pdfcpu

package
v0.1.14 Latest Latest
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 Go to latest Published: Jun 9, 2018 License: MIT Imports: 31 Imported by: 0

Documentation

Overview

Package pdfcpu is a simple PDF processing library written in Go supporting encryption. It provides an API and a command line interface. Supported are all versions up to PDF 1.7 (ISO-32000).

The available commands are: 

validate	validate PDF against PDF 32000-1:2008 (PDF 1.7)
optimize	optimize PDF by getting rid of redundant page resources
split		split multi-page PDF into several single-page PDFs
merge		concatenate 2 or more PDFs
extract		extract images, fonts, content or pages
trim		create trimmed version
attach		list, add, remove, extract embedded file attachments
perm		list, add user access permissions
encrypt		set password protection
decrypt		remove password protection
changeupw	change user password
changeopw	change owner password
version		print version

Index

Constants

View Source 
const (

	// ValidationStrict ensures 100% compliance with the spec (PDF 32000-1:2008).
	ValidationStrict = 0

	// ValidationRelaxed ensures PDF compliance based on frequently encountered validation errors.
	ValidationRelaxed = 1

	// StatsFileNameDefault is the standard stats filename.
	StatsFileNameDefault = "stats.csv"

	// PermissionsAll enables all user access permission bits.
	PermissionsAll int16 = -1 // 0xFFFF

	// PermissionsNone disables all user access permissions bits.
	PermissionsNone int16 = -3901 // 0xF0C3

)
View Source 
const (
	RootVersion = iota
	RootExtensions
	RootPageLabels
	RootNames
	RootDests
	RootViewerPrefs
	RootPageLayout
	RootPageMode
	RootOutlines
	RootThreads
	RootOpenAction
	RootAA
	RootURI
	RootAcroForm
	RootMetadata
	RootStructTreeRoot
	RootMarkInfo
	RootLang
	RootSpiderInfo
	RootOutputIntents
	RootPieceInfo
	RootOCProperties
	RootPerms
	RootLegal
	RootRequirements
	RootCollection
	RootNeedsRendering
)

The PDF root object fields.

View Source 
const (
	PageLastModified = iota
	PageResources
	PageMediaBox
	PageCropBox
	PageBleedBox
	PageTrimBox
	PageArtBox
	PageBoxColorInfo
	PageContents
	PageRotate
	PageGroup
	PageThumb
	PageB
	PageDur
	PageTrans
	PageAnnots
	PageAA
	PageMetadata
	PagePieceInfo
	PageStructParents
	PageID
	PagePZ
	PageSeparationInfo
	PageTabs
	PageTemplateInstantiated
	PagePresSteps
	PageUserUnit
	PageVP
)

The PDF page object fields.

View Source 
const (
	EolLF   = "\x0A"
	EolCR   = "\x0D"
	EolCRLF = "\x0D\x0A"
)

Supported line delimiters

View Source 
const (
	DeviceGrayCS = "DeviceGray"
	DeviceRGBCS  = "DeviceRGB"
	DeviceCMYKCS = "DeviceCMYK"
	CalGrayCS    = "CalGray"
	CalRGBCS     = "CalRGB"
	LabCS        = "Lab"
	ICCBasedCS   = "ICCBased"
	IndexedCS    = "Indexed"
	PatternCS    = "Pattern"
	SeparationCS = "Separation"
	DeviceNCS    = "DeviceN"
)

PDF defines the following Color Spaces:

View Source 
const (

	// REQUIRED is used for required dict entries.
	REQUIRED = true

	// OPTIONAL is used for optional dict entries.
	OPTIONAL = false
)
View Source 
const (

	// ExcludePatternCS ...
	ExcludePatternCS = true

	// IncludePatternCS ...
	IncludePatternCS = false
)
View Source 
const (
	// PDFCPUVersion returns the current pdfcpu version.
	PDFCPUVersion = "0.1.14"

	// PDFCPULongVersion returns pdfcpu's signature.
	PDFCPULongVersion = "golang pdfcpu v" + PDFCPUVersion
)
View Source 
const FreeHeadGeneration = 65535

FreeHeadGeneration is the predefined generation number for the head of the free list.

View Source 
const (

	// ObjectStreamMaxObjects limits the number of objects within an object stream written.
	ObjectStreamMaxObjects = 100
)

Variables

View Source 
var (
	ErrUnsupportedColorSpace = errors.New("unsupported color space")
	ErrUnsupportedBPC        = errors.New("unsupported bitsPerComponent")
)

Errors to be identified.

Functions

func AppendStatsFile 

func AppendStatsFile(ctx *PDFContext) error

AppendStatsFile appends a stats line for this xRefTable to the configured csv file name.

func AttachAdd 

func AttachAdd(xRefTable *XRefTable, files StringSet) (ok bool, err error)

AttachAdd embeds specified files. Existing attachments are replaced. ok returns true if at least one attachment was added.

func AttachExtract 

func AttachExtract(ctx *PDFContext, files StringSet) (err error)

AttachExtract exports specified embedded files. If no files specified extract all embedded files.

func AttachList 

func AttachList(xRefTable *XRefTable) (list []string, err error)

AttachList returns a list of embedded files.

func AttachRemove 

func AttachRemove(xRefTable *XRefTable, files StringSet) (ok bool, err error)

AttachRemove deletes specified embedded files. ok returns true if at least one attachment could be removed.

func CreateDemoPDF 

func CreateDemoPDF(xRefTable *XRefTable, dirName, fileName string) error

CreateDemoPDF creates a demo PDF file for testing validation.

func Date 

func Date(s string) bool

Date validates an ISO/IEC 8824 compliant date string.

func DecodeUTF16String 

func DecodeUTF16String(s string) (string, error)

DecodeUTF16String decodes a UTF16BE string from a hex string.

func Escape 

func Escape(s string) (*string, error)

Escape applies all defined escape sequences to s.

func ExtractContentData 

func ExtractContentData(ctx *PDFContext, objNr int) (data []byte, err error)

ExtractContentData extracts page content in PDF notation for objNr.

func HexLiteralToString 

func HexLiteralToString(hexString string) (string, error)

