Represents a instance of a PNG chunk More...

Inherited by Hjg.Pngcs.Chunks.PngChunkMultiple, Hjg.Pngcs.Chunks.PngChunkSingle, and Hjg.Pngcs.Chunks.PngChunkSkipped.

Public Types
enum	ChunkOrderingConstraint { NONE, BEFORE_PLTE_AND_IDAT, AFTER_PLTE_BEFORE_IDAT, BEFORE_IDAT, NA }
	Restrictions for chunk ordering, for ancillary chunks More...

Public Member Functions
ChunkRaw	createEmptyChunk (int len, bool alloc)

override String	ToString ()
	Basic info: Id, length, Type name

abstract ChunkRaw	CreateRawChunk ()
	Serialization. Creates a Raw chunk, ready for write, from this chunk content

abstract void	ParseFromRaw (ChunkRaw c)
	Deserialization. Given a Raw chunk, just rad, fills this chunk content

abstract void	CloneDataFromRead (PngChunk other)
	Override to make a copy (normally deep) from other chunk

abstract bool	AllowsMultiple ()
	This is implemented in PngChunkMultiple/PngChunSingle

abstract ChunkOrderingConstraint	GetOrderingConstraint ()
	Get ordering constrain

Static Public Member Functions
static void	FactoryRegister (String chunkId, Type type)
	Registers a Chunk ID in the factory, to instantiate a given type

static T	CloneChunk< T > (T chunk, ImageInfo info)

Public Attributes
readonly String	Id
	4 letters. The Id almost determines the concrete type (except for PngUKNOWN)

readonly bool	Crit
	Standard basic properties, implicit in the Id

Protected Member Functions
	PngChunk (String id, ImageInfo imgInfo)
	Constructs an empty chunk

Protected Attributes
readonly ImageInfo	ImgInfo
	Image basic info, mostly for some checks

Properties
bool	Priority `[get, set]`
	For writing. Queued chunks with high priority will be written as soon as possible

int	ChunkGroup `[get, set]`
	Chunk group where it was read or writen

int	Length `[get, set]`

long	Offset `[get, set]`

Detailed Description

Represents a instance of a PNG chunk

Concrete classes should extend PngChunkSingle or PngChunkMultiple

Note that some methods/fields are type-specific (GetOrderingConstraint(), AllowsMultiple()) some are 'almost' type-specific (Id,Crit,Pub,Safe; the exception is PngUKNOWN), and some are instance-specific

Ref: http://www.libpng.org/pub/png/spec/1.2/PNG-Chunks.html

Member Enumeration Documentation

enum Hjg.Pngcs.Chunks.PngChunk.ChunkOrderingConstraint

Restrictions for chunk ordering, for ancillary chunks

Enumerator:

NONE	No constraint, the chunk can go anywhere
BEFORE_PLTE_AND_IDAT	Before PLTE (palette) - and hence, also before IDAT
AFTER_PLTE_BEFORE_IDAT	After PLTE (palette), but before IDAT
BEFORE_IDAT	Before IDAT (before or after PLTE)
NA	Does not apply

Constructor & Destructor Documentation

Hjg.Pngcs.Chunks.PngChunk.PngChunk	(	String	id,
		ImageInfo	imgInfo
	)

protected

Constructs an empty chunk

Parameters

id
imgInfo

Member Function Documentation

static void Hjg.Pngcs.Chunks.PngChunk.FactoryRegister	(	String	chunkId,
		Type	type
	)

static

Registers a Chunk ID in the factory, to instantiate a given type

This can be called by client code to register additional chunk types

Parameters

chunkId
type	should extend PngChunkSingle or PngChunkMultiple

ChunkRaw Hjg.Pngcs.Chunks.PngChunk.createEmptyChunk	(	int	len,
		bool	alloc
	)

static T Hjg.Pngcs.Chunks.PngChunk.CloneChunk< T >	(	T	chunk,
		ImageInfo	info
	)

static

Type Constraints

T

:

PngChunk

override String Hjg.Pngcs.Chunks.PngChunk.ToString ( )

Basic info: Id, length, Type name

Returns

abstract ChunkRaw Hjg.Pngcs.Chunks.PngChunk.CreateRawChunk ( )

pure virtual

abstract void Hjg.Pngcs.Chunks.PngChunk.ParseFromRaw ( ChunkRaw c )

pure virtual

abstract void Hjg.Pngcs.Chunks.PngChunk.CloneDataFromRead ( PngChunk other )

pure virtual

abstract bool Hjg.Pngcs.Chunks.PngChunk.AllowsMultiple ( )

pure virtual

This is implemented in PngChunkMultiple/PngChunSingle

Returns: Allows more than one chunk of this type in a image

Implemented in Hjg.Pngcs.Chunks.PngChunkMultiple, Hjg.Pngcs.Chunks.PngChunkSingle, and Hjg.Pngcs.Chunks.PngChunkSkipped.

abstract ChunkOrderingConstraint Hjg.Pngcs.Chunks.PngChunk.GetOrderingConstraint ( )

pure virtual

Member Data Documentation

readonly String Hjg.Pngcs.Chunks.PngChunk.Id

4 letters. The Id almost determines the concrete type (except for PngUKNOWN)

readonly bool Hjg.Pngcs.Chunks.PngChunk.Crit

Standard basic properties, implicit in the Id

readonly ImageInfo Hjg.Pngcs.Chunks.PngChunk.ImgInfo

protected

Image basic info, mostly for some checks

Property Documentation

bool Hjg.Pngcs.Chunks.PngChunk.Priority

getset

For writing. Queued chunks with high priority will be written as soon as possible

int Hjg.Pngcs.Chunks.PngChunk.ChunkGroup

getset

Chunk group where it was read or writen

int Hjg.Pngcs.Chunks.PngChunk.Length

getset

long Hjg.Pngcs.Chunks.PngChunk.Offset

getset

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Properties

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

Property Documentation