SIST EN 28632-1:1997/A1:1997

Information technology - Computer graphics - Metafile for the storage and transfer of picture description information -

Informationstechnik - Graphische Datenverarbeitung - Datei für die Speicherung und Übertragung von Bildinformationen -

Technologies de l'information - Infographie - Métafichier de stockage et de transfert des informations de description d'

Information technology - Computer graphics - Metafile for the storage and transfer of picture description information - Part 1: Functional specification - Amendment 1: Rules for profiles (ISO/IEC 8632-1:1992, Amendment 1:1994)

General Information

• Status: Withdrawn
• Publication Date: 30-Nov-1997
• Withdrawal Date: 30-Sep-2003
• ICS: 35.140 - Computer graphics
• Technical Committee: ITC - Information technology
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 01-Oct-2003
• Due Date: 01-Oct-2003
• Completion Date: 01-Oct-2003
• Ref Project: EN 28632-1:1994/A1:1995 - Information technology - Computer graphics - Metafile for the storage and transfer of picture description information -

Relations

• Amends: SIST EN 28632-1:1997 - Information technology - Computer graphics - Metafile for the storage and transfer of picture description information -
• Effective Date: 22-Dec-2008

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 28632-1:1997/A1:1997
01-december-1997
Information technology - Computer graphics - Metafile for the storage and transfer
of picture description information - Part 1: Functional specification - Amendment
1: Rules for profiles (ISO/IEC 8632-1:1992, Amendment 1:1994)
Information technology - Computer graphics - Metafile for the storage and transfer of
picture description information -
Informationstechnik - Graphische Datenverarbeitung - Datei für die Speicherung und
Übertragung von Bildinformationen -
Technologies de l'information - Infographie - Métafichier de stockage et de transfert des
informations de description d'
Ta slovenski standard je istoveten z: EN 28632-1:1994/A1:1995
ICS:
35.140 5DþXQDOQLãNDJUDILND Computer graphics
SIST EN 28632-1:1997/A1:1997 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 28632-1:1997/A1:1997

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SIST EN 28632-1:1997/A1:1997

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SIST EN 28632-1:1997/A1:1997

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SIST EN 28632-1:1997/A1:1997
INTERNATIONAL ISO/IEC
STANDARD
8632-l
Second edition
1992-10-01
AMENDMENT 1
1994-12-15
Information technology - Computer graphics -
Metafile for the storage and transfer of picture
description information -
Part 1:
Functional specification
AMENDMENT ‘I: Rules for profiles
Technologies de /‘information - Infographie - Mbtafichier de stockage et de
transfeti des informations de description d’images -
Partie I: Description fonctionnelle
AMENDEMENT 7: R&g/es pour profils
Reference number
lSO/IEC 8632-1:1992/Amd.1:1994(E)

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SIST EN 28632-1:1997/A1:1997
ISO/IEC 8632-1: 1992/Amd.l: 1994(E)
Foreword
IS0 (the International Organization for Standardization) and IEC (the Inter-
national Electrotechnical Commission) form the specialized system for worldwide
standardization. National bodies that are members of IS0 or IEC participate in the
development of International Standards through technical committees established
by the respective organization to deal with particular fields of technical activity.
IS0 and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with
IS0 and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint
technical committee, ISO/IEC JTC 1. Draft International Standards adopted by the
joint technical committee are circulated to national bodies for voting. Publication
as an International Standard requires approval by at least 75 % of the national
bodies casting a vote.
Amendment 1 to International Standard ISO/IEC 8632-l: 1992 was prepared by
Joint Technical Committee ISO/IEC JTC 1, Information technology, Sub-
committee 24, Computer graphics and image processing.
o ISO/IEC 1994
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.
ISO/IEC Copyright Office l Case postale 56 l CI-I-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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SIST EN 28632-1:1997/A1:1997
ISOlIEC 863201:1992/Amd.1:1994 (E)
@ISO/IEC
Metafile for the storage and transfer
Information technology - Computer graphics -
of picture description information -
Part 1:
Functional specification
AMENDMENT 1: Rules for profiles
Page vii
Replace clause 7 in the Contents by:
...............................................
“7 Profiles and conformance
...................................................
7.1 Introduction
................................................
7.1.1 Objectives
...................................................
7.1.2Scope
............................
7.1.3 Concept and purpose of profiles for CGM
....................................
7.1.4 Purpose of the Model Profile
..................................................
7.2 Conformance
.......................................
7.2.1 Conformance of profiles
......................................
7.2.2 Conformance of metafiles
................................
7.2.3 Conformance of metafile generators
...............................
7.2.4 Conformance of metafile interpreters
7.3 Criteria for designing profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e e . . . .
................................
7.3.1 Criteria on the profile in its entirety
.........................
7.3.2 Criteria for the technical content of the profile
........................................
7.4Formandformatofaprofile
................................
7.5 Profile rules, proforma, and model profile
................................................
7.5.lOverview
...........................................
7.5.2 General principles
................................
7.5.2.1 Self-identification of profiles
..............................
7.5.2.2 Source identification of profiles
.......................................
7.5.2.3 Private encodings
.........................
7.5.2.4 Restrictions on grammar and state tables
7.5.2.5 Defining subsets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
........................................
7.5.2.6 Metafile defaults
.................................
7.5.2.7 Restricting element values
....................
7.5.2.8 Classification of elements and parameter values
...............................
7.5.2.9 Registered elements and values
...........................
7.5.2. IO Generator and interpreter behaviour
7.5.2.11 Physical media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.............................................
7.5.3 Multifile rules
..........................................
7.5.4 Multi-element rules
..............................................
7.5.4.1 Colour
....................................
7.5.4.2 Indexes (exceptcolour)
.........................
7.5.4.3 Line primitives - geometric degeneracies
........................
7.5.4.4 Area primitives - geometric degeneracies
.....................................
7.5.4.5 Graphical text strings
1