HexLiteralToString returns a possibly UTF16 encoded string for a hex string.

func IsStringUTF16BE 

func IsStringUTF16BE(s string) bool

IsStringUTF16BE checks a string for Big Endian byte order BOM.

func IsUTF16BE 

func IsUTF16BE(b []byte) (ok bool, err error)

IsUTF16BE checks for Big Endian byte order mark.

func MergeXRefTables 

func MergeXRefTables(ctxSource, ctxDest *PDFContext) (err error)

MergeXRefTables merges PDFContext ctxSource into ctxDest by appending its page tree.

func OptimizeXRefTable 

func OptimizeXRefTable(ctx *PDFContext) error

OptimizeXRefTable optimizes an xRefTable by locating and getting rid of redundant embedded fonts and images.

func Permissions 

func Permissions(ctx *PDFContext) (list []string)

Permissions returns a list of set permissions.

func StringLiteralToString 

func StringLiteralToString(s string) (string, error)

StringLiteralToString returns the best possible string rep for a string literal.

func Unescape 

func Unescape(s string) ([]byte, error)

Unescape resolves all escape sequences of s.

func ValidateXRefTable 

func ValidateXRefTable(xRefTable *XRefTable) error

ValidateXRefTable validates a PDF cross reference table obeying the validation mode.

func VersionString 

func VersionString(version PDFVersion) string

VersionString returns a string representation for a given PDFVersion.

func WritePDFFile 

func WritePDFFile(ctx *PDFContext) error

WritePDFFile generates a PDF file for the cross reference table contained in PDFContext.

func WritePNGFile added in v0.1.14 

func WritePNGFile(ctx *PDFContext, fileName string, objNr int, io *ImageObject) error

WritePNGFile creates a PNG file for an image object.

Types

type ByteSize 

type ByteSize float64

ByteSize represents the various terms for storage space. 

const (
	KB ByteSize = 1 << (10 * iota)
	MB
	GB
)

Storage space terms.

func (ByteSize) String 

func (b ByteSize) String() string

type CommandMode 

type CommandMode int

CommandMode specifies the operation being executed. 

const (
	VALIDATE CommandMode = iota
	OPTIMIZE
	SPLIT
	MERGE
	EXTRACTIMAGES
	EXTRACTFONTS
	EXTRACTPAGES
	EXTRACTCONTENT
	TRIM
	ADDATTACHMENTS
	REMOVEATTACHMENTS
	EXTRACTATTACHMENTS
	LISTATTACHMENTS
	ADDPERMISSIONS
	LISTPERMISSIONS
	ENCRYPT
	DECRYPT
	CHANGEUPW
	CHANGEOPW
)

The available commands.

type Configuration 

type Configuration struct {

	// Enables PDF V1.5 compatible processing of object streams, xref streams, hybrid PDF files.
	Reader15 bool

	// Enables decoding of all streams (fontfiles, images..) for logging purposes.
	DecodeAllStreams bool

	// Validate against ISO-32000: strict or relaxed
	ValidationMode int

	// End of line char sequence for writing.
	Eol string

	// Turns on object stream generation.
	// A signal for compressing any new non-stream-object into an object stream.
	// true enforces WriteXRefStream to true.
	// false does not prevent xRefStream generation.
	WriteObjectStream bool

	// Switches between xRefSection (<=V1.4) and objectStream/xRefStream (>=V1.5) writing.
	WriteXRefStream bool

	// Turns on stats collection.
	CollectStats bool

	// A CSV-filename holding the statistics.
	StatsFileName string

	// Supplied user password
	UserPW    string
	UserPWNew *string

	// Supplied owner password
	OwnerPW    string
	OwnerPWNew *string

	// EncryptUsingAES ensures AES encryption.
	// true: AES encryption
	// false: RC4 encryption.
	EncryptUsingAES bool

	// EncryptUsing128BitKey ensures 128 bit key length.
	// true: use 128 bit key
	// false: use 40 bit key
	EncryptUsing128BitKey bool

	// Supplied user access permissions, see Table 22
	UserAccessPermissions int16

	// Command being executed.
	Mode CommandMode
}

Configuration of a PDFContext.

func NewDefaultConfiguration 

func NewDefaultConfiguration() *Configuration

NewDefaultConfiguration returns the default pdfcpu configuration.

func (*Configuration) ValidationModeString 

func (c *Configuration) ValidationModeString() string

ValidationModeString returns a string rep for the validation mode in effect.

type Enc 

type Enc struct {
	O, U       []byte
	L, P, R, V int
	Emd        bool // encrypt meta data
	ID         []byte
}

Enc wraps around all defined encryption attributes.

type FontObject 

type FontObject struct {
	ResourceNames []string
	Prefix        string
	FontName      string
	FontDict      *PDFDict
	Data          []byte
	Extension     string
}

FontObject represents a font used in a PDF file.

func ExtractFontData 

func ExtractFontData(ctx *PDFContext, objNr int) (*FontObject, error)

ExtractFontData extracts font data (the "fontfile") for objNr. Supported fontTypes: TrueType

func (*FontObject) AddResourceName 

func (fo *FontObject) AddResourceName(resourceName string)

AddResourceName adds a resourceName referring to this font.

func (FontObject) Embedded 

func (fo FontObject) Embedded() (embedded bool)

Embedded returns true if the font is embedded into this PDF file.

func (FontObject) Encoding 

func (fo FontObject) Encoding() string

Encoding returns the Encoding of this font.

func (FontObject) ResourceNamesString 

func (fo FontObject) ResourceNamesString() string

ResourceNamesString returns a string representation of all the resource names of this font.

func (FontObject) String 

func (fo FontObject) String() string

func (FontObject) SubType 

func (fo FontObject) SubType() string

SubType returns the SubType of this font.

type ImageObject 

type ImageObject struct {
	ResourceNames []string
	ImageDict     *PDFStreamDict
	Extension     string
}

ImageObject represents an image used in a PDF file.

func ExtractImageData 

func ExtractImageData(ctx *PDFContext, objNr int) (*ImageObject, error)

