ISO/TR 14825:1996

TECHNICAL ISOTTR
REPORT 14825
First edition
1996-11-15
Geographic Data Files (GDF)
Fichiers de don&es ggographiques
Reference number
ISOTTR 14825: 1996(E)
ISOmR 14825:1996(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). The work of
preparing International Standards is normally carried out through IS0
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-
in liaison with ISO, also take part in the work. IS0
governmental,
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
The main task of technical committees is to prepare International
Standards. In exceptional circumstances a technical committee may
propose the publication of a Technical Report of one of the following types:
the required S upport cannot
- type 1, when be obtai ned for the
publication of an Internationa IS tandard, despite eated efforts;
rep
- type 2, when the subject is still under technical development or where
for any other reason there is the future but not immediate possibility of
an agreement on an International Standard;
- type 3, when a technical committee has collected data of a different
kind from that which is normally published as an International
Standard (“state of the art”, for example).
Technical Reports of types 1 and 2 are subject to review within three years
of publication, to decide whether they can be transformed into International
Standards. Technical Reports of type 3 do not necessarily have to be
reviewed until the data they provide are considered to be no longer valid or
useful.
ISOTTR 14825, which is a Technical Report of type 2, was prepared by the
European Committee for Standardization (CEN) in collaboration with IS0
Technical Committee ISOmC 204, Transport information and control
systems, in accordance with the Agreement on technical cooperation
between IS0 and CEN (Vienna Agreement).
This document is being issued in the Technical Report (type 2) series of
publications (according to subclause G.3.2.2 of part 1 of the ISO/IEC
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 l CH-1211 Geneve 20 l Switzerland
Internet central @ isocs.iso.ch
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Printed in Switzerland
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lSO/TR 14825: 1996(E)
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Directives, 1995) as a “prospective standard for provisional application” in
the field of transport information and control systems because there is an
urgent need for guidance on how standards in this field should be used to
meet an identified need.
This document is not to be regarded as an “International Standard”. It is
proposed for provisional application so that information and experience of
its use in practice may be gathered. Comments on the content of this
document should be sent to the lSO/TC 204 Secretariat.
A review of this Technical Report (type 2) will be carried out not later than
three years after its publication with the options of: extension for another
three years; conversion into an International Standard; or withdrawal.

ISO/TR 14825: 1996(E)
INTRODUCTION
The Geographic Data Files (GDF) standard has been developed to meet the needs of professionals and
organizations involved in the creation, update, supply and application of referenced and structured road network
data.
It has been created in order to improve the efficiency of the capture, the production and handling of road related
geographic information. This increase in efficiency is obtained by supplying a common reference model on which
users can base their requirements and producers can base their product definition. In addition to this, the standard
facilitates the exchange of information, defined according to this reference model. For this it contains the definition
of an exchange format which avoid compatibility problems at both the users and the producersS side of the
information flow. In this respect, producers and users should not be viewed as two totally distinct groups- It is
envisaged that an important application of the standard will be the combination of information present in already
existing geographic information data bases into one, more comprehensive source of road-related information”
To ensure maximum compatibility with these already existing sources and also to make use of the strengths of the
structure in which these sources have been defined, the basic foundation of the standard is based on a general,
non-application specific data model. On top of this data model, a road network specific application model has been
built. Together they make up the GDF standard. Due to its general character, the data model also is able to support
other types of applications, thus facilitating the future creation of a wide variety of geographic information sources
which can be combined with maximum flexibility.
The standard consists of twelve chapters, of which six (chapter 5 to 10) together form the reference model. They
each contain the elaboration and definition of one clearly identifiable aspect of road related information. Chapter 4
contains a more general description of the standard. It contains the definition of the general data model as well as
the definition of the basic components of the standard, thus explaining the structure of the rest of the standard.
Chapter 11 describes the logical data structure by which the conceptual models as defined in the previous chapters
can be represented.
Chapter 12 defines the exchange format by which the information can be exchanged.

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ISO/TR 14825: 1996(E)
I. SCOPE
This standard specifies a system for the interchange of digital road related geographic information. It
takes into account all the requirements of applications in the road transport and traffic telematics
(RTTT) field. Within this field, the standard is application independent. The standard contains the
following detailed specifications :
a) A reference model according to which the information covered by the standard shall be defined.
The core of the reference model is formed by a data model and a data dictionary in which the
individual information components and their interrelations are defined.
A specification of ways of representation of the information components contained.
) The specification how to define meta information. An important aspect is the quality of the
information defined according to the standard. This aspect is dealt with separately in the sense that
the methodology is defined with which the quality of the information components contained can be
measured.
A specification for an exchange format reflecting the reference model.

