Portable Document Format Reference Manual, Version 1.2

Contents
Figures
	Figure 2.1 Creating PDF files using PDF Writer 30
	Figure 2.2 Creating PDF files using the Distiller ...
	Figure 2.3 Viewing and printing a PDF document 31
	Figure 2.4 PDF components 36
	Figure 3.1 Device space 38
	Figure 3.2 User space 38
	Figure 3.3 Relationships among PDF coordinate syst...
	Figure 3.4 Effects of coordinate transformations 4...
	Figure 3.5 Effect of the order of transformations ...
	Figure 5.1 Structure of a PDF file that has not be...
	Figure 5.2 Structure of a PDF file after changes h...
	Figure 6.1 Structure of a PDF document 76
	Figure 6.2 Page object’s media box and crop box 83...
	Figure 7.1 Fonts, encodings, CMaps, and descriptor...
	Figure 7.2 Characteristics represented in the Flag...
	Figure 7.3 Color spaces 172
	Figure 7.4 Mapping with the Decode array 192
	Figure 7.5 Star Pattern 208
	Figure 8.1 Graphics Objects 212
	Figure 8.2 Flatness 215
	Figure 8.3 Line cap styles 216
	Figure 8.4 Line dash pattern 216
	Figure 8.5 Line join styles 217
	Figure 8.6 Miter length 218
	Figure 8.7 Bézier curve 224
	Figure 8.8 v operator 225
	Figure 8.9 y operator 226
	Figure 8.10 Non-zero winding number rule 227
	Figure 8.11 Even–odd rule 227
	Figure 8.12 Character spacing 230
	Figure 8.13 Effect of word spacing 230
	Figure 8.14 Horizontal scaling 231
	Figure 8.15 Leading 231
	Figure 8.16 Text rendering modes 232
	Figure 8.17 Text rise 233
	Figure 8.18 Operation of TJ operator 237
	Figure 11.1 Restoring clipping path after clipping...
	Figure 13.1 Effect of JPEG encoding on a screensho...
	Figure 13.2 Effect of JPEG encoding on a continuou...
	Figure 14.1 Clipping to a path 302
	Figure 14.2 Using text as a clipping path 303
	Figure 14.3 Images and image masks 306
	Figure 14.4 Using an image to produce a linear ble...
	Figure 14.5 Using an image to produce a square ble...
	Figure A.1 Pages tree for 62-page document example...
	Figure A.2 Example of outline with six items, all ...
	Figure A.3 Example of outline with six items, five...
Tables
	Table 4.1 Escape sequences in strings 46
	Table 4.2 Stream attributes 51
	Table 4.3 Standard filters 51
	Table 4.4 Optional parameters for LZW filter 55
	Table 4.5 Optional parameters for FlateDecode filt...
	Table 4.6 Predictor values 58
	Table 4.7 Optional parameters for CCITTFaxDecode f...
	Table 5.1 Trailer attributes 69
	Table 6.1 Catalog attributes 78
	Table 6.2 Viewer Preferences 79
	Table 6.3 Pages attributes 80
	Table 6.4 Page attributes 81
	Table 6.5 Transition attributes 85
	Table 6.6 Transition Effects 85
	Table 6.7 Effect parameters 86
	Table 6.8 Annotation attributes (common to all ann...
	Table 6.9 Border Style attributes 89
	Table 6.10 Highlight Modes 90
	Table 6.11 Appearance dictionary 91
	Table 6.12 Text annotation attributes (in addition...
	Table 6.13 Link annotation attributes (in addition...
	Table 6.14 Movie Player annotation attributes (in ...
	Table 6.15 Movie dictionary attributes 94
	Table 6.16 Movie Activation attributes 94
	Table 6.17 Sound annotation attributes (in additio...
	Table 6.18 Outlines attributes 96
	Table 6.19 Outline entry attributes 97
	Table 6.20 Destination specification 99
	Table 6.21 Types of actions 100
	Table 6.22 Action attributes (common to all action...
	Table 6.23 Additional Actions attributes 102
	Table 6.24 GoTo action attributes (in addition to ...
	Table 6.25 GoToR action attributes (in addition to...
	Table 6.26 Launch action attributes (in addition t...
	Table 6.27 Windows-specific launch attributes 105
	Table 6.28 Thread action attributes (in addition t...
	Table 6.29 URI action attributes (in addition to t...
	Table 6.30 URI attributes 108
	Table 6.31 Sound action attributes (in addition to...
	Table 6.32 Movie Player attributes (in addition to...
	Table 6.33 SetState action attributes (in addition...
	Table 6.34 Hide action attributes (in addition to ...
	Table 6.35 Named Action Attributes (in addition to...
