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PDF 1.7 Specification - Front Matter

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First Edition 2008-7-1

Document management - Portable document format - Part 1: PDF 1.7

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Copyright Notice

This document has been derived directly from the copyright ISO 32000-1 standard document available for purchase from the ISO web site at http://www.iso.org/iso/iso\_catalogue/catalogue\_tc/catalogue\_detail.htm?csnumber=51502. It is being made available from the web site of Adobe Systems Incorporated (http://www.adobe.com/devnet/pdf/ pdf_reference.html) under agreement with ISO for those that do not need the official version containing the ISO logo and copyright notices. This version of the ISO 32000-1 standard is copyright by Adobe Systems Incorporated through an agreement with ISO who is the copyright owner of the official ISO 32000-1 document of which this is an authorized copy.\

The technical material is identical between this version and the ISO Standard; the page and sections numbers are also preserved. Requests for permission to reproduce this document for any purpose should be arranged with ISO.

Contents

Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.2 Conforming readers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.3 Conforming writers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.4 Conforming products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3 Normative references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
4 Terms and definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5 Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 Version Designations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
7 Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
7.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
7.2 Lexical Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
7.3 Objects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
7.4 Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
7.5 . . File Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
7.6 Encryption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
7.7 Document Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
7.8 Content Streams and Resources . . . . . . . . . . . . . . . . . . . 81
7.9 Common Data Structures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
7.10 Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
7.11 File Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
7.12 Extensions Dictionary . . . . . . . . . . . . . . . . . . . . . . . . . . 108
8 Graphics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
8.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
8.2 Graphics Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
8.3 Coordinate Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.4 Graphics State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
8.5 Path Construction and Painting . . . . . . . . . . . . . . . . . . . 131
8.6 Colour Spaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
8.7 Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
8.8 External Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
8.9 Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
8.10 Form XObjects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
8.11 Optional Content. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
9 Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
9.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
9.2 Organization and Use of Fonts . . . . . 237
9.3 . . . . . . . . . . . . . . . Text State Parameters and Operators. . . . . . . . . . . . . . . 243
9.4 Text Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
9.5 Introduction to Font Data Structures . . . . . . . . . . . . . . . 253
9.6 Simple Fonts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
9.7 Composite Fonts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
9.8 Font Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
9.9 Embedded Font Programs. . . . . . . . . . . . . . . . . . . . . . . . 288
9.10 Extraction of Text Content. . . . . . . . . . . . . . . . . . . . . . . 292
10 Rendering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
10.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
10.2 CIE-Based Colour to Device Colour Colour . . . . . 297
10.3 Conversions among Device . . . . . 297
10.4 Transfer Functions . . . . . . . . . . . . . . . . . . 300
10.5 Halftones . . . . . . . . . . . . . . . . . . . . . . . . . . 301
10.6 Scan Conversion Details . . . . . . . . . . . . . . 316
11 Transparency . . . . . . . . . . . . . . . . . . . . . . . . 320
11.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
11.2 Overview of Transparency . . . . . . . . . . . . 320
11.3 Basic Compositing Computations . . . . . . 322
11.4 Transparency Groups. . . . . . . . . . . . . . . . . 332
11.5 Soft Masks . . . . . . . . . . . . . . . . . . . . . . . . . 342
11.6 Specifying Transparency in PDF. . . . . . . . 344
11.7 Colour Space and Rendering Issues. . . . . . 353
12 Interactive Features . . . . . . . . . . . . . . . . . . . . 362
12.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
12.2 Viewer Preferences. . . . . . . . . . . . . . . . . . 362
12.3 Document-Level Navigation. . . . . . . . . . . 365
12.4 Page-Level Navigation . . . . . . . . . . . . . . . . 374
12.5 Annotations . . . . . . . . . . . . . . . . . . . . . . . . 381
12.6 Actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . 414
12.7 Interactive Forms . . . . . . . . . . . . . . . . . . . . 430
12.8 Digital Signatures . . . . . . . . . . . . . . . . . . . . 466
12.9 Measurement Properties . . . . . . . . . . . . . 479
12.10 Document Requirements . . . . . . . . . . . . . 484
13 Multimedia Features . . . . . . . . . . . . . . . . . . . . . . . . 13 Multimedia Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 486
13.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . 486
13.2 Multimedia . . . . . . . . . . . . . . . . . . . . . . . . . 486
13.3 Sounds. . . . . . . . . . . . . . . . . . . . . . . . . . . . 506
13.4 Movies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507
13.5 Alternate Presentations . . . . . . . . . . . . . . 509
13.6 3D Artwork. . . . . . . . . . . . . . . . . . . . . . . . . 511
14 Document Interchange . . . . . . . . . . . . . . . . . 547
14.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . 547
14.2 Procedure Sets . . . . . . . . . . . . . . . . . . . . . . 547
14.3 Metadata. . . . . . . . . . . . . . . . . . . . . . . . . . . 548
14.4 File Identifiers . . . . . . . . . . . . . . . . . . . . . . 551
14.5 Page-Piece Dictionaries . . . . . . . . . . . . . . . 551
14.6 Marked Content. . . . . . . . . . . . . . . . . . . . . . 552
14.7 Logical Structure. . . . . . . . . . . . . . . . . . . . 556
14.8 Tagged PDF. . . . . . . . . . . . . . . . . . . . . . . . 573
14.9 Accessibility Support . . . . . . . . . . . . . . . . 610
14.10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Capture616
14.11 Prepress Support . . . . . . . . . . . . . . . . . . 627
Annex A Annex A
(informative) Operator Summary. . . . . . . . . . . . . . . . . . . . . . . . 643
Annex B Annex B
(normative) Operators in Type 4 Functions . . . . . . . . . . . . . . . . . . . . . . . . . (normative) Operators in Type 4 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 647
(normative)
Implementation Limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . 649
Annex D (normative)
Character Sets and Encodings. . . . . . . . . . . . . . . . . . . . . 651
Annex E (normative)
PDF Name Registry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 673
Annex F (normative)
Linearized PDF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 675
Annex G (informative)
Linearized PDF Access Strategies. . . . . . . . . . . . . . . . . . 695
Annex H (informative)
Example PDF Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 699
Annex I (normative)
PDF Versions and Compatibility . . . . . . . . . . . . . . . . . . . 727
Annex J (informative)
FDF Rename Flag Implementation Example . . . . . . . . . . 729
Annex K (informative)
PostScript Compatibility -Transparent Imaging Model. . 731
Annex L (informative)
Colour Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 733
Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 745