ExtractImageData extracts image data for objNr. Supported imgTypes: DCTDecode, JPXDecode Note: This is a naive implementation that just returns encoded image bytes. Hence TODO: Implementation and usage of these filters: DCTDecode and JPXDecode.

func (*ImageObject) AddResourceName 

func (io *ImageObject) AddResourceName(resourceName string)

AddResourceName adds a resourceName to this imageObject's ResourceNames dict.

func (ImageObject) Data 

func (io ImageObject) Data() []byte

Data returns the raw data belonging to this image object.

func (ImageObject) ResourceNamesString 

func (io ImageObject) ResourceNamesString() string

ResourceNamesString returns a string representation of the ResourceNames for this image.

type IntSet 

type IntSet map[int]bool

IntSet is a set of integers.

type Node 

type Node struct {
	Kids       []*Node         // Mirror of the name tree's Kids array.
	Names      []entry         // Mirror of the name tree's Names array.
	Kmin, Kmax string          // Mirror of the name tree's Limit array[Kmin,Kmax].
	IndRef     *PDFIndirectRef // Pointer to the PDF object representing this name tree node.
}

Node is an opiniated implementation of the PDF name tree. pdfcpu caches all name trees found in the PDF catalog with this data structure. The PDF spec does not impose any rules regarding a strategy for the creation of nodes. A binary tree was chosen where each leaf node has a limited number of entries (maxEntries). Once maxEntries has been reached a leaf node turns into an intermediary node with two kids, which are leaf nodes each of them holding half of the sorted entries of the original leaf node.

func (*Node) Add 

func (n *Node) Add(xRefTable *XRefTable, k string, v PDFObject) error

Add adds an entry to a name tree.

func (*Node) AddToLeaf 

func (n *Node) AddToLeaf(k string, v PDFObject)

AddToLeaf adds an entry to a leaf.

func (Node) KeyList 

func (n Node) KeyList() ([]string, error)

KeyList returns a sorted list of all keys.

func (Node) Process 

func (n Node) Process(xRefTable *XRefTable, handler func(*XRefTable, string, PDFObject) error) error

Process traverses the nametree applying a handler to each entry (key-value pair).

func (*Node) Remove 

func (n *Node) Remove(xRefTable *XRefTable, k string) (empty, ok bool, err error)

Remove removes an entry from a name tree. empty returns true if this node is an empty leaf node after removal. ok returns true if removal was successful.

func (Node) String 

func (n Node) String() string

func (Node) Value 

func (n Node) Value(k string) (PDFObject, bool)

Value returns the value given key

type OptimizationContext 

type OptimizationContext struct {

	// Font section
	PageFonts         []IntSet
	FontObjects       map[int]*FontObject
	Fonts             map[string][]int
	DuplicateFontObjs IntSet
	DuplicateFonts    map[int]*PDFDict

	// Image section
	PageImages         []IntSet
	ImageObjects       map[int]*ImageObject
	DuplicateImageObjs IntSet
	DuplicateImages    map[int]*PDFStreamDict

	DuplicateInfoObjects IntSet // Possible result of manual info dict modification.

	NonReferencedObjs []int // Objects that are not referenced.
}

OptimizationContext represents the context for the optimiziation of a PDF file.

func (*OptimizationContext) DuplicateFontObjectsString 

func (oc *OptimizationContext) DuplicateFontObjectsString() (int, string)

DuplicateFontObjectsString returns a formatted string and the number of objs.

func (*OptimizationContext) DuplicateImageObjectsString 

func (oc *OptimizationContext) DuplicateImageObjectsString() (int, string)

DuplicateImageObjectsString returns a formatted string and the number of objs.

func (*OptimizationContext) DuplicateInfoObjectsString 

func (oc *OptimizationContext) DuplicateInfoObjectsString() (int, string)

DuplicateInfoObjectsString returns a formatted string and the number of objs.

func (*OptimizationContext) IsDuplicateFontObject 

func (oc *OptimizationContext) IsDuplicateFontObject(i int) bool

IsDuplicateFontObject returns true if object #i is a duplicate font object.

func (*OptimizationContext) IsDuplicateImageObject 

func (oc *OptimizationContext) IsDuplicateImageObject(i int) bool

IsDuplicateImageObject returns true if object #i is a duplicate image object.

func (*OptimizationContext) IsDuplicateInfoObject 

func (oc *OptimizationContext) IsDuplicateInfoObject(i int) bool

IsDuplicateInfoObject returns true if object #i is a duplicate info object.

func (*OptimizationContext) NonReferencedObjsString 

func (oc *OptimizationContext) NonReferencedObjsString() (int, string)

NonReferencedObjsString returns a formatted string and the number of objs.

type PDFArray 

type PDFArray []PDFObject

PDFArray represents a PDF array object.

func NewIntegerArray 

func NewIntegerArray(fVars ...int) PDFArray

NewIntegerArray returns a PDFArray with PDFInteger entries.

func NewNameArray 

func NewNameArray(sVars ...string) PDFArray

NewNameArray returns a PDFArray with PDFName entries.

func NewNumberArray 

func NewNumberArray(fVars ...float64) PDFArray

NewNumberArray returns a PDFArray with PDFFloat entries.

func NewRectangle 

func NewRectangle(llx, lly, urx, ury float64) PDFArray

NewRectangle creates a rectangle array

func NewStringArray 

func NewStringArray(sVars ...string) PDFArray

NewStringArray returns a PDFArray with PDFStringLiteral entries.

func (PDFArray) PDFString 

func (array PDFArray) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFArray) String 

func (array PDFArray) String() string

type PDFBoolean 

type PDFBoolean bool

PDFBoolean represents a PDF boolean object.

func (PDFBoolean) PDFString 

func (boolean PDFBoolean) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFBoolean) String 

func (boolean PDFBoolean) String() string

func (PDFBoolean) Value 

func (boolean PDFBoolean) Value() bool

Value returns a bool value for this PDF object.

type PDFContext 

type PDFContext struct {
	*Configuration
	*XRefTable
	Read     *ReadContext
	Optimize *OptimizationContext
	Write    *WriteContext
}

PDFContext represents the context for processing PDF files.

func NewPDFContext 

func NewPDFContext(fileName string, file *os.File, config *Configuration) (*PDFContext, error)

