .418
10.2 Headers and terminators.420
10.3 Data Dictionary .436
10.4 Table of Contents .448
10.5 Source Material.453
10.6 Geodetic Parameters .459
10.7 Update Information .468
10.8 General Comment .468
11 Logical Data Structures .469
11.1 Introduction.469
11.2 Logical GDF Album .474
11.3 Datasets.476
11.4 Layers.500
11.5 Sections.501
11.6 Time Domain Syntax .519
11.7 Update Information .530
11.8 Common Data Types.532
12 Media Record Specifications .541
12.1 General specifications .541
12.2 Field specifications .555
12.3 Additional Constraints for Topological Features.598
12.4 Additional Constraints for Non-Explicit Topological Features: Order of Coordinate
triplets in Feature Records.599
12.5 Mandatory Records.599
12.6 Record Format Specifications: Global Records .599
12.7 Record Format Specifications: Data Records.650
12.8 Record Format Specifications: Update Information Records .684
13 XML schema specifications .687
13.1 Introduction.687
13.2 Data content.691
13.3 GDF XML schema.693
13.4 Schema GDF_Main.xsd.694
13.5 Schema GDF_data_dict.xsd.758
13.6 Schema GDF_userDefined.xsd.945
14 SQL encoding specifications.950
14.1 SQL design.950
14.2 Data content.953
14.3 Topology Type.978
14.4 Data partitioning.980
14.5 General GDF data .1018
14.6 Features.1022
14.7 Relationships.1059
14.8 Attributes.1063
14.9 Object Referencing .1071
iv © ISO 2011 – All rights reserved

14.10 Update registry.1074
14.11 Abbreviation .1080
14.12 Entity/Table indexes .1081
14.13 Entity Relationship diagram conventions .1086
14.14 SQL/MM base tables for Topology and Network .1095
Annex A (normative) Semantic codes.1099
Annex B (informative) Metadata codes.1127
Annex C (informative) Services .1165
Annex D (normative) Syntax for Time Domains.1173
Annex E (normative) Sectioning GDF Datasets .1195
Annex F (informative) Rules for the formation of Level 2 Features from Roads and Ferries .1198
Annex G (informative) Geopolitical Structure examples.1208
Annex H (informative) Specification of possible use of notation and phonetic Attributes for
character strings.1226
Bibliography.1229

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 14825 was prepared by Technical Committee ISO/TC 204, Intelligent transport systems.
This second edition cancels and replaces the first edition (ISO 14825:2004), which has been technically
revised.
vi © ISO 2011 – All rights reserved

