1、National Standard of CanadaCAN/CSA-ISO/IEC 8632-3-01(ISO/IEC 8632-3:1999)International Standard ISO/IEC 8632-3:1999 (second edition, 1999-12-15), has been adopted withoutmodification as CSA Standard CAN/CSA-ISO/IEC 8632-3-01, which has been approved as a NationalStandard of Canada by the Standards C
2、ouncil of Canada.ISBN 1-55324-422-2 March 2001Reference numberISO/IEC 18632-3:1999(E) ISO/IEC1999The Canadian Standards Association, which The Standards Council of Canada is theoperates under the name CSA International coordinating body of the National Standards system, (CSA), under whose auspices t
3、his National Standard has a federation of independent, autonomousbeen produced, was chartered in 1919 and accredited by organizations working towards the furtherthe Standards Council of Canada to the National development and improvement of voluntaryStandards system in 1973. It is a not-for-profit, s
4、tandardization in the national interest.nonstatutory, voluntary membership association The principal objects of the Council are to foster engaged in standards development and certification and promote voluntary standardization as a means activities. of advancing the national economy, benefiting theC
5、SA standards reflect a national consensus of producers health, safety, and welfare of the public, assisting and users including manufacturers, consumers, and protecting the consumer, facilitating domestic retailers, unions and professional organizations, and and international trade, and furthering i
6、nternationalgovernmental agencies. The standards are used widely cooperation in the field of standards.by industry and commerce and often adopted by A National Standard of Canada is a standard whichmunicipal, provincial, and federal governments in their has been approved by the Standards Council ofr
7、egulations, particularly in the fields of health, safety, Canada and one which reflects a reasonablebuilding and construction, and the environment. agreement among the views of a number of capableIndividuals, companies, and associations across Canada individuals whose collective interests provide to
8、 theindicate their support for CSAs standards development greatest practicable extent a balance ofby volunteering their time and skills to CSA Committee representation of producers, users, consumers, andwork and supporting the Associations objectives others with relevant interests, as may be appropr
9、iatethrough sustaining memberships. The more than 7000 to the subject in hand. It normally is a standardcommittee volunteers and the 2000 sustaining which is capable of making a significant and timelymemberships together form CSAs total membership contribution to the national interest.from which its
10、 Directors are chosen. Sustaining Approval of a standard as a National Standard ofmemberships represent a major source of income for Canada indicates that a standard conforms to theCSAs standards development activities. criteria and procedures established by the StandardsThe Association offers certi
11、fication and testing services Council of Canada. Approval does not refer to thein support of and as an extension to its standards technical content of the standard; this remains thedevelopment activities. To ensure the integrity of its continuing responsibility of the accreditedcertification process
12、, the Association regularly and standards-development organization.continually audits and inspects products that bear the Those who have a need to apply standards areCSA Mark. encouraged to use National Standards of CanadaIn addition to its head office and laboratory complex in whenever practicable.
