Class PdfDecoder

Decodes PDF tokens into PDF objects. Handles parsing of all PDF object types including dictionaries, arrays, streams, and xref tables.

Hierarchy (View Summary)

IncrementalParser<PdfToken, PdfObject>
- PdfDecoder

Index

Constructors

constructor

new PdfDecoder(
options?: { ignoreWhitespace?: boolean; maxBufferSizeBytes?: number },
): PdfDecoder
Creates a new PDF decoder.
Parameters
- Optionaloptions: { ignoreWhitespace?: boolean; maxBufferSizeBytes?: number }
  Configuration options
  - OptionalignoreWhitespace?: boolean
    If true, whitespace tokens are ignored
  - OptionalmaxBufferSizeBytes?: number
    Maximum buffer size before compaction (default: 10MB)
Returns PdfDecoder
Overrides IncrementalParser.constructor
- Defined in packages/pdf-lite/src/core/decoder.ts:67

Properties

`Protected`buffer

buffer: PdfToken[] = []

Buffer holding input items

`Protected`bufferIndex

bufferIndex: number = 0

Current position in the buffer

eof

eof: boolean = false

Whether end of file has been signaled

`Protected`inputOffset

inputOffset: number = 0

Current position in the input stream

`Protected`outputOffset

outputOffset: number = 0

Number of outputs generated

Methods

`Protected`atEof

atEof(): boolean
Checks if end of file has been reached and buffer is exhausted.

Returns boolean
True if no more input is available
Inherited from IncrementalParser.atEof
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:58

`Protected`bufferSize

bufferSize(): number
Returns number
- Defined in packages/pdf-lite/src/core/decoder.ts:441

`Protected`canCompact

canCompact(): boolean
Override to customize when to compact the buffer By default, compacts when more than 1000 items have been consumed

Returns boolean
boolean indicating whether to compact the buffer
Overrides IncrementalParser.canCompact
- Defined in packages/pdf-lite/src/core/decoder.ts:445

`Protected`compact

compact(): void
Compacts the buffer by removing consumed items

Returns void
Inherited from IncrementalParser.compact
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:170

`Protected`expect

expect<T extends PdfToken>(itemType: T | (new (...args: any[]) => T)): T
Consumes and validates the next item against an expected type or value.
Type Parameters
- T extends PdfToken
  The expected item type
Parameters
- itemType: T | (new (...args: any[]) => T)
  Constructor or value to match against
Returns T
The consumed item cast to the expected type

Throws
Error if the item doesn't match the expected type/value
Inherited from IncrementalParser.expect
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:132

feed

feed(...input: (PdfToken | PdfToken[])[]): void
Feeds input items into the parser buffer.
Parameters
- ...input: (PdfToken | PdfToken[])[]
  Input items to add to the buffer
Returns void
Inherited from IncrementalParser.feed
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:39

`Protected`next

next(): PdfToken
Consumes and returns the next item from the buffer.

Returns PdfToken
The next item

Throws
NoMoreTokensError if more input is needed and EOF not signaled

Throws
EofReachedError if at EOF and no more items available
Inherited from IncrementalParser.next
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:87

nextItems

nextItems(): Generator<PdfObject>
Generates parsed output items from the buffer. Handles backtracking when more input is needed.

Returns Generator<PdfObject>
A generator yielding parsed output items
Inherited from IncrementalParser.nextItems
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:193

`Protected`oneOf

oneOf(...fn: (() => PdfObject)[]): PdfObject
Tries multiple parsing functions and returns the first successful result. Automatically backtracks on failure.
Parameters
- ...fn: (() => PdfObject)[]
  Array of parsing functions to try
Returns PdfObject
The result from the first successful parsing function

Throws
NoMoreTokensError if any function needs more input

Throws
Error if all parsing functions fail
Inherited from IncrementalParser.oneOf
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:148

`Protected`parse

parse(): PdfObject
Abstract method to parse the next output item from the buffer. Subclasses must implement this to define parsing logic.

Returns PdfObject
The parsed output item
Overrides IncrementalParser.parse
- Defined in packages/pdf-lite/src/core/decoder.ts:451

`Protected`peek

peek(ahead?: number): PdfToken | null
Peeks at an item in the buffer without consuming it.
Parameters
- ahead: number = 0
  Number of positions to look ahead (default: 0)
Returns PdfToken | null
The item at the peek position, or null if at EOF

Throws
NoMoreTokensError if more input is needed and EOF not signaled
Inherited from IncrementalParser.peek
- Defined in packages/pdf-lite/src/core/incremental-parser.ts:69

Class PdfDecoder

Hierarchy (View Summary)

Index

Constructors

Properties

Methods

Constructors

constructor

Parameters

OptionalignoreWhitespace?: boolean

OptionalmaxBufferSizeBytes?: number

Returns PdfDecoder

Properties

Protectedbuffer

ProtectedbufferIndex

eof

ProtectedinputOffset

ProtectedoutputOffset

Methods

ProtectedatEof

Returns boolean

ProtectedbufferSize

Returns number

ProtectedcanCompact

Returns boolean

Protectedcompact

Returns void

Protectedexpect

Type Parameters

Parameters

Returns T

Throws

feed

Parameters

Returns void

Protectednext

Returns PdfToken

Throws

Throws

nextItems

Returns Generator<PdfObject>

ProtectedoneOf

Parameters

Returns PdfObject

Throws

Throws

Protectedparse

Returns PdfObject

Protectedpeek

Parameters

Returns PdfToken | null

Throws

Settings

On This Page

`Optional`ignoreWhitespace?: boolean

`Optional`maxBufferSizeBytes?: number

`Protected`buffer

`Protected`bufferIndex

`Protected`inputOffset

`Protected`outputOffset

`Protected`atEof

`Protected`bufferSize

`Protected`canCompact

`Protected`compact

`Protected`expect

`Protected`next

`Protected`oneOf

`Protected`parse

`Protected`peek