Introduction
By the late 1980s, producers and users of digital road map data became increasingly aware of the need for a
common data interchange standard. Lack of such a standard was seen as an impediment to the commercial
growth and success of industries using such data. Before the advent of the Intelligent Transport Systems (ITS)
industry, development of spatial data interchange standards was done mostly on a regional basis and not
designed for the specialised requirements of road-transport-related applications. The establishment of
ISO/TC 204 in 1993 sought to remedy the lack of international standards for ITS. The technical committee is
divided into 16 working groups. Working Group 3 (WG 3) was charged with the responsibility of developing
standards to promote interchangeability of map data and interoperability of systems using map databases.
The work of WG 3 started in 1994 with a review of the available regional standards documents, including
standards developed by the Japan Digital Road Map Association (JDRMA) and developments in the US that
resulted in the Spatial Data Transfer Standard (SDTS). European standardization efforts resulted in a
standard called GDF3.0 (Geographic Data Files), which eventually was adopted as the basis for
internationalized developments, leading to the publication of GDF4.0 in 2004.
In the 1990s, the GDF standard was instrumental in enabling the European business-to-business (B2B)
market for in-vehicle navigation in that it provided interoperability for exchanging digital map data between
map manufacturers and navigation system integrators. The GDF specifications provided a base for both the
capturing of geographic content and the exchanging of it. Its original design foresaw a powerful, application-
independent model, while its initial rendition as a standard specifically addressed the requirements for the
richness of navigable map databases. Since then, GDF has evolved in terms of boosted data modelling
capabilities, broadened international applicability, expanded geographic domains, and diversified exchange
formats. As a result, GDF covers a wide range of application domains and has been adapted to many
geospatial technologies
The current document presents the specification for GDF5.0, resulting from approximately 30 rounds of
meetings held between 2001 and 2008 and involving experts from Australia, Canada, the Czech Republic,
France, Germany, Japan, the Republic of Korea, the Netherlands, and the United States of America.
Extensive activities towards harmonization with ISO/TC 211 standards were undertaken. Major GDF5.0
enhancements include UML model migration and refinements, harmonization with linear referencing and
geospatial web standards, support for 3-D content and time coordinates, comprehensive character set and
phonetic representations, and new XML- and SQL-based delivery formats.
The specification of this International Standard is divided into several parts.
After the introductory clauses, the overall conceptual data model is specified. In it, the basic building blocks of
GDF and their interrelations are explained. It contains a specification of the different types of topology
supported by this International Standard. It furthermore describes how database representations of real world
objects, referred to as Features, are defined. It describes the characteristics of Features, called Attributes, and
the topological and non-topological interrelations between Features. Finally, it describes the organization of
the Features in GDF. Semantically, Features are organized in different Feature Themes. Logically and
physically, Features are organized in Sections by area or in Layers by contents.
In the Feature Catalogue, the different Features supported by this International Standard are defined. A
special case is the Features from the Services Feature Theme. Because the requirements for this Feature
Theme are highly market-oriented, the Services Feature Theme does not contain any normative Features, but
contains an annex comprising an informative list of service definitions to assist users of this International
Standard (see Annex C).
In the Attribute Catalogue, the different characteristics of Features, called Attributes, are defined. A usage
matrix outlines applicability of Attributes per Feature Theme and per Relationship.
In the Relationship Catalogue, the different non-topological (i.e. semantic) Relationships which Features can
have are defined. Relationships can relate Features of different Feature Themes, or those from the same or
different Section and/or Layer.
In the Feature representation rules, the possible geometrical ways in which the individual Features can be
represented are specified for each topology type. This International Standard supports zero-, one- and two-
dimensional primitives and up to four-dimensional coordinates.
The specification of Features, Attributes and Relationships by no means dictates mandatory inclusion. The
actual contents of GDF, apart from a minimum set of metadata elements as specified in the delivery formats,
is not specified by this International Standard since this is considered to be an issue between clients and
vendors. This International Standard allows the introduction of user-defined Features, Attributes and
Relationships.
In certain cases, different alternative ways of modelling and representation are offered. Representing Features
in different geographical areas also may require the use of different basic representation mechanisms such as
character sets, projection systems, etc. It is important that all these individual choices associated with GDF
are specified. Furthermore, GDF should essentially be self-contained and be readable without any external
specification. In order to make this possible, this International Standard specifies ways of describing GDF by
means of metadata, captured by the Metadata Catalogue.
Apart from providing a standard for the definition of geographic road databases, this International Standard
also specifies mechanisms for data exchange and delivery. In order to facilitate the definition and exchange of
data, a logical view of the data organization is important. This logical view is presented in the Logical Data
Structures. The data structures are specified using the data description language ESN.
Three physical realisations for data exchange and delivery are specified; the Media Record Specifications
(ASCII flat file), the XML schema specifications, and the SQL encoding specifications. These specifications
support the explicit registration of updated information, thereby allowing map databases to continue to reflect
ground truth over time.
Features, Attributes and Relationships appear in the physical GDF as codes. These codes are specified in
Annex A. Codes used in the metadata are given in Annex B, which is an informative part of this International
Standard. In order to access the most up-to-date information, the user is referred to the original source
organization. Annex C contains the specification of Features of the theme Services as an informative part of
this International Standard. In Annex D, the syntax for specifying temporal aspects of geographic information
is described. The specific rules for organizing GDF in different spatial subdivisions (Sections) is described in
Annex E. As informative parts of this International Standard, guidelines for the formation of Level 2 Features
from the Feature Theme Roads and Ferries are given in Annex F. A list of local Administrative Area names in
different countries is provided in Annex G, as well as illustrative examples for the description of the (non-
hierarchical) geopolitical structures and their components in a number of countries. Finally, the use of notation
and phonetic Attributes for character strings are illustrated in the informative Annex H. Annex H provides a
range of examples showing how the different notation- and phoneme-related Attribute properties can be used
to qualify name strings, in both their written and their pronounced form.
viii © ISO 2011 – All rights reserved

INTERNATIONAL STANDARD ISO 14825:2011(E)