Foreword

On January 29, 2007, Adobe Systems Incorporated announced it's intention to release the full Portable Document Format (PDF) 1.7 specification to the American National Standard Institute (ANSI) and the Enterprise Content Management Association (AIIM), for the purpose of publication by the International Organization for Standardization (ISO).

PDF has become a de facto global standard for more secure and dependable information exchange since Adobe published the complete PDF specification in 1993. Both government and private industry have come to rely on PDF for the volumes of electronic records that need to be more securely and reliably shared, managed, and in some cases preserved for generations. Since 1995 Adobe has participated in various working groups that develop technical specifications for publication by ISO and worked within the ISO process to deliver specialized subsets of PDF as standards for specific industries and functions. Today, PDF for Archive (PDF/A) and PDF for Exchange (PDF/X) are ISO standards, and PDF for Engineering (PDF/E) and PDF for Universal Access (PDF/UA) are proposed standards. Additionally, PDF for Healthcare (PDF/H) is an AIIM proposed Best Practice Guide. AIIM serves as the administrator for PDF/A, PDF/E, PDF/UA and PDF/H.

In the spring of 2008 the ISO 32000 document was prepared by Adobe Systems Incorporated (based upon PDF Reference, sixth edition, Adobe Portable Document Format version 1.7, November 2006) and was reviewed, edited and adopted, under a special 'fast-track procedure', by Technical Committee ISO/TC 171, Document management application , Subcommittee SC 2, Application issues , in parallel with its approval by the ISO member bodies.

In January 2008, this ISO technical committee approved the final revised documentation for PDF 1.7 as the international standard ISO 32000-1. In July 2008 the ISO document was placed for sale on the ISO web site (http://www.iso.org).

