ISO_IEC_14496-22_2019_Amd_1_2020.pdf

Information technology Coding of audio-visual objects Part 22:Open Font FormatAMENDMENT 1:Color font technology and other updatesTechnologies de linformation Codage des objets audiovisuels Partie 22:Format de police de caractres ouvertAMENDEMENT 1:Technologie des polices colores et autres mises jourINTERNATIONAL STANDARDISO/IEC14496-22Fourth edition2019-01Reference numberISO/IEC 14496-22:2019/Amd.1:2020(E)AMENDMENT 12020-06 ISO/IEC 2020 ISO/IEC 14496-22:2019/Amd.1:2020(E)ii ISO/IEC 2020 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO/IEC 2020All rights reserved.Unless otherwise specified,or required in the context of its implementation,no part of this publication may be reproduced or utilized otherwise in any form or by any means,electronic or mechanical,including photocopying,or posting on the internet or an intranet,without prior written permission.Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCP 401 Ch.de Blandonnet 8CH-1214 Vernier,GenevaPhone:+41 22 749 01 11Email:copyrightiso.orgWebsite:www.iso.orgPublished in Switzerland ISO/IEC 14496-22:2019/Amd.1:2020(E)ForewordISO(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 IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity.ISO and IEC technical committees collaborate in fields of mutual interest.Other international organizations,governmental and non-governmental,in liaison with ISO and IEC,also take part in the work.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives,Part 1.In particular,the different approval criteria needed for the different types of document should be noted.This document was drafted in accordance with the editorial rules of the ISO/IEC Directives,Part 2(see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.ISO and IEC shall not be held responsible for identifying any or all such patent rights.Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received(see www.iso.org/patents)or the IEC list of patent declarations received(see http:/patents.iec.ch).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation of the voluntary nature of standards,the meaning of ISO specific terms and expressions related to conformity assessment,as well as information about ISOs adherence to the World Trade Organization(WTO)principles in the Technical Barriers to Trade(TBT)see www.iso.org/iso/foreword.html.This document was prepared by Joint Technical Committee ISO/IEC JTC 1,Information technology,Subcommittee SC 29,Coding of audio,picture,multimedia and hypermedia information.A list of all parts in the ISO/IEC 14496 series can be found on the ISO website.Any feedback or questions on this document should be directed to the users national standards body.A complete listing of these bodies can be found at www.iso.org/members.html.ISO/IEC 2020 All rights reserved iii Information technology Coding of audio-visual objects Part 22:Open Font FormatAMENDMENT 1:Color font technology and other updates 4.5.2Replace the description of the“Offset”field in the“Table Directory”table with the following:Offset from beginning of OFF font file.5.3.4.1.1Replace the first sentence of the first paragraph with the following:This is the table information needed if numberOfContours is greater than or equal to zero,that is,a glyph is not a composite.Replace the final paragraph(immediately following the“Simple Glyph flags”table)with the following:A non-zero-fill algorithm is needed to avoid dropouts when contours overlap.The OVERLAP_SIMPLE flag is used by some rasterizer implementations to ensure that a non-zero-fill algorithm is used rather than an even-odd-fill algorithm.Implementations that always use a non-zero-fill algorithm will ignore this flag.Note that some implementations might check this flag specifically in non-variable fonts,but always use a non-zero-fill algorithm for variable fonts.This flag can be used in order to provide broad interoperability of fonts particularly non-variable fonts when glyphs have overlapping contours.Note that variable fonts often make use of overlapping contours.This has implications for tools that generate static-font data for a specific instance of a variable font,if broad interoperability of the derived font is desired:if a glyph has overlapping contours in the given instance,then the tool should either set this fl