13、 These standards are subject Toronto, CSA has regional branch offices in major centres to periodic review; therefore, users are cautioned across Canada and inspection and testing agencies in to obtain the latest edition from the organizationeight countries. Since 1919, the Association has preparing
14、the standard.developed the necessary expertise to meet its corporate The responsibility for approving National Standards mission: CSA is an independent service organization of Canada rests with thewhose mission is to provide an open and effective forum Standards Council of Canadafor activities facil
15、itating the exchange of goods and 270 Albert Street, Suite 200services through the use of standards, certification and Ottawa, Ontario, K1P 6N7related services to meet national and international needs. CanadaFor further information on CSA services, write toCSA International178 Rexdale BoulevardToron
16、to, Ontario, M9W 1R3CanadaAlthough the intended primary application of this Standard is stated in its Scope, it is importantto note that it remains the responsibility of the users to judge its suitability for their particular purpose.Registered trade-mark of Canadian Standards AssociationInformation
17、 technology Computer graphics Metafile for the storage andCAN/CSA-ISO/IEC 8632-3-01 transfer of picture description information Part 3: Binary encodingMarch 2001 CSA/1CAN/CSA-ISO/IEC 8632-3-01Information technology Computergraphics Metafile for the storageand transfer of picture descriptioninformati
18、on Part 3: BinaryencodingCSA PrefaceStandards development within the Information Technology sector is harmonized with internationalstandards development. Through the CSA Technical Committee on Information Technology (TCIT),Canadians serve as the Canadian Advisory Committee (CAC) on ISO/IEC Joint Tec
19、hnical Committee 1 onInformation Technology (ISO/IEC JTC1) for the Standards Council of Canada (SCC), the ISO memberbody for Canada and sponsor of the Canadian National Committee of the IEC. Also, as a member of theInternational Telecommunication Union (ITU), Canada participates in the International
20、 Telegraph andTelephone Consultative Committee (ITU-T).This International Standard was reviewed by the CSA TCIT under the jurisdiction of the StrategicSteering Committee on Information Technology and deemed acceptable for use in Canada. (Acommittee membership list is available on request from the CS
21、A Project Manager.) From time to time,ISO/IEC may publish addenda, corrigenda, etc. The CSA TCIT will review these documents for approvaland publication. For a listing, refer to the CSA Information Products catalogue or CSA Info Update orcontact a CSA Sales representative. This Standard has been for
22、mally approved, without modification, bythese Committees and has been approved as a National Standard of Canada by the Standards Council ofCanada.March 2001 CSA International 2001All rights reserved. No part of this publication may be reproduced in any form whatsoever without the prior permission of
23、the publisher. ISO/IEC material is reprinted with permission. Inquiries regarding this National Standard of Canada shouldbe addressed to CSA International, 178 Rexdale Boulevard, Toronto, Ontario, M9W 1R3.Reference numberISO/IEC 8632-3:1999(E)ISO/IEC 1999INTERNATIONALSTANDARDISO/IEC8632-3Second edit
24、ion1999-12-15Information technology Computergraphics Metafile for the storage andtransfer of picture descriptioninformation Part 3:Binary encodingTechnologies de linformation Infographie Mtafichier de stockageet de transfert des informations de description dimages Partie 3: Codage binaireISO/IEC 863
25、2-3:1999(E)PDF disclaimerThis PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall notbe edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading th
26、isfile, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in thisarea.Adobe is a trademark of Adobe Systems Incorporated.Details of the software products used to create this PDF file can be found in the General Info
27、relative to the file; the PDF-creation parameterswere optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely eventthat a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO
28、/IEC 1999All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronicor mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member bodyin the
29、 country of the requester.ISO copyright officeCase postale 56 Gb7 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 734 10 79E-mail copyrightiso.chWeb www.iso.chii ISO/IEC 1999 All rights reservedISO/IEC 8632-3:1999(E) ISO/IEC 1999 All rights reservediiiContents Page1 Scope12 Conformance.13 Normati
30、ve references .24 Notational conventions 25 Overall structure .25.1 General form of metafile.25.2 General form of pictures 25.3 General structure of the binary metafile.35.4 Structure of the command header 46 Primitive data forms66.1 Signed integer.66.1.1 Signed integer at 8-bit precision.66.1.2 Sig
31、ned integer at 16-bit precision.66.1.3 Signed integer at 24-bit precision.76.1.4 Signed integer at 32-bit precision.76.2 Unsigned integer.76.2.1 Unsigned integers at 8-bit precision.76.2.2 Unsigned integers at 16-bit precision.76.2.3 Unsigned integers at 24-bit precision.76.2.4 Unsigned integers at
32、32-bit precision.86.3 Character86.4 Fixed point real86.4.1 Fixed point real at 32-bit precision86.4.2 Fixed point real at 64-bit precision86.4.3 Value of fixed point reals86.5 Floating point 96.5.1 Floating point real at 32-bit precision.9ISO/IEC 8632-3:1999(E)iv ISO/IEC 1999 All rights reserved6.5.