NewPDFContext initializes a new PDFContext.

func ReadPDFFile 

func ReadPDFFile(fileName string, config *Configuration) (*PDFContext, error)

ReadPDFFile reads in a PDFFile and generates a PDFContext, an in-memory representation containing a cross reference table.

func (*PDFContext) ResetWriteContext 

func (ctx *PDFContext) ResetWriteContext()

ResetWriteContext prepares an existing WriteContext for a new file to be written.

func (*PDFContext) String 

func (ctx *PDFContext) String() string

type PDFDict 

type PDFDict struct {
	Dict map[string]PDFObject
}

PDFDict represents a PDF dict object.

func NewPDFDict 

func NewPDFDict() PDFDict

NewPDFDict returns a new PDFDict object.

func (PDFDict) BooleanEntry 

func (d PDFDict) BooleanEntry(key string) *bool

BooleanEntry expects and returns a BooleanEntry for given key.

func (*PDFDict) Delete 

func (d *PDFDict) Delete(key string) (value PDFObject)

Delete deletes the PDFObject for given key.

func (*PDFDict) Entry 

func (d *PDFDict) Entry(dictName, key string, required bool) (PDFObject, error)

Entry returns the value for given key.

func (PDFDict) Find 

func (d PDFDict) Find(key string) (value PDFObject, found bool)

Find returns the PDFObject for given key and PDFDict.

func (PDFDict) First 

func (d PDFDict) First() *int

First returns a *int for key "First".

func (PDFDict) Index 

func (d PDFDict) Index() *PDFArray

Index returns a *PDFArray for key "Index".

func (PDFDict) IndirectRefEntry 

func (d PDFDict) IndirectRefEntry(key string) *PDFIndirectRef

IndirectRefEntry returns an indirectRefEntry for given key for this dictionary.

func (*PDFDict) Insert 

func (d *PDFDict) Insert(key string, value PDFObject) (ok bool)

Insert adds a new entry to this PDFDict.

func (*PDFDict) InsertFloat 

func (d *PDFDict) InsertFloat(key string, value float32)

InsertFloat adds a new float entry to this PDFDict.

func (*PDFDict) InsertInt 

func (d *PDFDict) InsertInt(key string, value int)

InsertInt adds a new int entry to this PDFDict.

func (*PDFDict) InsertName 

func (d *PDFDict) InsertName(key, value string)

InsertName adds a new name entry to this PDFDict.

func (*PDFDict) InsertString 

func (d *PDFDict) InsertString(key, value string)

InsertString adds a new string entry to this PDFDict.

func (PDFDict) Int64Entry 

func (d PDFDict) Int64Entry(key string) *int64

Int64Entry expects and returns a PDFInteger entry representing an int64 value for given key.

func (PDFDict) IntEntry 

func (d PDFDict) IntEntry(key string) *int

IntEntry expects and returns a PDFInteger entry for given key.

func (PDFDict) IsLinearizationParmDict 

func (d PDFDict) IsLinearizationParmDict() bool

IsLinearizationParmDict returns true if this dict has an int entry for key "Linearized".

func (PDFDict) IsObjStm 

func (d PDFDict) IsObjStm() bool

IsObjStm returns true if given PDFDict is an object stream.

func (*PDFDict) Len 

func (d *PDFDict) Len() int

Len returns the length of this PDFDict.

func (PDFDict) Length 

func (d PDFDict) Length() (*int64, *int)

Length returns a *int64 for entry with key "Length". Stream length may be referring to an indirect object.

func (PDFDict) N 

func (d PDFDict) N() *int

N returns a *int for key "N".

func (PDFDict) NameEntry 

func (d PDFDict) NameEntry(key string) *string

NameEntry expects and returns a PDFName entry for given key.

func (PDFDict) PDFArrayEntry 

func (d PDFDict) PDFArrayEntry(key string) *PDFArray

PDFArrayEntry expects and returns a PDFArray entry for given key.

func (PDFDict) PDFDictEntry 

func (d PDFDict) PDFDictEntry(key string) *PDFDict

PDFDictEntry expects and returns a PDFDict entry for given key.

func (PDFDict) PDFHexLiteralEntry 

func (d PDFDict) PDFHexLiteralEntry(key string) *PDFHexLiteral

PDFHexLiteralEntry returns a PDFHexLiteral object for given key.

func (PDFDict) PDFNameEntry 

func (d PDFDict) PDFNameEntry(key string) *PDFName

PDFNameEntry returns a PDFName object for given key.

func (PDFDict) PDFStreamDictEntry 

func (d PDFDict) PDFStreamDictEntry(key string) *PDFStreamDict

PDFStreamDictEntry expects and returns a PDFStreamDict entry for given key. unused.

func (PDFDict) PDFString 

func (d PDFDict) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFDict) PDFStringLiteralEntry 

func (d PDFDict) PDFStringLiteralEntry(key string) *PDFStringLiteral

PDFStringLiteralEntry returns a PDFStringLiteral object for given key.

func (PDFDict) Prev 

func (d PDFDict) Prev() *int64

Prev returns the previous offset.

func (PDFDict) Size 

func (d PDFDict) Size() *int

Size returns the value of the int entry for key "Size"

func (PDFDict) String 

func (d PDFDict) String() string

func (PDFDict) StringEntry 

func (d PDFDict) StringEntry(key string) *string

StringEntry expects and returns a PDFStringLiteral entry for given key. Unused.

func (PDFDict) StringEntryBytes 

func (d PDFDict) StringEntryBytes(key string) ([]byte, error)

StringEntryBytes returns the byte slice representing the string value for key.

func (PDFDict) Subtype 

func (d PDFDict) Subtype() *string

Subtype returns the value of the name entry for key "Subtype".

func (PDFDict) Type 

func (d PDFDict) Type() *string

Type returns the value of the name entry for key "Type".

func (*PDFDict) Update 

func (d *PDFDict) Update(key string, value PDFObject)

Update modifies an existing entry of this PDFDict.

func (PDFDict) W 

func (d PDFDict) W() *PDFArray

W returns a *PDFArray for key "W".