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SIST EN 28632-1:1997/A1:1997
@ISO/IEC
ISOIIEC 863201:1992/Amd. 1:1994 (E)
..................................
7.5.4.6 Non-graphical text strings
7.5.4.7 Data record strings .
.......................................
7.5.5 Individualelementrules
.............................
7.5.6 Generator implementation requirements
................................
7.5.6.1 Relationship to other profiles
.......................................
7.5.6.2 Generator fidelity
..................................
7.5.6.3 Preservation of primitives
.......................................
7.5.6.4 Semantic latitude
.................................
7.5.6.5 Generator error processing
............................................
7.5.6.6 Reporting
7.5.6.7 Degeneracies .
.............................
7.5.7 Interpreter implementation requirements
7.5.7.i Relationship to other profiles . . o e . . o 0 . 0 o ., . ., a o (d . o B a o B e Q e 0 0 B o e u
Numberofpictures .O~.~~U~~.O~.OCCUY~O~“~.~~~~~~~~*~.~~
7.5.7.2
o e e e e o e e e a D . o e . a e o o e a - * o D . o . o o e v a Q o B a . w o
7.5.7.3 Empty pictures
Interpreter fidelity . o . e s . . . . . e 0 ., o . . a o . c ., y . . o e o o . . e o . . o . d . e
7.5.7.4
7.5.7.5 Semantic latitude . . . o e o e . . e o o o . e m . Q o . . . . a e o . . . o c Q . e o e o . o
Interpreter error processing . e . . . . . . D . . . . e o o . . 0 . o e . . . . . . c . . . .
7.5.7.6
7.5.7.7 Reporting . . e e a e . . . . . . . . . e . . o . . o o . . . 0 . . . . . . o . . . . . e . e . e
7.5.7.8 Degeneracies . . . . . . . . . . o . e . . . . o e o . o * . . e D . . . . . . . o a c a o e . .
...............................................
7.5.8PPFtables.
...........................................
II Font character codes and metrics
II.1 Introduction .
..................................
He2 Association of character code to glyph
”
..............................................
Is.3 Font metric table
Puge 2
Clause 2: Add the following to the list of references.
“IS0 8601: 11988 Data elemems and in.terchange jbrmats - Information interchange - Representation of
dates and time.
- &bit sin,gle-byte coded graphic character sets - Latin alphabet
IS0 8859-l: 1987 lnformation,processin,g
No. 1.
Framework and taxonomy of International
ISO/IEC TR lOOOO- 1: 1992 Information technology -
Standardized Pro$les - Part 1: Framework.
Frllmework an.d taxonomy of International
ISO/IEC TR 10000-2: 1992 Information technology -
Standardized Profiles - Pl:rt 2: TNxon.omy of profiles. ”
Page 4
Clause 3.1: Add the following to the list of definitions:
“3.1.99 colour device: A device which offers more than two colours.

