1、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 jour
2、INTERNATIONAL 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,o
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11、e(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 fe
12、edback 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:Colo
13、r 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 numberOfCo
14、ntours 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
15、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-fi
16、ll 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