type PDFFilter 

type PDFFilter struct {
	Name        string
	DecodeParms *PDFDict
}

PDFFilter represents a PDF stream filter object.

type PDFFloat 

type PDFFloat float64

PDFFloat represents a PDF float object.

func (PDFFloat) PDFString 

func (f PDFFloat) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFFloat) String 

func (f PDFFloat) String() string

func (PDFFloat) Value 

func (f PDFFloat) Value() float64

Value returns a float64 value for this PDF object.

type PDFHexLiteral 

type PDFHexLiteral string

PDFHexLiteral represents a PDF hex literal object.

func (PDFHexLiteral) Bytes 

func (hexliteral PDFHexLiteral) Bytes() ([]byte, error)

Bytes returns the byte representation.

func (PDFHexLiteral) PDFString 

func (hexliteral PDFHexLiteral) PDFString() string

PDFString returns the string representation as found in and written to a PDF file.

func (PDFHexLiteral) String 

func (hexliteral PDFHexLiteral) String() string

func (PDFHexLiteral) Value 

func (hexliteral PDFHexLiteral) Value() string

Value returns a string value for this PDF object.

type PDFIndirectRef 

type PDFIndirectRef struct {
	ObjectNumber     PDFInteger
	GenerationNumber PDFInteger
}

PDFIndirectRef represents a PDF indirect object.

func NewPDFIndirectRef 

func NewPDFIndirectRef(objectNumber, generationNumber int) *PDFIndirectRef

NewPDFIndirectRef returns a new PDFIndirectRef object.

func (PDFIndirectRef) Equals 

func (ir PDFIndirectRef) Equals(indRef PDFIndirectRef) bool

Equals returns true if two indirect References refer to the same object.

func (PDFIndirectRef) PDFString 

func (ir PDFIndirectRef) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFIndirectRef) String 

func (ir PDFIndirectRef) String() string

type PDFInteger 

type PDFInteger int

PDFInteger represents a PDF integer object.

func (PDFInteger) PDFString 

func (i PDFInteger) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFInteger) String 

func (i PDFInteger) String() string

func (PDFInteger) Value 

func (i PDFInteger) Value() int

Value returns an int value for this PDF object.

type PDFName 

type PDFName string

PDFName represents a PDF name object.

func (PDFName) PDFString 

func (nameObject PDFName) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFName) String 

func (nameObject PDFName) String() string

func (PDFName) Value 

func (nameObject PDFName) Value() string

Value returns a string value for this PDF object.

type PDFObject 

type PDFObject interface {
	fmt.Stringer
	PDFString() string
}

PDFObject defines an interface for all PDFObjects.

type PDFObjectStreamDict 

type PDFObjectStreamDict struct {
	PDFStreamDict
	Prolog         []byte
	ObjCount       int
	FirstObjOffset int
	ObjArray       PDFArray
}

PDFObjectStreamDict represents a object stream dictionary.

func NewPDFObjectStreamDict 

func NewPDFObjectStreamDict() *PDFObjectStreamDict

NewPDFObjectStreamDict creates a new PDFObjectStreamDict object.

func (*PDFObjectStreamDict) AddObject 

func (oStreamDict *PDFObjectStreamDict) AddObject(objNumber int, entry *XRefTableEntry) error

AddObject adds another object to this object stream. Relies on decoded content!

func (*PDFObjectStreamDict) Finalize 

func (oStreamDict *PDFObjectStreamDict) Finalize()

Finalize prepares the final content of the objectstream.

func (*PDFObjectStreamDict) IndexedObject 

func (oStreamDict *PDFObjectStreamDict) IndexedObject(index int) (PDFObject, error)

IndexedObject returns the object at given index from a PDFObjectStreamDict.

type PDFStats 

type PDFStats struct {
	// contains filtered or unexported fields
}

PDFStats is a container for stats.

func NewPDFStats 

func NewPDFStats() PDFStats

NewPDFStats returns a new PDFStats object.

func (PDFStats) AddPageAttr 

func (stats PDFStats) AddPageAttr(name int)

AddPageAttr adds the occurrence of a field with given name to the pageAttrs set.

func (PDFStats) AddRootAttr 

func (stats PDFStats) AddRootAttr(name int)

AddRootAttr adds the occurrence of a field with given name to the rootAttrs set.

func (PDFStats) UsesPageAttr 

func (stats PDFStats) UsesPageAttr(name int) bool

UsesPageAttr returns true if a field with given name is contained in the pageAttrs set.

func (PDFStats) UsesRootAttr 

func (stats PDFStats) UsesRootAttr(name int) bool

UsesRootAttr returns true if a field with given name is contained in the rootAttrs set.

type PDFStreamDict 

type PDFStreamDict struct {
	PDFDict
	StreamOffset      int64
	StreamLength      *int64
	StreamLengthObjNr *int
	FilterPipeline    []PDFFilter
	Raw               []byte // Encoded
	Content           []byte // Decoded
	IsPageContent     bool
}

PDFStreamDict represents a PDF stream dict object.

func NewPDFStreamDict 

func NewPDFStreamDict(pdfDict PDFDict, streamOffset int64, streamLength *int64, streamLengthObjNr *int,
	filterPipeline []PDFFilter) PDFStreamDict

NewPDFStreamDict creates a new PDFStreamDict for given PDFDict, stream offset and length.

func (PDFStreamDict) HasSoleFilterNamed 

func (streamDict PDFStreamDict) HasSoleFilterNamed(filterName string) bool

HasSoleFilterNamed returns true if there is exactly one filter defined for a stream dict.

type PDFStringLiteral 

type PDFStringLiteral string

PDFStringLiteral represents a PDF string literal object.

func DateStringLiteral 

func DateStringLiteral(t time.Time) PDFStringLiteral

DateStringLiteral returns a PDFStringLiteral for time.

func (PDFStringLiteral) PDFString 

func (stringliteral PDFStringLiteral) PDFString() string

PDFString returns a string representation as found in and written to a PDF file.

func (PDFStringLiteral) String 

func (stringliteral PDFStringLiteral) String() string

func (PDFStringLiteral) Value 

func (stringliteral PDFStringLiteral) Value() string

Value returns a string value for this PDF object.