33、2 Floating point real at 64-bit precision.107 Representation of abstract parameter types108 Representation of each element158.1 Method of presentation 158.2 Delimiter elements 168.3 Metafile descriptor elements188.4 Picture descriptor elements.258.5 Control elements.308.6 Graphical primitive element
34、s.338.7 Attribute elements.418.8 Escape element.508.9 External elements518.10 Segment control and segment attribute elements 528.11 Application structure descriptor elements.569 Defaults5710 Profile encoding rules, proforma, and Model Profile 5710.1 Encodings5710.2 Metafile defaults5710.3 Floating p
35、oint values5710.4 Profile proforma tables (PPF) 5710.5 Permissible alternative coding representation58Annex A (normative) Formal grammar59Annex B (informative) Examples61Annex C (informative) List of binary encoding metafile element codes64ISO/IEC 8632-3:1999(E) ISO/IEC 1999 All rights reservedvFore
36、wordISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)form the specialized system for worldwide standardization. National bodies that are members of ISO or IECparticipate in the development of International Standards through technical com
37、mittees established by therespective organization to deal with particular fields of technical activity. ISO and IEC technical committeescollaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, inliaison with ISO and IEC, also take part in the wo
38、rk.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.Draft International Standards adopted by the joint technical committee are circu
39、lated to national bodies for voting.Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote.Attention is drawn to the possibility that some of the elements of this part of ISO/IEC 8632 may be the subject ofpatent rights. ISO and IEC shall not
40、 be held responsible for identifying any or all such patent rights.International Standard ISO/IEC 8632-3 was prepared by Joint Technical Committee ISO/IEC JTC 1, Informationtechnology, Subcommittee SC 24, Computer graphics and image processing.This second edition cancels and replaces the first editi
41、on (ISO/IEC 8632-3:1992), which has been technicallyrevised. It also incorporates Amendment 1:1994 and Amendment 2:1995. Note that the previous edition ofISO/IEC 8632-3, published in 1992, was a first edition but second edition was indicated by error on its cover pageand in the foreword.ISO/IEC 8632
42、 consists of the following parts, under the general title Information technology Computer graphics Metafile for the storage and transfer of picture description information: Part 1: Functional specification Part 3: Binary encoding Part 4: Clear text encodingAnnex A forms a normative part of this part
43、 of ISO/IEC 8632. Annexes B and C are for information only.NOTE In previous editions of ISO/IEC 8632, Part 2 defined a Character Encoding. Part 2 was withdrawn in 1998, due to its lackof implementation and use.ISO/IEC 8632-3:1999(E)vi ISO/IEC 1999 All rights reservedIntroduction0.1 Purpose of the Bi
44、nary EncodingThe Binary Encoding of the Computer Graphics Metafile (CGM) provides a representation of the Metafile syntaxthat can be optimized for speed of generation and interpretation, while still providing a standard means ofinterchange among computer systems. The encoding uses binary data format
45、s that are much more similar to thedata representations used within computer systems than the data formats of the other encodings.Some of the data formats may exactly match those of some computer systems. In such cases processing isreduced very much relative to the other standardized encodings.On mo
46、st computer systems processing requirements for the Binary Encoding will be substantially lower thananother encoding.In cases where a computer systems architecture does not match the standard formats used in the BinaryEncoding, and where absolute minimization of processing requirements is critical,
47、and where interchange amongdissimilar systems does not matter, it may be more appropriate to use a private encoding, conforming to the rulesspecified in clause 7 of ISO/IEC 8632-1.0.2 ObjectivesThis encoding has the following features.a) Partitioning of parameter lists: metafile elements are coded i
48、n the Binary Encoding by one or morepartitions (see clause 5); the first (or only) partition of an element contains the opcode (Element Class plusElement Id).b) Alignment of elements: every element begins on a word boundary. When the data of an element (whetherpartitioned or not) does not terminate
49、on an even-octet boundary, then the following element is aligned bypadding after the data of the preceding element with zero bits to the next even-octet boundary. A no-opelement is available in this encoding. It is skipped and ignored by interpreters. It may be used to aligndata on machine-dependent record boundaries for speed of processing.c) Uniformity of format: all elements have an associated parameter length value. The length is specified asan octet count. As a result, it is possible to scan the metafile, without interp