Intelligent transport systems — Geographic Data Files (GDF) —
GDF5.0
IMPORTANT — The colours represented in the electronic file of this document can be neither viewed
on screen nor printed as true representations. For the purposes of colour matching, see ISO 3864-1
which provides colorimetric and photometric properties together with, as a guideline, references from
colour order systems.
1 Scope
This International Standard specifies the conceptual and logical data model and physical encoding formats for
geographic databases for Intelligent Transport Systems (ITS) applications and services. It includes a
specification of potential contents of such databases (data dictionaries for Features, Attributes and
Relationships), a specification of how these contents shall be represented, and of how relevant information
about the database itself can be specified (metadata).
The focus of this International Standard is on ITS applications and services and it emphasizes road and road-
related information. ITS applications and services, however, also require information in addition to road and
road-related information.
EXAMPLE 1 ITS applications and services need information about addressing systems in order to specify locations
and/or destinations. Consequently, information about the administrative and postal subdivisions of an area is essential.
EXAMPLE 2 Map display is an important component of ITS applications and services. For proper map display, the
inclusion of contextual information such as land and water cover is essential.
EXAMPLE 3 Point-of-Interest (POI) or service information is a key feature of traveller information. It adds value to end-
user ITS applications and services.
Typical ITS applications and services targeted by this International Standard are in-vehicle or portable
navigation systems, traffic management centres, or services linked with road management systems, including
the public transport systems.
The Conceptual Data Model has a broader focus than ITS applications and services. It is application
independent, allowing for future harmonization of this International Standard with other geographic database
standards.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 690, Information and documentation — Guidelines for bibliographic references and citations to
information resources
ISO 3166-1, Codes for the representation of names of countries and their subdivisions — Part 1: Country
codes. Codes are available at http://unstats.un.org/unsd/methods/m49/m49alpha.htm
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 General terms
3.1.1
cartographic primitive
atomic construction element in a cartographic representation, i.e. Node, Edge and Face
3.1.2
data file
collection of related data records having a homogeneous structure
NOTE See Reference [34].
3.1.3
data record
record containing Feature-related data
3.1.4
global record
record that logically precedes the data records and contains control parameters, data definition and
documentation necessary to interpret companion data records
NOTE See Reference [25].
3.1.5
Medium Unit
object for data storage that can be considered as a physically undivided whole
EXAMPLE One floppy disk, one magnetic tape, a CD, or a DVD.
3.1.6
multi-media
any kind of data other than conventional data
EXAMPLE Graphic, audio or visual data.
3.1.7
Multi-media Object
piece of multi-media to be processed by an application
EXAMPLE A picture, a text, a movie, or a sound.
3.1.8
repeating Attribute Type
Attribute Type that may have multiple values associated to one and the same instance of a particular Feature
Class
3.1.9
Spatial Domain
description of the limits of a geographical area to which a particular set of data belongs spatially
3.1.10
source material
origin of data in analogue or digital representation, stored on any kind of data medium
2 © ISO 2011 – All rights reserved

3.1.11
topology
field of mathematics that deals with characteristics of geometric structures that are preserved after continual
variation
NOTE See Reference [43].
3.1.12
transcription
rendering of geographic names from a non-alphabetic script into an alphabetic one or vice versa
NOTE 1 See Reference [40].
NOTE 2 The term is also applied to initial recording in script of hitherto unwritten names.
3.2 Mathematical terms
3.2.1
Area Feature
two-dimensional Feature, defined by one or more Faces
3.2.2
Edge
directed sequence of non-intersecting Line Segments with Nodes at each end
NOTE See Reference [34].
3.2.3
enclave
small part of an area enclosed by another area, seen from the area to which that part belongs
3.2.4
exclave
small part of an area enclosed by another area, seen from the enclosing area
3.2.5
Face
two-dimensional element bounded by a closed sequence of Edges and by zero or more sets of
non-intersecting closed sequences of Edges within the first sequence of Edges
NOTE The Face is the atomic two-dimensional element.
3.2.6
graph
set of points and a set of arrows, with each arrow joining one point to another, whereby the points are called
Nodes of the graph, and the arrows are called the Edges of the graph
NOTE See Reference [34].
3.2.7
Intermediate Point
point, other than a Node, that defines the shape of an Edge
3.2.8
Line Feature
one-dimensional Feature defined as a sequence of one or more Edges
3.2.9
Node
zero-dimensional element that is a topological junction of two or more Edges, or an end point of an Edge
NOTE See Reference [34].
3.2.10
non-planar graph
graph which cannot be embedded in a plane
3.2.11
planar graph
graph which can be embedded in a plane, meaning that it can be drawn on the plane so that Edges intersect
only at a Node mutually incident with them
3.2.12
point
zero-dimensional element that specifies geometric location specified by one coordinate pair or triplet
NOTE See Reference [34].
3.2.13
Line Segment
Segment
direct connection between two Intermediate Points, two Nodes or a Node and an Intermediate Point
3.2.14
valency
degree
number of Edges which are incident with a particular Node
3.3 Geodetical terms
3.3.1
control point
point having known coordinates in the real world and identifiable with a corresponding point in a map or an
aerial photograph or satellite image
3.3.2
ellipsoidal height
distance between a point and the reference ellipsoid, measured along the ellipsoidal normal
3.3.3
geodetic datum
mathematical surface that approximates a portion of the earth's surface
3.3.4
geoid
model of the figure of the earth, that coincides with the mean sea level over the oceans and continues in
continental areas as an imaginary sea level surface, defined by spirit level
NOTE At every place, geoid level/surface is perpendicular to the pull of gravity. The shape is irregular but can, for
most purposes, be approximated by an oblate ellipsoid.
3.3.5
Geoid Undulation
difference between the orthometric height and the ellipsoidal height, measured along the ellipsoid normal
4 © ISO 2011 – All rights reserved