type PDFVersion 

type PDFVersion int

PDFVersion is a type for the internal representation of PDF versions. 

const (
	V10 PDFVersion = iota
	V11
	V12
	V13
	V14
	V15
	V16
	V17
)

Constants for all PDF versions up to v1.7

func Version 

func Version(versionStr string) (PDFVersion, error)

Version returns the PDFVersion for a version string.

type PDFXRefStreamDict 

type PDFXRefStreamDict struct {
	PDFStreamDict
	Size           int
	Objects        []int
	W              [3]int
	PreviousOffset *int64
}

PDFXRefStreamDict represents a cross reference stream dictionary.

func NewPDFXRefStreamDict 

func NewPDFXRefStreamDict(ctx *PDFContext) *PDFXRefStreamDict

NewPDFXRefStreamDict creates a new PDFXRefStreamDict object.

type ReadContext 

type ReadContext struct {

	// The PDF-File which gets processed.
	FileName string
	File     *os.File
	FileSize int64

	BinaryTotalSize     int64 // total stream data
	BinaryImageSize     int64 // total image stream data
	BinaryFontSize      int64 // total font stream data (fontfiles)
	BinaryImageDuplSize int64 // total obsolet image stream data after optimization
	BinaryFontDuplSize  int64 // total obsolet font stream data after optimization

	Linearized bool // File is linearized.
	Hybrid     bool // File is a hybrid PDF file.

	UsingObjectStreams bool   // File is using object streams.
	ObjectStreams      IntSet // All object numbers of any object streams found which need to be decoded.

	UsingXRefStreams bool   // File is using xref streams.
	XRefStreams      IntSet // All object numbers of any xref streams found.
}

ReadContext represents the context for reading a PDF file.

func (*ReadContext) IsObjectStreamObject 

func (rc *ReadContext) IsObjectStreamObject(i int) bool

IsObjectStreamObject returns true if object i is a an object stream. All compressed objects are object streams.

func (*ReadContext) IsXRefStreamObject 

func (rc *ReadContext) IsXRefStreamObject(i int) bool

IsXRefStreamObject returns true if object #i is a an xref stream.

func (*ReadContext) LogStats 

func (rc *ReadContext) LogStats(optimized bool)

LogStats logs stats for read file.

func (*ReadContext) ObjectStreamsString 

func (rc *ReadContext) ObjectStreamsString() (int, string)

ObjectStreamsString returns a formatted string and the number of object stream objects.

func (*ReadContext) XRefStreamsString 

func (rc *ReadContext) XRefStreamsString() (int, string)

XRefStreamsString returns a formatted string and the number of xref stream objects.

type StringSet 

type StringSet map[string]bool

StringSet is a set of strings.

type WriteContext 

type WriteContext struct {

	// The PDF-File which gets generated.
	DirName  string
	FileName string
	FileSize int64
	*bufio.Writer

	Command       string // command in effect.
	ExtractPageNr int    // page to be generated for rendering a single-page/PDF.
	ExtractPages  IntSet // pages to be generated for a trimmed PDF.

	BinaryTotalSize int64 // total stream data, counts 100% all stream data written.
	BinaryImageSize int64 // total image stream data written = Read.BinaryImageSize.
	BinaryFontSize  int64 // total font stream data (fontfiles) = copy of Read.BinaryFontSize.

	Table  map[int]int64 // object write offsets
	Offset int64         // current write offset

	WriteToObjectStream bool // if true start to embed objects into object streams and obey ObjectStreamMaxObjects.
	CurrentObjStream    *int // if not nil, any new non-stream-object gets added to the object stream with this object number.

	Eol string // end of line char sequence
}

WriteContext represents the context for writing a PDF file.

func NewWriteContext 

func NewWriteContext(eol string) *WriteContext

NewWriteContext returns a new WriteContext.

func (*WriteContext) ExtractPage 

func (wc *WriteContext) ExtractPage(i int) bool

ExtractPage returns true if page i needs to be generated.

func (*WriteContext) HasWriteOffset 

func (wc *WriteContext) HasWriteOffset(objNumber int) bool

HasWriteOffset returns true if an object has already been written to PDFDestination.

func (*WriteContext) LogStats 

func (wc *WriteContext) LogStats()

LogStats logs stats for written file.

func (*WriteContext) ReducedFeatureSet 

func (wc *WriteContext) ReducedFeatureSet() bool

ReducedFeatureSet returns true for Split,Trim,Merge,ExtractPages. Don't confuse with pdfcpu commands, these are internal triggers.

func (*WriteContext) SetWriteOffset 

func (wc *WriteContext) SetWriteOffset(objNumber int)

SetWriteOffset saves the current write offset to the PDFDestination.

func (*WriteContext) WriteEol 

func (wc *WriteContext) WriteEol() error

WriteEol writes an end of line sequence.

type XRefTable 

type XRefTable struct {
	Table               map[int]*XRefTableEntry
	Size                *int             // Object count from PDF trailer dict.
	PageCount           int              // Number of pages, set during validation.
	Root                *PDFIndirectRef  // Pointer to catalog (reference to root object).
	RootDict            *PDFDict         // Catalog
	Names               map[string]*Node // Cache for name trees as found in catalog.
	Encrypt             *PDFIndirectRef  // Encrypt dict.
	E                   *Enc
	EncKey              []byte // Encrypt key.
	AES4Strings         bool
	AES4Streams         bool
	AES4EmbeddedStreams bool

	// PDF Version
	HeaderVersion *PDFVersion // The PDF version the source is claiming to us as per its header.
	RootVersion   *PDFVersion // Optional PDF version taking precedence over the header version.

	// Document information section
	Info     *PDFIndirectRef // Infodict (reference to info dict object)
	ID       *PDFArray       // from info dict (or trailer?)
	Author   string
	Creator  string
	Producer string

	// Linearization section (not yet supported)
	OffsetPrimaryHintTable  *int64
	OffsetOverflowHintTable *int64
	LinearizationObjs       IntSet

	// Offspec section
	AdditionalStreams *PDFArray // array of PDFIndirectRef - trailer :e.g., Oasis "Open Doc"

	// Statistics
	Stats PDFStats

	Tagged bool // File is using tags. This is important for ???