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SIST EN 28632-1:1997/A1:1997
@1s0/lEc ISO/IEC 8632.1:1992/Amd.1:1994 (E)
3.1.100 grey-scale device: A special case of colour device where hue and saturation are the same for all
colours (generally saturation = 0).
3.1.101 geometric degeneracy: The degeneracy is intrinsic to the parameterization of the element. A
degeneracy which results when parameterization for the geometry does not provide sufficient information
to draw the intended primitive.
y: The generator and the interpreter have the same understanding of the encodings,
the syntax, and the semantics of the metafile.
evice: A device which has only two colours, a foreground and a backgroun
colour”. The background colour is the colour of the display surface after it has been cleared.
PF): A template consisting of profile specifications, which is used by writers
A completed PPF specifies the rules and options of a
of profiles for generating instances of a profile.
profile of ISO/IEC 8632.”
Page 9
ause 3.2: Add the followhy to the list of abbreviation.
“ISP International Standardized Profile
PPF Profile Proforma”
Page 232
Replace Clause 7 with the fol1owin.g n.ew clause.
“7 Profiles and conformance
7.1 Introduction
7.1.1 Objectives
This clause provides rules for defining valid profiles of ISO/IEC 8632. Profiles are used as a method for
defining subsets of ISO/IEC 8632 by identifying the CGM elements, parameters, options, and
implementation requirements necessary for meeting a particular set of requirements.
The primary objectives of the profile rules are:
a) to promote interoperability by minimizing arbitrary subsets of ISO/IEC 8632;
b)
to provide the framework for developing profiles;
c) to promote uniformity in the development of conformance tests;

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SIST EN 28632-1:1997/A1:1997
ISO/lEC 8632.1:1992/Amd.1:1994 (E) @1s0/IEc
d) to supplement ISO/IEC TRlOOOO for International Standardized Profiles (ISPs) for the CGM
standard;
e) to provide a basis for evaluating profiles as potential ISPs.
7.1.2 Scope
This clause:
a) defines the concept of profiles of ISO/IEC 8632;
b) provides rules for defining profiles of ISO/IEC 8632;
c) provides conformance criteria for profiles of ISO/IEC 8632;
d) provides conformance criteria for metafiles, metafile generators, and metafile interpreters;
e) defines criteria on which to evaluate profiles of ISO/IEC 8632;
f’) provides a Profile Proforma (PPF) and Model Profile.
Implementation
This clause addresses the CGM data stream and implementation requirements.
requirements address the latitude allowed by CGM generators and interpreters. This clause does not
directly address the environmental, performance, or resource requirements of the generator or interpreter.
This clause does not define the application requirements or dictate application functional content of a
profile - the latter is the purview of application constituencies.
The scope of this clause is limited to rules for valid profiles for open interchange of graphical picture
metiles.
7.1.3 Concept and purpose of profiles for CGM
A major goal of ISO/IEC 8632 is to facilitate the transfer of picture information between computers, sites,
and applications.
Profiles provide a means to:
a) improve interoperability between implementations by inhibiting the proliferation of private
subsets of ISO/IEC 8632;
b) provide a foundation for testing and promote uniformity of conformance tests;
c) enhance the availability of consistent implementations of profiles.
A profile of ISO/IEC 8632 defines the options, elements, and parameters of ISO/IEC 8632 necessary to
accomplish a particular function and maximize the probability of interchange between systems
4

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SIST EN 28632-1:1997/A1:1997
@ISO/IEC ISOIIEC 8632~1:1992/Amd.1:1994 (E)
implementing the profile.
Profiles are defined by application constituencies who agree to adhere to the
same subset of CGM for the purpose of graphical data interchange using ISO/IEC 8632.
Alternatively,
profiles of ISO/IEC 8632 may be part of a set of interrelated standards and profiles assembled for the
purpose of accomplishing a larger functional purpose.
A profile may:
d) give the meaning of implementation dependent semantics of some elements;
e) enforce common resolution of ambiguous semantics of ISO/IEC 8632;
ensure that identical use of identical elements and parameter values has the same meaning;
0
g) specify subsets or groupings of registered items from the appropriate ISO/IEC registers;
h) prohibit undefined or ill-defined elements or parameter values.
A profile of ISO/IEC 8632, according to the taxonomy of ISO/IEC TRlOOOO-2, is an FCG Profile, that
is, an interchange format and representation profile of CGM.
A profile of ISO/IEC 8632 shall not specify any requirement that would contradict or cause non-
conformance to ISO/IEC 8632. Any metafile conforming to a profile of ISO/IEC 8632 conforms to
ISO/IEC 8632.
Profiles address metafile requirements, as well as implementation requirements for metafile generators and
metile interpreters. Profiles define maximum requirements for generators and minimum requirements
for interpreters.
7.1.4 Purpose of the Model Profile
The Model Profile serves two purposes:
1) It is a usable, implementable instance of a profile of ISO/IEC 8632. It is the only instance
contained in ISO/IEC 8632. While it is designed to be implementable on a range of systems,
it is also designed with modest limits that will not preclude its implementation in limited
The Model Profile may not be suitable
environments (low to mid-range computing systems).
for application communities with more advanced and demanding requirements.
2) It is a guide to writing profiles.
As an instance of a profile, the Model Profile is a starting point
from which an application-specific profile should be defined, for those application communities
for which the Model Profile itself does not suffice. Writers of profiles should consider each of
the specifications of the Model Profile and either accept the specifications where they are
adequate, or modify them when not.