3.3.6
height
elevation
(vertical) distance between a point and the reference height level or the reference ellipsoid
NOTE On land maps, the reference level is commonly the mean sea level.
3.3.7
horizontal reference system
reference system for positions
3.3.8
magnetic declination
angle between Magnetic North and True North
NOTE See Reference [40].
3.3.9
map projection
transformation method used to represent the curved earth surface on a plane
3.3.10
offset
pair of values subtracted from all coordinate values in order to shorten these coordinate values
3.3.11
orthometric height
distance between a point and the geoid, measured along the perpendicular line
3.3.12
reference ellipsoid
oblate ellipsoid of revolution that is used to approximate the figure of the geoid
NOTE It is specified by two parameters: a semi-major axis a (equatorial radius of the earth) and a semi-minor axis b
(polar radius). The flattening f is defined as: f = (a − b)a.
3.3.13
reference height level
level to which all terrestrial heights are referred
NOTE It changes from country to country and it forms part of the national coordinate system for surveying and
mapping.
3.3.14
reference system
coordinate system on which a national survey is based
NOTE See Reference [40].
3.3.15
vertical reference system
reference system for elevations
3.3.16
world geodetic system
WGS
set of standard reference ellipsoids that define latitude, longitude and height for every point on the earth
3.4 GDF terms
NOTE All Feature Classes mentioned below are defined in the Feature Catalogue.
3.4.1
Album
collection of related Datasets (logical sub-division) and, if applicable, Volumes (physical sub-division)
3.4.2
Attribute
characteristic of a Feature which is independent of other Features
NOTE See Reference [34].
3.4.3
Attribute Code
alphanumeric identifier for an Attribute Type
NOTE See Reference [57].
3.4.4
Attribute Name
name associated to an Attribute Type
NOTE See Reference [57].
3.4.5
Attribute Type
defined characteristic of a Feature, which is independent of the other Features
3.4.6
Attribute Value
specific quality or quantity assigned to an Attribute
NOTE See Reference [34].
3.4.7
Dataset
sub-division of Album, which in turn can be sub-divided into Sections
NOTE A large set of data covering a particular geographic area can be considered a Dataset.
3.4.8
District
area regarded as a geographical unit, which is defined by the delivery of a specific public or private sector
service
3.4.9
Feature
database representation of a real world object
3.4.10
Feature Category
type of representation of a Feature, including Point, Line, Area and Complex Feature
3.4.11
Feature Class
categorization of a Feature
6 © ISO 2011 – All rights reserved