	// Validation
	Valid          bool // true means successful validated against ISO 32000.
	ValidationMode int  // see Configuration

	Optimized bool
}

XRefTable represents a PDF cross reference table plus stats for a PDF file.

func CreateAcroFormDemoXRef 

func CreateAcroFormDemoXRef() (*XRefTable, error)

CreateAcroFormDemoXRef creates a PDF file with an AcroForm example.

func CreateAnnotationDemoXRef 

func CreateAnnotationDemoXRef() (*XRefTable, error)

CreateAnnotationDemoXRef creates a PDF file with examples of annotations and actions.

func (*XRefTable) BindNameTrees 

func (xRefTable *XRefTable) BindNameTrees() error

BindNameTrees syncs up the internal name tree cache with the xreftable.

func (*XRefTable) Catalog 

func (xRefTable *XRefTable) Catalog() (*PDFDict, error)

Catalog returns a pointer to the root object / catalog.

func (*XRefTable) CatalogHasPieceInfo 

func (xRefTable *XRefTable) CatalogHasPieceInfo() (bool, error)

CatalogHasPieceInfo returns true if the root has an entry for \"PieceInfo\".

func (*XRefTable) DeleteObject 

func (xRefTable *XRefTable) DeleteObject(objectNumber int) error

DeleteObject marks an object as free and inserts it into the free list right after the head.

func (*XRefTable) DeleteObjectGraph 

func (xRefTable *XRefTable) DeleteObjectGraph(obj PDFObject) error

DeleteObjectGraph deletes all objects reachable by indRef.

func (*XRefTable) Dereference 

func (xRefTable *XRefTable) Dereference(obj PDFObject) (PDFObject, error)

Dereference resolves an indirect object and returns the resulting PDF object.

func (*XRefTable) DereferenceArray 

func (xRefTable *XRefTable) DereferenceArray(obj PDFObject) (*PDFArray, error)

DereferenceArray resolves and validates an array object, which may be an indirect reference.

func (*XRefTable) DereferenceDict 

func (xRefTable *XRefTable) DereferenceDict(obj PDFObject) (*PDFDict, error)

DereferenceDict resolves and validates a dictionary object, which may be an indirect reference.

func (*XRefTable) DereferenceInteger 

func (xRefTable *XRefTable) DereferenceInteger(obj PDFObject) (*PDFInteger, error)

DereferenceInteger resolves and validates an integer object, which may be an indirect reference.

func (*XRefTable) DereferenceName 

func (xRefTable *XRefTable) DereferenceName(obj PDFObject, sinceVersion PDFVersion, validate func(string) bool) (n PDFName, err error)

DereferenceName resolves and validates a name object, which may be an indirect reference.

func (*XRefTable) DereferenceStreamDict 

func (xRefTable *XRefTable) DereferenceStreamDict(obj PDFObject) (*PDFStreamDict, error)

DereferenceStreamDict resolves and validates a stream dictionary object, which may be an indirect reference.

func (*XRefTable) DereferenceStringLiteral 

func (xRefTable *XRefTable) DereferenceStringLiteral(obj PDFObject, sinceVersion PDFVersion, validate func(string) bool) (s PDFStringLiteral, err error)

DereferenceStringLiteral resolves and validates a string literal object, which may be an indirect reference.

func (*XRefTable) DereferenceStringOrHexLiteral 

func (xRefTable *XRefTable) DereferenceStringOrHexLiteral(obj PDFObject, sinceVersion PDFVersion, validate func(string) bool) (o PDFObject, err error)

DereferenceStringOrHexLiteral resolves and validates a string or hex literal object, which may be an indirect reference.

func (*XRefTable) EncryptDict 

func (xRefTable *XRefTable) EncryptDict() (*PDFDict, error)

EncryptDict returns a pointer to the root object / catalog.

func (*XRefTable) EnsureCollection 

func (xRefTable *XRefTable) EnsureCollection() error

EnsureCollection makes sure there is a Collection entry in the catalog. Needed for portfolio / portable collections eg. for file attachments.

func (*XRefTable) EnsureValidFreeList 

func (xRefTable *XRefTable) EnsureValidFreeList() error

EnsureValidFreeList ensures the integrity of the free list associated with the recorded free objects. See 7.5.4 Cross-Reference Table

func (*XRefTable) Exists 

func (xRefTable *XRefTable) Exists(objNumber int) bool

Exists returns true if xRefTable contains an entry for objNumber.

func (*XRefTable) Find 

func (xRefTable *XRefTable) Find(objNumber int) (*XRefTableEntry, bool)

Find returns the XRefTable entry for given object number.

func (*XRefTable) FindObject 

func (xRefTable *XRefTable) FindObject(objNumber int) (PDFObject, error)

FindObject returns the object of the XRefTableEntry for a specific object number.

func (*XRefTable) FindTableEntry 

func (xRefTable *XRefTable) FindTableEntry(objNumber int, generationNumber int) (*XRefTableEntry, bool)

FindTableEntry returns the XRefTable entry for given object and generation numbers.

func (*XRefTable) FindTableEntryForIndRef 

func (xRefTable *XRefTable) FindTableEntryForIndRef(indRef *PDFIndirectRef) (*XRefTableEntry, bool)

FindTableEntryForIndRef returns the XRefTable entry for given indirect reference.

func (*XRefTable) FindTableEntryLight 

func (xRefTable *XRefTable) FindTableEntryLight(objNumber int) (*XRefTableEntry, bool)

FindTableEntryLight returns the XRefTable entry for given object number.

func (*XRefTable) Free 

func (xRefTable *XRefTable) Free(objNumber int) (*XRefTableEntry, error)

Free returns the cross ref table entry for given number of a free object.

func (*XRefTable) IDFirstElement 

func (xRefTable *XRefTable) IDFirstElement() (id []byte, err error)

IDFirstElement returns the first element of ID.

func (*XRefTable) IndRefForNewObject 

func (xRefTable *XRefTable) IndRefForNewObject(obj PDFObject) (*PDFIndirectRef, error)