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SIST EN 28632-1:1997/A1:1997
ISO/IEC 8632.1:1992/Amd.l:1994 (E)
@ISO/IEC
7.2 Conformance
7.2.1 Conformance of profiles
A profile of ISO/IEC 8632
a) shall meet all requirements specified in ISO/IEC 8632;
b) shall be structured in accordance with the structural components and presentation rules defined
in 7.4;
c) shall not specify any requirements that would contradict or cause non-conformance to ISO/IEC
8632;
d) may contain a conformance clause that adds requirements that are more specific and limited in
scope than ISO/IEC 8632;
e) shall meet the conformance requirements for a FCG Profile as defined in ISO/IEC TRlOOOO-1;
f) shall meet all the specific rules in this clause.
7.2.2 Conformance of metafiles
Conformance of rnetafiles to ISO/IEC 8632 is defined in terms of conformance to profi les. A metafi le
conforms to ISO/IEC 8632 if it conforms to a profile.
In order to conform to a profile of ISO/IEC 8632, a metafile
shall be a syntactically correct metafile for a specific version;
a)
b) shall conform to all profile requirements defined for that version.
A metafile is a syntactically correct version of ISO/IEC 8632 if the following conditions are met.
c) The metafile contains exactly one correct METAFILE VERSION element.
d) All graphical elements contained therein match the functional specification of the corresponding
elements of ISO/IEC 8632-l for that version. The metafile shall obey the relationships defined
in the formal grammar for that version, the state tables, and all other syntactic requirements for
that version.
e) The sequence of elements in the metafile obeys the relationships specified in ISO/IEC 8632-l
for that version, producing the structure specified in ISO/IEC 8632- 1. For example, the
metafile must begin with BEGIN METAFILE and end with END METAFILE, and include
exactly one metafile descriptor at the beginning which contains at least all the required elements.

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SIST EN 28632-1:1997/A1:1997
@1s0/rEc
ISO/IEC 8632~1:1992/Amd.1:1994 (E)
f) No elements appear in the metafile other than those specified in ISO/IEC 8632-l for that
version, unless required for the encoding technique. All non-standardized elements are encoded
using the ESCAPE or GDP elements or the external elements APPLICATION DATA and
MESSAGE.
g) The metafile is encoded according to the rules in one of the standardized encodings specified
in ISO/IEC 8632-2, ISO/IEC 8632-3, or ISO/IEC 8632-4.
7.2.3 Conformance of mebfile generators
Conformance of metafile generators is defined in terms of conformance to a particular profile of CGM.
is a profile of CGM which conforms to the rules of this clause, then a metafile generator is a
conforming p generator if it:
a) generates only metafiles which conform to the requirements of profile P or is directed to operate
in a mode where only such metafiles can be generated;
b) maps the graphical characteristics of the pictures onto a set of CGM elements which define those
pictures within the accuracy and latitude defined by the Generator Implementation Requirements
in the profile P.
.A metafile generator which conforms to the Model Profile for a specific version, shall:
c) generate no syntax in violation of that version of ISO/IEC 8632;
d) generate metafiles which conform to that version of the Model Profile;
e) map the graphical characteristics of application pictures onto a set of CGM elements which
define those pictures within the latitude allowed by the Generator Implementation Requirements
of the Model Profile.
7.2.4 Conformance of metafile int.erpreters
Conformance of metafile interpreters is defined in terms of conformance to a particular profile of CGM.
If P is a profile of CGM which conforms to the rules of this clause, then a metafile interpreter is a
conforming P interpreter if it:
a) is able to read any metafile which conforms to the requirements of profile P;
b) renders the graphical characteristics of the CGM elements in any such metafile into a graphical
image or picture within the accuracy and latitude defined by the Interpreter Implementation
Requirements in the profile P.
A metafile interpreter which conforms to the Model Profile for a specific version, shall:

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SIST EN 28632-1:1997/A1:1997
ISO/IEC 8632.1:1992/Amd.1:1994 (E) @1s0/IEc
C) be able to read any metafile which conforms to that version of the Model Profile of ISO/IEC
8632;
d) render the graphical characteristics of the CGM elements in any such metafile into a graphical
image or picture within the latitude defined by the Interpreter Implementation Requirements of
the Model Profile.
7.3 Criteria for designing profiles
The following criteria provide the means for determining the appropriateness and correctness of proposed
profiles. The objective is to limit the proliferation of profiles and ensure the quality of those profiles.
7.3.1 Criteria on the profile in its entirety
The following criteria shall be applied to a proposed profile.
a) The application constituency and functional purpose of a proposed profile shall be well defined.
b) The functional purpose of a proposed profile shall not be satisfied by an existing profile. If the
functional purpose of a proposed profile can be satisfied by a derivative of an existing profile,
it shall be so defined - significant subsets shall not be replicated.
c) The proposed profile shall meet the identified functional requirements.
7.3.2 Criteria for the technical cont.ent of the profile
The following criteria shall be applied to the technical content of a proposed profile.
a) A proposed profile shall not specify requirements that violate ISO/IEC 8632.
b) A proposed profile shall place requirements on the CGM and not on the internal behaviour,
structure, or performance of implementations (e.g., generators and interpreters).
c) A proposed profile may contain requirements on the functional and graphical characteristics of
implementations claiming conformance to the profile.
d) A proposed profile shall be consistent in its requirements regarding CGM elements and
parameters. For example, if a profile places no restrictions on the number of indexes defined
by the CHARACTER SET LIST element, then it is inconsistent to place a restriction on
CHARACTER SET INDEX.
e) A proposed profile shall not specify requirements which are conflicting, unnecessary, or
redundant.

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SIST EN 28632-1:1997/A1:1997
ISO/IEC 8632-1:1992/Amd.1:1994 (E)
@ISO/IEC
7.4 Form and format of a profile
A Profile of ISO/IEC 8632 shall contain the following components:
concise definition of the scope and purpose of the profile;
scenario illustrating the profile’s use and applicability;
c) all references to ISO/IEC 8632, i.e., approved amendments, errata, and registers.
d) references to any other relevant source documents;
e) specification of the set of elements, parameters, implementation requirements, and features of
ISO/IEC 8632, presented in the format and according to the rules of 7.5.
a definintion of conformance of metafiles and implementations to the profile.
0
The content and layout of the profile shall conform to the Rules for Drafting and Presentation of
Znternational Stcrn.clmdized ProJles in annex A of ISO/IEC TRlOOOO-1.
7.5 Profile rules, proforma, and model profile
7.5.1 Overview
This clause presents:
a) rules for defining CGM profiles;
b) a Profile Proforma (PPF);
c) a definition of the Model Profile.
Most of the profile rules are inherent
The PPF is a set of tables which are a template for writing profiles.
For example, the PPF requires certain information to be completed - each
in the structure of the PPF.
such case is a statement, equivalent to the rule, “Profiles shall specify . . . “.
All CGM profiles shall include a completed PPF.
This clause contains the completed PPF of the Model Profile.
The following subcluases address
- General Principles which apply to all profiles.
- Metafile Rules, which apply to the general characteristics of a conforming metafile.
- Multi-element Rules, which apply to several elements.