3.4.12
Feature Class Code
alphanumeric identifier for a Feature Class
NOTE See Reference [57].
3.4.13
Feature Name
name associated with a Feature Class
NOTE See Reference [34].
3.4.14
Feature Theme
specified group of related Features
3.4.15
field
set of characters representing one unit of data
3.4.16
Layer
certain subset of a Dataset based upon information contents
3.4.17
Manoeuvre
ordered sequence of a Road Element, a Junction and one or more Road Elements, and optionally associated
with a Traffic Sign
3.4.18
Place
administrative area of the types: Order-i Area, Country, Supra-National Area, Administrative Place A-Z or
Named Area Feature of the types: Built-up Area, Named Area, District
3.4.19
Property
combination of Attribute and Relationship values which pertain to a Feature and which together define a
certain characteristic of the Feature
3.4.20
Relationship Code
alphanumerical identifier for a Relationship
3.4.21
Relationship name
name associated with a Relationship Type
NOTE See Reference [34].
3.4.22
Relationship Type
defined characteristic of a Feature which is dependent on other Features
3.4.23
Semantic Relationship
Relationship
characteristic of a Feature involving other Features
3.4.24
Section
spatial subset of a Dataset
NOTE The coverage area of a map sheet, confined by geographic coordinates, can be considered a Section.
3.4.25
Transportation Element
Road Element, Pathway, Railway Element, Path, Ferry Connection, Water Body, Water Boundary Element,
Junction, Railway Element Junction or Water Boundary Junction
3.4.26
turn
ordered sequence of a Road Element, a Junction and a Road Element
NOTE A turn is a special case of a Manœuvre, relating exactly two Road Elements.
3.4.27
Volume
smallest physical unit of a medium
NOTE A single Volume can contain one or more GDF Datasets depending on Dataset size.
EXAMPLE A magnetic tape, a floppy disk, etc.

8 © ISO 2011 – All rights reserved

4 Symbolization and notation elements
4.1 GDF symbolizations
Many of the basic concepts of GDF are best expressed diagrammatically in data models. The Unified
Modeling Language (UML) [31] has been adopted as the conceptual modeling language for GDF.
4.2 UML notation
4.2.1 Introduction
This subclause provides a summary of the UML Class Diagram notation conventions used in this International
Standard. It is consistent with the use of UML in the ISO 191xx series of geographic information standards of
ISO/TC 211 (see [27], ISO 19107:2003, 5.1, Presentation and notation).
4.2.2 UML classes
4.2.2.1 General
A UML class is a description of a set of objects (instances) that share the same attributes, operations,
relationships , and semantics. A class is represented in a UML Class Diagram as in Figure 1.

Figure 1 — Class with attributes and operations
The rectangular box representing a class has three parts: class, attributes, and operations. The full class
content is usually only presented in one figure. If the class is repeated on another figure, attributes and
operations are not shown and the box is a single rectangle containing only the class name and stereotype as
in Figure 2:
Figure 2 — Class with attributes and operations suppressed
4.2.2.2 Class name and stereotype
The mandatory top part of the class rectangle contains the name of the class in UpperCamelCase. If the class
is abstract (it cannot have any instances), then the name is shown in italics.

GDF has its own definition of relationship. Here, the UML definition is used. It includes both associations and
generalizations between classes. Associations can be ordinary, aggregate, or composite.
Stereotype can take any of the following values:
Feature: (consistent with ISO 191xx) – classes that have identifiers can have geospatial location; primary
features in mapping; corresponds to GDF Feature classes.
Enumeration: (consistent with ISO 191xx) – class provides a fixed list of alternative values.
CodeList: (consistent with ISO 191xx) – similar to an enumeration, in that one of a number of values is
possible, but differs in intent, in that a code list may be expanded over time.
DataType: (consistent with ISO 191xx) – have no identity of their own; can be associated with other
classes but are not enumerations or code lists.
Union: (consistent with ISO 191xx) – a type consisting of one and only one of several alternatives (listed
as member attributes) representing a discriminating union of these alternatives.
Relationship: (special for GDF) – have identifiers; correspond to the Relationships between Features or
Attributes.
Attribute: (special for GDF) – correspond to GDF Composite Attributes.
Association: (special for GDF) – used to identify an Association Class (consistent with ISO 191xx) which
adds attributes to an association which exists between two classes.
4.2.2.3 UML class attributes
The middle part of the rectangular box representing a class optionally contains a set of attributes (properties)
for the class. Each attribute is specified by the following:
“attribute” is the name of an attribute of the class in lowerCamelCase. It is prefixed by a visibility indicator
with a value of public (+), private (-) or protected (#), indicating the visibility of this attribute from outside
the objects in this class. Most attributes in GDF have public visibility.
“[multiplicity]” indicates the number of values that this attribute can have for any instance of the class,
assumed to be organized as a set unless otherwise specified. M
...