IndRefForNewObject inserts an object into the xRefTable and returns an indirect reference to it.

func (*XRefTable) InsertAndUseRecycled 

func (xRefTable *XRefTable) InsertAndUseRecycled(xRefTableEntry XRefTableEntry) (objNumber int, err error)

InsertAndUseRecycled adds given xRefTableEntry into the cross reference table utilizing the freelist.

func (*XRefTable) InsertNew 

func (xRefTable *XRefTable) InsertNew(xRefTableEntry XRefTableEntry) (objNumber int)

InsertNew adds given xRefTableEntry at next new objNumber into the cross reference table. Only to be called once an xRefTable has been generated completely and all trailer dicts have been processed. xRefTable.Size is the size entry of the first trailer dict processed. Called on creation of new object streams. Called by InsertAndUseRecycled.

func (*XRefTable) InsertObject 

func (xRefTable *XRefTable) InsertObject(obj PDFObject) (objNumber int, err error)

InsertObject inserts an object into the xRefTable.

func (*XRefTable) IsLinearizationObject 

func (xRefTable *XRefTable) IsLinearizationObject(i int) bool

IsLinearizationObject returns true if object #i is a a linearization object.

func (*XRefTable) LinearizationObjsString 

func (xRefTable *XRefTable) LinearizationObjsString() (int, string)

LinearizationObjsString returns a formatted string and the number of objs.

func (*XRefTable) LocateNameTree 

func (xRefTable *XRefTable) LocateNameTree(nameTreeName string, ensure bool) error

LocateNameTree locates/ensures a specific name tree.

func (*XRefTable) MissingObjects 

func (xRefTable *XRefTable) MissingObjects() (int, *string)

MissingObjects returns the number of objects that were not written plus the corresponding comma separated string representation.

func (*XRefTable) NamesDict 

func (xRefTable *XRefTable) NamesDict() (*PDFDict, error)

NamesDict returns the dict that contains all name trees.

func (*XRefTable) NewEmbeddedFileStreamDict 

func (xRefTable *XRefTable) NewEmbeddedFileStreamDict(filename string) (*PDFStreamDict, error)

NewEmbeddedFileStreamDict creates and returns an embeddedFileStreamDict containing the file "filename".

func (*XRefTable) NewFileSpecDict 

func (xRefTable *XRefTable) NewFileSpecDict(filename string, indRefStreamDict PDFIndirectRef) (*PDFDict, error)

NewFileSpecDict creates and returns a new fileSpec dictionary.

func (*XRefTable) NewPDFStreamDict 

func (xRefTable *XRefTable) NewPDFStreamDict(filename string) (*PDFStreamDict, error)

NewPDFStreamDict creates a streamDict for buf.

func (*XRefTable) NewSoundStreamDict 

func (xRefTable *XRefTable) NewSoundStreamDict(filename string, samplingRate int, fileSpecDict *PDFDict) (*PDFStreamDict, error)

NewSoundStreamDict returns a new sound stream dict.

func (*XRefTable) NextForFree 

func (xRefTable *XRefTable) NextForFree(objNumber int) (int, error)

NextForFree returns the number of the object the free object with objNumber links to. This is the successor of this free object in the free list.

func (*XRefTable) PageDict 

func (xRefTable *XRefTable) PageDict(page int) (*PDFDict, error)

PageDict returns a specific page dict.

func (*XRefTable) Pages 

func (xRefTable *XRefTable) Pages() (*PDFIndirectRef, error)

Pages returns the Pages reference contained in the catalog.

func (*XRefTable) ParseRootVersion 

func (xRefTable *XRefTable) ParseRootVersion() (v *string, err error)

ParseRootVersion returns a string representation for an optional Version entry in the root object.

func (*XRefTable) RemoveCollection 

func (xRefTable *XRefTable) RemoveCollection() error

RemoveCollection removes an existing Collection entry from the catalog.

func (*XRefTable) RemoveEmbeddedFilesNameTree 

func (xRefTable *XRefTable) RemoveEmbeddedFilesNameTree() error

RemoveEmbeddedFilesNameTree removes both the embedded files name tree and the Collection dict.

func (*XRefTable) RemoveNameTree 

func (xRefTable *XRefTable) RemoveNameTree(nameTreeName string) error

RemoveNameTree removes a specific name tree. Also removes a resulting empty names dict.

func (*XRefTable) UndeleteObject 

func (xRefTable *XRefTable) UndeleteObject(objectNumber int) error

UndeleteObject ensures an object is not recorded in the free list. e.g. sometimes caused by indirect references to free objects in the original PDF file.

func (*XRefTable) ValidateVersion 

func (xRefTable *XRefTable) ValidateVersion(element string, sinceVersion PDFVersion) error

ValidateVersion validates against the xRefTable's version.

func (*XRefTable) Version 

func (xRefTable *XRefTable) Version() PDFVersion

Version returns the PDF version of the PDF writer that created this file. Before V1.4 this is the header version. Since V1.4 the catalog may contain a Version entry which takes precedence over the header version.

func (*XRefTable) VersionString 

func (xRefTable *XRefTable) VersionString() string

VersionString return a string representation for this PDF files PDF version.

type XRefTableEntry 

type XRefTableEntry struct {
	Free            bool
	Offset          *int64
	Generation      *int
	Object          PDFObject
	Compressed      bool
	ObjectStream    *int
	ObjectStreamInd *int
}

XRefTableEntry represents an entry in the PDF cross reference table.

This may wrap a free object, a compressed object or any in use PDF object:

PDFDict, PDFStreamDict, PDFObjectStreamDict, PDFXRefStreamDict, PDFArray, PDFInteger, PDFFloat, PDFName, PDFStringLiteral, PDFHexLiteral, PDFBoolean

func NewFreeHeadXRefTableEntry 

func NewFreeHeadXRefTableEntry() *XRefTableEntry

NewFreeHeadXRefTableEntry returns the xref table entry for object 0 which is per definition the head of the free list (list of free objects).

func NewXRefTableEntryGen0 

func NewXRefTableEntryGen0(obj PDFObject) *XRefTableEntry

NewXRefTableEntryGen0 returns a cross reference table entry for an object with generation 0.

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