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ISO/TR 148253 996(E)
2 R REFERENCES
21 . Normative References
Working Party to Produce National Standards for the Transfer of Digital Map Data; National
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Transfer Format, Release 1 .I ; Ordnance Survey; Southampton, U.K.; January 1989
National Committee for Digital Cartographic Data Standards et al.; Spatial Data Transfer Standard;
U.S. Geological Survey, National Mapping Division; Columbus, Ohio, USA; June 1990
International Federation of Library Associations and Institutions, Joint Working Group on the
International Standard Bibliographic Description for Cartographic Materials; ISBD(CM):
International Standard Bibliographic Description for Cartographic Materials; IFLA International
Office for UBC; London, U.K.; 1977
Bibliographic Systems Office, Working Group on Bibliographic Codes; Revised List of Languages
and Language Codes; Library of Congress, Bibliographic SystemsOffice; Washington D.C., U.S.A;
ISO; International Standard IS0 690, Documentation -Bibliographic references - Content, form and
structure; International Organisation for Standardisation; 1987
ISO; International Standard IS0 6709, Standard representation of latitude, longitude and altitude
for geographic point locations; International Organisation for Standardisation; 1983
ISO; International Standard IS0 3166; Codes for the representation of names of countries.;
International Organisation for Standardisation; 1993
ISO; International Standard IS0 2108, Information and documentation - International Standard
Book Numbering (ISBN); International Organisation for Standardisation; 1992
ISO; International Standard IS0 3297; Documentation - International Standard Serial Numbering
(ISSN); International Organisation for Standardisation; 1986
lSO/IEC; International Standard 8859-I) Information processing - 8-bit single-byte coded graphic
character sets - Part 1: Latin alphabet No. 1; International Organisation for Standardisation; 1987
ISO; International Standard 2859, Sampling procedures for inspection by attributes; International
Organisation for Standardization; 1985-l 995 (all parts)
AFNOR; Norme expkrimentale: Echanges de donneirs informatisees dans le domaine de
I’lnformation Geographique - EDlG&O; Association Franc;aise de Normalisation;Paris, 1991;
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ISO/TR 14825: 1996(E)
2.2 Digital Geographic Information Working Group; Digital Geographic
Information Exchange Standard (DIGEST); December 1989; Other references
131 FIG; Technical Dictionary, terms and definitions as used in surveying and mappingin Germany;
lnstitute for Applied Geodesy; Frankfurt am Main; 1971
141 ICA; Multilingual Dictionary of Technical Terms in Cartography; InternationalCartographic
Association; Wiesbaden; 1973
151 DTV; DTV-Lexikon; Deutscher Taschenbuchen-Verlag; 1975
161 The Shorter Oxford English Dictionary
171 Claude Berge; Graphs; North-Holland Mathematical Library, Volume 6 - Part 1; North Holland;
Amsterdam, New York, Oxford; 1985
181 Mehdi Behzad, Gary Chartrand; Introduction to the Theory of Graphs; Allyn and Bacon Inc.;
Boston, Massachusetts; 1971
191 Nijssen G.M, Halpin T.A.; Conceptual Schema and Relational Database Design - A fact oriented
approach; Prentice Hall, Sydney; 1989

ISO/TR 14825: 1996(E)
3. DEFINITIONS
The numbers between square brackets refer to the reference documents mentioned in 2.
3.1 General terms
3.3 .I Accuracy
The closeness of results of observations, computations or estimates to the true values or the values as
accepted as being true [2]
3.1.2 Cartography
The art, science and technology of making maps, together with their study as scientific documents and
works of art[l5]
3.1.3 Cartographic Primitive
Atomic construction element in a cartographic representation, i.e. Node, Edge and Face.
3.1.4 Data Fiie
A collection of related data records.[2] The records shall have a homogeneous structure.
3.1.5 Data Retard
A record containing feature related data
3.1 x6 Data set
A large set of data covering a particular geographic area
3.1.7 Entity
A real world phenomenon that is not subdivided into phenomena of the same kind (e.g. a bridge) [2]
3.1.8 Error Rate
The percentage of falsehoods
3.1.9 Field
A specified part of a record containing a unit of data. The unit of data may be a data element or a data
item [I]
3.1 .I0 Geudesy
Science of determination of the shape and gravity field of the earth and of survey and mapping of the
physical surface of the earth [14]
3.1 .I 1 Geography
Science of phenomena of the earth’s surface, its being and growing and its manifold relations [16]
3.1 .I 2 Geumetry
Science of the characteristics of spatial figures [16]
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3.1 .I3 Global Record
A record that logically precedes the data records and contains control parameters, data definition and
documentation necessary to interpret companion data records [ISO 821 I]
3.1 .+I4 information Unit
A collection of information that may be regarded as an undivided whole, e.g. 1 data set, I section, 1
layer
3.1 .I5 Logical Dumain
The range of attribute values to which a meaning has been assigned.
3.1 .I6 Logical Unit
A collection of data that may be regarded as a logically undivided whole, e.g. 1 logical record.
3.1.17 Medium Unit
An object for data storage that can be considered as a physically undivided whole, e.g. 1 floppy disk, 1
magnetic tape etc.
3.1 .I8 Physical Unit
A unit of data storage that may be regarded as physically undividable.
3.1 .I 9 Precision
The closeness of measurements of the same phenomenon repeated under exactly the same
conditions and using the same techniques.
3.1.20 Primitive
Fundamental form from which all other forms can be derived [17]
3.121 Repeating Attribute Type
An attribute type that may have multiple values associated to one and the same instance of a particular
feature type.
3.1.22 Resolution
The smallest unit which can be detected. It fixes a limit to precision and accuracy.
3.1.23 Spatial Domain
The description of the limits of a geographical area to which a particular set of data spatially belongs to.
3.124 Source Material
The origin of data in analogue or digital representation, stored on any kind of data medium.
3.1.25 Topography
The technical and conceptual registration of the terrain, its features and properties of the landscape
.
WI
3.1.26 Topology
The field of mathematics that deals with characteristics of geometric structures that keep preserved
after continual variation [ 161

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ilSO/rR 14825:1996(E)
3.1.27 Transcription
Render ,ing of geographic na ,mes from a non-alphabetic script into an alphabetic one or vice versa. The
term is also applied to initial reco rding script of hitherto unwritten names [15]
3.1.28 Up-to-dateness
The closeness in time of the (geographic) data to the present reality.

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lSO/TR 14825: 1996(E)
3.2 Mathematical terms
3.2.1 Area Feature
A two dimensional feature. An area feature is defined by one or more faces.’
3.2.2 Edge
A directed sequence of non-intersecting line segments with nodes at each end [2]
3.2.3 Encfave
Small part of an area enclosed by another area
...