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SIST EN 28632-1:1997/A1:1997
ISOIIEC 8632-1:1992/Amd.1:1994 (E) @ISO/IEC
-
Individual Element Rules, which apply to the elements one by one. A rule is described for each
element defined in clause 5. Each rule in this subclause specifies whether a profile must address
the rule, whether a profile may optionally address the rule, or whether the profile shall not
restrict the use of the element in any manner.
- Generator Implementation Requirements, which apply to the behaviour of CGM generator
implementations.
- Interpreter Implementation Requirements, which apply to the behaviour of CGM interpreter
implementations.
Rules which address encoding issues are described in parts 2, 3, and 4 of ISO/IEC 8632.
The PPF is presented in tabular form supplemented by descriptive material.
The PPF template and the
Model Profile are presented together.
7.5.2 General principles
7.5.2.1 Self-identification of pro&s
It is required that the METAFILE DESCRIPTION element identify the profile, and its edition, to which
the metafiles conform. The edition indicates the version or release date of the profile.
7.5.2.2 Source identification of pro&s
The optional information of the PPF, for the METAFILE DESCRIPTION element, allows profiles to
require that metiles identify their source (e.g. 9 vendor, product, product version).
7.5.2.3 Private encodings
The “encodings” item of the PPF effectively prohibits profiles from specifying private encodings.
7.5.2.4 Restrictions on grammar and state tables
In completing the PPF, profile writers may restrict the use of some elements by restricting the formal
grammar or the state tables.
EXAMPLE - A profile may specify that segments are not allowed in Picture Body by either:
1) restricting the formal grammar:
Replace
:: = 1 < segment >
with
:: = .
10

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SIST EN 28632-1:1997/A1:1997
*1so/IEc
ISO/IJX 863201:1992/Amd.1:1994 (E)
2) modifying the state table:
Remove the ‘IX” in the POS column of table 8 in “BEGIN SEGMENT“.
3) making the statement:
Segments are not permitted to appear in the Picture Body.
7.5.2.5 Defining subsets
It is a principal role of profiles to define subsets of the options of ISO/IEC 8632. However, defining
subsets of ISO/IEC 8632 shall not be arbitrary and shall have a clear connection to the achievement of one
or more of the defined goals of the profile.
7.5.2.6 Metafile defaults
Clause 6 addresses all elements which have default values. While no profile can change these values, an
equivalent effect may be achieved by use of the METAFILE DEFAULn REPLACEMENT element.
Profiles may require that a metafile contain a METAFILE DEFAULn REPLACEMENT element with
well-defined con tent .
For default values in clause 6 which are listed as “device dependent” or “interpreter dependent”, if there
is a element for setting the value of such an element, then profiles shall require the use of such elements.
The appropriate element shall be included in the METAFILE DEFAULT REPLACEMENT element or
in the metafile body. For such elements, profiles shall not assign implicit defaults. These elements
include:
For profiles of Version 2 (and above)
LINE REPRESENTATION
MARKER REPRESENTATION
TEXT REPRESENTATION
FILL REPRESENTATION
EDGE REPRESENTATION
Specifying the default value for elements which specify colour values shall be consistent with the rules for
colour (see 7.5.4.1). Specifically, if all colours used within the metafile shall be defined, then the element
for setting the colour value shall be used; otherwise, the element shall not be used. The elements affected
by this rule are:
When specified as a direct colour:
BACKGROUND COLOUR
COLOUR TABLE LINE COLOUR
MARKER COLOUR
TEXT COLOUR
FILL COLOUR
EDGE COLOUR
11

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SIST EN 28632-1:1997/A1:1997
ISODEC 86324:1992/Amd. I:1994 (E) @1s0/IEc
If no element exists to set the value, then the profile shall define the default values to be used. The
elements affected by this rule, because they do not exist in Version 1 include:
For profiles of Version 1 (only)
LINE REPRESENTATION
MARKER REPRESENTATION
TEXT REPRESENTATION
FILL REPRESENTATION
EDGE REPRESENTATION
7.5.2.7 Restricting element. values
In those cases where it is necessary to restrict an element to its default value in order to meet the goa s of
a profile, the restriction shall be achieved by allowing the element to appear in conforming files and
restricting its value to the default rather than prohibiting the element.
NOTE -The implementation burden necessary to implement this guideline is small compared to the interoperal ility
gain. Many implementations, even if only interested in the default value, consider such a “defensive“ strategy to
be good insurance against mistakes of other implementations in realizing the defaults of ISO/IEC 8632.
7.5.2.8 Classification of elements and parameter values
Elements and parameter values can be classified as either standard, registered, profile-defined, or private.
- Standard refers to elements and parameter values which have been defined in ISO/IEC 8632.
- Registered refers to elements and parameter values which have been entered into a registry and
thus, have an internationally recognized definition and have undergone a standardization
process.
- Profile-defined refers to elements such as ESCAPES and GDPs, whose syntax, semantics, and
identifier are defined within the profile.
- Private refers to truly private elements and parameter values, that is, known only by prior
agreement between generators and interpreters.
Profiles shall limit metafiles to standard, registered, and profile-define
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