This document you are now reading is a copy of the ISO 32000-1 standard. By agreement with ISO, Adobe Systems is allowed to offer this version of the ISO standard as a free PDF file on it's web site. It is not an official ISO document but the technical content is identical including the section numbering and page numbering.

Introduction

ISO 32000 specifies a digital form for representing documents called the Portable Document Format or usually referred to as PDF. PDF was developed and specified by Adobe Systems Incorporated beginning in 1993 and continuing until 2007 when this ISO standard was prepared. The Adobe Systems version PDF 1.7 is the basis for this ISO 32000 edition. The specifications for PDF are backward inclusive, meaning that PDF 1.7 includes all of the functionality previously documented in the Adobe PDF Specifications for versions 1.0 through 1.6. It should be noted that where Adobe removed certain features of PDF from their standard, they too are not contained herein.

The goal of PDF is to enable users to exchange and view electronic documents easily and reliably, independent of the environment in which they were created or the environment in which they are viewed or printed. At the core of PDF is an advanced imaging model derived from the PostScript® page description language. This PDF Imaging Model enables the description of text and graphics in a device-independent and resolution-independent manner. To improve performance for interactive viewing, PDF defines a more structured format than that used by most PostScript language programs. Unlike Postscript, which is a programming language, PDF is based on a structured binary file format that is optimized for high performance in interactive viewing. PDF also includes objects, such as annotations and hypertext links, that are not part of the page content itself but are useful for interactive viewing and document interchange.

PDF files may be created natively in PDF form, converted from other electronic formats or digitized from paper, microform, or other hard copy format. Businesses, governments, libraries, archives and other institutions and individuals around the world use PDF to represent considerable bodies of important information.

Over the past fourteen years, aided by the explosive growth of the Internet, PDF has become widely used for the electronic exchange of documents. There are several specific applications of PDF that have evolved where limiting the use of some features of PDF and requiring the use of others, enhances the usefulness of PDF. ISO 32000 is an ISO standard for the full function PDF; the following standards are for more specialized uses. PDF/ X (ISO 15930) is now the industry standard for the intermediate representation of printed material in electronic prepress systems for conventional printing applications. PDF/A (ISO 19005) is now the industry standard for the archiving of digital documents. PDF/E (ISO 24517) provides a mechanism for representing engineering documents and exchange of engineering data. As major corporations, government agencies, and educational institutions streamline their operations by replacing paper-based workflow with electronic exchange of information, the impact and opportunity for the application of PDF will continue to grow at a rapid pace.

PDF, together with software for creating, viewing, printing and processing PDF files in a variety of ways, fulfils a set of requirements for electronic documents including:

  • preservation of document fidelity independent of the device, platform, and software,
  • merging of content from diverse sources-Web sites, word processing and spreadsheet programs, scanned documents, photos, and graphics-into one self-contained document while maintaining the integrity of all original source documents,
  • collaborative editing of documents from multiple locations or platforms,
  • digital signatures to certify authenticity,
  • security and permissions to allow the creator to retain control of the document and associated rights,
  • accessibility of content to those with disabilities,
  • extraction and reuse of content for use with other file formats and applications, and
  • electronic forms to gather data and integrate it with business systems.

The International Organization for Standardization draws attention to the fact that it is claimed that compliance with this document may involve the use of patents concerning the creation, modification, display and processing of PDF files which are owned by the following parties:

  • Adobe Systems Incorporated, 345 Park Avenue, San Jose, California,95110-2704, USA

ISO takes no position concerning the evidence, validity and scope of these patent rights.

The holders of these patent rights has assured the ISO that they are willing to negotiate licenses under reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this respect, the statements of the holders of these patent rights are registered with ISO. Information may be obtained from those parties listed above.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights other than those identified above. ISO shall not be held responsible for identifying any or all such patent rights.

A repository of referenced documents has been established by AIIM (http://www.aiim.org/pdfrefdocs). Not all referenced documents can be found there because of copyright restrictions.

Document management - Portable document format -

Part 1: PDF 1.7

IMPORTANT - The electronic file of this document contains colours which are considered to be useful for the correct understanding of the document. Users should therefore consider printing this document using a colour printer.

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