	Table 6.36 Named Action List 110
	Table 6.37 NOP Action Attributes (in addition to t...
	Table 6.38 Names dictionary in the Catalog 111
	Table 6.39 The root node in a name tree 112
	Table 6.40 An intermediate node in a name tree 112...
	Table 6.41 A leaf node in a name tree 112
	Table 6.42 PDF Info dictionary attributes 114
	Table 6.43 Thread attributes 115
	Table 6.44 Bead attributes 116
	Table 6.45 Standard security handler attributes 11...
	Table 6.46 Permission flags 119
	Table 6.47 AcroForm dictionary attributes 122
	Table 6.48 Attributes common to all types of field...
	Table 6.49 Attributes common to all types of field...
	Table 6.50 Field flags for Btn fields 127
	Table 6.51 checkbox attributes 128
	Table 6.52 Radio button attributes 129
	Table 6.53 Choice attributes 130
	Table 6.54 Field flags for choice fields 131
	Table 6.55 Text field attributes 132
	Table 6.56 SubmitForm action attributes (in additi...
	Table 6.57 ResetForm action attributes (in additio...
	Table 6.58 ImportData action attributes (in additi...
	Table 6.59 Sound attributes 135
	Table 7.1 Examples of file specifications 139
	Table 7.2 File specification attributes 140
	Table 7.3 Predefined procsets 143
	Table 7.4 Attributes common to all types of fonts ...
	Table 7.5 Type 1 font additional attributes 147
	Table 7.6 Base 14 fonts 147
	Table 7.7 Multiple master Type 1 font additional a...
	Table 7.8 Type 3 font additional attributes 150
	Table 7.9 TrueType font attributes 151
	Table 7.10 Type 0 font attributes 152
	Table 7.11 Attributes common to all CID fonts 154
	Table 7.12 CIDFontType 0 font attributes (in addit...
	Table 7.13 CIDFontType 2 font attributes 156
	Table 7.14 Font encoding attributes 157
	Table 7.15 Predefined CJK CMap names 159
	Table 7.16 CMap attributes 160
	Table 7.17 Font descriptor attributes 163
	Table 7.18 Additional attributes for FontFile stre...
	Table 7.19 Font flags 166
	Table 7.20 Additional FontDescriptor attributes 16...
	Table 7.21 Character Subsets in CJK fonts 169
	Table 7.22 CID font file 171
	Table 7.23 CalGray attributes 173
	Table 7.24 CalRGB attributes 174
	Table 7.25 Lab attributes 175
	Table 7.26 Image XObject attributes 178
	Table 7.27 Default Decode arrays for various color...
	Table 7.28 Color rendering intents 181
	Table 7.29 Form XObject attributes 182
	Table 7.30 PostScript XObject attributes 184
	Table 7.31 OPI dictionary 185
	Table 7.32 OPI 1.3 dictionary 185
	Table 7.33 OPI 2.0 dictionary 186
	Table 7.34 Function dictionary attributes shared b...
	Table 7.35 Attributes of sampled functions (Functi...
	Table 7.36 ExtGState attributes 191
	Table 7.37 Entries in a Type 1 halftone dictionary...
	Table 7.38 Predefined spot functions 195
	Table 7.39 Entries in a Type 5 halftone dictionary...
	Table 7.40 Type 6 halftone attributes 202
	Table 7.41 Type 10 halftone attributes 203
	Table 7.42 Pattern attributes 204
	Table 7.43 Property List attributes 209
	Table 8.1 Abbreviations for in-line image names 23...
	Table 9.1 Linearization parameters 251
	Table 9.2 Standard Hint Tables 254
	Table 9.3 Page Offset hint table, header section 2...
	Table 9.4 Page Offset hint table, per-page entry 2...
	Table 9.5 Shared Object hint table, header section...
	Table 9.6 Shared Object hint table, Shared Object ...
	Table 9.7 Thumbnails hint table, header section 26...
	Table 9.8 Thumbnails hint table, per-page entry 26...
	Table 9.9 Generic Hint Table 264
	Table 9.10 Forms hint table, continued 264
	Table 10.1 Optimized operator combinations 273
	Table 11.1 Comparison of text string operators 283...
	Table 11.2 Comparison of text positioning operator...
	Table 13.1 Comparison of compression filters for i...
	Table A.1 Objects in empty example 315
	Table A.2 Objects in “Hello World” example 317
	Table A.3 Objects in graphics example 319
	Table A.4 Object use after adding four text annota...
	Table A.5 Object use after deleting two text annot...
	Table A.6 Object use after adding three text annot...
	Table B.1 PDF page marking operators 335
	Table D.1 Architectural limits 356
	Table G.1 Acrobat 1.0 Viewer behavior with unknown...
	Table G.2 Acrobat 2.0 Viewer behavior with unknown...
	Table H.1 FDF attributes 376
	Table H.2 Field attributes 377
Examples
	Example 4.1 Dictionary 49
	Example 4.2 Dictionary within a dictionary 49
	Example 4.3 Stream that has been LZW and ASCII85 e...
	Example 4.4 Unencoded stream 52
	Example 4.1 Indirect reference 63
	Example 5.1 Cross-reference section with a single ...
	Example 5.2 Cross-reference section with multiple ...
	Example 5.3 Trailer 70
	Example 6.1 Catalog 77
	Example 6.2 Pages tree for a document containing t...
	Example 6.3 Inheritance of attributes 81
	Example 6.4 Page with thumbnail, annotations, and ...
	Example 6.5 A page with information for presentati...
	Example 6.6 Thumbnail 87
	Example 6.7 Text annotation 92
	Example 6.8 Link annotation 93
	Example 6.9 Outlines object with six open entries ...
	Example 6.10 Outline entry 98
	Example 6.11 GoTo action 104
	Example 6.1 Info dictionary 115
	Example 6.2 Thread 116
	Example 6.3 Simple checkbox field 128
	Example 6.4 Radio button field with two buttons 12...
	Example 6.5 List box field 131
	Example 6.6 Text field 132
	Example 7.1 URLs 141
	Example 7.2 Resources dictionary 143
	Example 7.1 Type 1 font and character widths array...
	Example 7.2 Multiple master font and character wid...
	Example 7.3 Type 3 font 151
	Example 7.4 TrueType font 152
	Example 7.5 Type 0 font referring to a single CID ...
	Example 7.6 Font encoding 158
	Example 7.7 CMap Encoding 161
	Example 7.8 Embedded Type 1 font definition 165
	Example 7.1 Font descriptor 167
	Example 7.2 FD entry 170
	Example 7.3 Indexed color space 176
	Example 7.4 Image with length specified as an indi...
	Example 7.1 Form XObject 183
	Example 7.2 Example of a spot function 190
	Example 7.3 ExtGStates 192
	Example 7.4 Halftone with spot-function dictionary...
	Example 7.5 Halftone dictionary for type 5 200
	Example 7.6 Bitmap pattern 205
	Example 7.7 Star pattern 206
	Example 8.1 In-line image 240
	Example 9.1 Outline of a linearized PDF file 249
	Example 11.1 Changing the text matrix inside a tex...
	Example 11.2 Multiple lines of text without automa...
	Example 11.3 Multiple lines of text using automati...
	Example 11.4 TJ operator without automatic leading...
	Example 11.5 Use of the T* operator 281
	Example 11.6 Using the TL operator to set leading ...
	Example 11.7 Using the TD operator to set leading ...
	Example 11.8 Character and word spacing using the ...
	Example 11.9 Character and word spacing using the ...
	Example 11.1 Restoring clipping path after using t...
	Example 12.1 Each path segment as a separate path ...
	Example 12.2 Grouping path segments into a single ...
	Example 12.3 Using redundant l and h operators to ...
	Example 12.4 Using the l operator to close a path ...
	Example 12.5 Taking advantage of the h operator to...
	Example 12.6 Improperly closing a path: multiple p...
	Example 12.7 Properly closing a path: single path ...
	Example 12.8 Portion of a path before coalescing o...
	Example 12.9 Portion of a path after coalescing op...
	Example 14.1 Clipping to a path 302
	Example 14.2 Using text as a clipping path 304
	Example 14.3 Images and image masks 306
	Example 14.4 Using images as blends 309
	Example 14.5 Image used to produce a grayscale squ...
	Example A.1 Minimal PDF file 316
	Example A.2 PDF file for simple text example 317
	Example A.3 PDF file for simple graphics example 3...
	Example A.4 Pages tree for a document containing 6...
	Example A.5 Six entry outline, all items open 324
	Example A.6 Six entry outline, five entries open 3...
	Example A.7 Update section of PDF file when four t...
	Example A.8 Update section of PDF file when one te...
	Example A.9 Update section of PDF file when two te...
	Example A.10 Update section of PDF file after thre...
Introduction
	1.1 About this book
	1.2 Introduction to the Second Edition—PDF 1.1
	1.3 Introduction to the Third Edition—PDF 1.2
	1.4 Conventions used in this book
	1.5 A note on syntax
	1.6 Copyrights and permissions to use PDF
Portable Document Format
Overview
	2.1 What is the Portable Document Format?
	2.2 Using PDF
	2.3 General properties
	2.4 PDF and the PostScript language
	2.5 Understanding PDF
Coordinate Systems
	3.1 Device space
	3.2 User space
	3.3 Text space
	3.4 Character space
	3.5 Image space
	3.6 Form space
	3.7 Pattern space
	3.8 Relationships among coordinate systems
	3.9 Transformations between coordinate systems
	3.10 Transformation matrices
Objects
	4.1 Introduction
	4.2 Booleans
	4.3 Numbers
	4.4 Strings
	4.5 Names
	4.6 Arrays
	4.7 Dictionaries
	4.8 Streams
	4.9 The null object
	4.10 Indirect objects
	4.11 Object references
File Structure
	5.1 PDF files
	5.2 Header
	5.3 Body
	5.4 Cross-reference table
	5.5 Trailer
	5.6 Incremental update
	5.7 Encryption
Document Structure
	6.1 Introduction
	6.2 Catalog
	6.3 Pages tree
	6.4 Page objects
	6.5 Thumbnails
	6.6 Annotations
	6.7 Outline tree
	6.8 Destinations
	6.9 Actions
	6.10 Name trees
	6.11 Info dictionary
	6.12 Articles
	6.13 File ID
	6.14 Encryption dictionary
	6.15 Acrobat Forms
	6.16 Sounds
Common Data Structures
	7.1 Rectangle
	7.2 File specification
	7.3 Resource Dictionaries
	7.4 ProcSets
	7.5 Fonts
	7.6 Font encodings
	7.7 CMaps
	7.8 Font descriptors
	7.9 Color spaces
	7.10 XObjects
	7.11 Functions
	7.12 Extended graphics states
	7.13 Halftones
	7.14 Patterns
	7.15 Property lists
Page Descriptions
	8.1 Overview
	8.2 Graphics state
	8.3 Special Graphics State
	8.4 General Graphics state
	8.5 Color
	8.6 Paths
	8.7 Text state
	8.8 External objects (XObjects)
	8.9 In-line image objects
	8.10 Other operators
Linearized PDF
	9.1 Introduction
	9.2 Background and Assumptions
	9.3 Linearized PDF document structure specificatio...
	9.4 Hint Tables
	9.5 Access Strategies
Optimizing PDF Files
General Techniques for Optimizing PDF Files
	10.1 Use short names
	10.2 Use direct and indirect objects appropriately...
	10.3 Take advantage of combined operators
	10.4 Remove unnecessary clipping paths
	10.5 Omit unnecessary spaces
	10.6 Omit default values
	10.7 Take advantage of forms
	10.8 Limit the precision of real numbers
	10.9 Write parameters only when they change
	10.10 Don’t draw outside the crop box
	10.11 Consider target device resolution
	10.12 Share resources
	10.13 Store common Page attributes in the Pages ob...
	10.14 Use strings for named destinations
Optimizing Text
	11.1 Don’t produce unnecessary text objects
	11.2 Use automatic leading
	11.3 Take advantage of text spacing operators
	11.4 Don’t replace spaces between words
	11.5 Use the appropriate operator to draw text
	11.6 Use the appropriate operator to position text...
	11.7 Remove text clipping
	11.8 Consider target device resolution
Optimizing Graphics
	12.1 Use the appropriate color-setting operator
	12.2 Defer path painting until necessary
	12.3 Take advantage of the closepath operator
	12.4 Don’t close a path more than once
	12.5 Don’t draw zero-length lines
	12.6 Make sure drawing is needed
	12.7 Take advantage of rectangle and curve operato...
	12.8 Coalesce operations
Optimizing Images
	13.1 Preprocess images
	13.2 Match image resolution to target device resol...
	13.3 Use the minimum number of bits per color comp...
	13.4 Take advantage of indexed color spaces
	13.5 Use the DeviceGray color space for monochrome...
	13.6 Use in-line images appropriately
	13.7 Don’t compress in-line images unnecessarily
	13.8 Choose the appropriate filters
	13.9 Use predefined spot functions
Clipping and Blends
	14.1 Clipping to a path
	14.2 Clipping to text
	14.3 Image masks
	14.4 Blends
Example PDF Files
	A.1 Minimal PDF file
	A.2 Simple text string
	A.3 Simple graphics
	A.4 Pages tree
	A.5 Outline
	A.6 Updated file
Summary of Page Marking Operators
Predefined Font Encodings
	C.1 Predefined encodings sorted by character name
	C.2 Predefined encodings sorted by character code
	C.3 MacExpert encoding
Implementation Limits
Obtaining XUIDs and Technical Notes
PDF Name Registry
Compatibility and Implementation Notes
	G.1 Version numbers
	G.2 Dictionary keys
	G.3 Implementation notes
Forms Data Format
	H.1 File Structure
	H.2 The FDF Catalog Object
	H.3 Use of FDF
	H.4 Sample FDF
ISO 639 Language Codes
ISO 3166 Country Codes
Bibliography
Colophon