C# Class Hjg.Pngcs.PngWriter

Writes a PNG image, line by line.

Show file Open project: devedse/DeveMazeGenerator Class Usage Examples

Public Properties

Property	Type	Description
ImgInfo	Hjg.Pngcs.ImageInfo

Protected Properties

Property	Type	Description
filename	String
rowb	byte[]
rowbfilter	byte[]
rowbprev	byte[]

Public Methods

Method	Description
ComputeCompressionRatio ( ) : double	Computes compressed size/raw size, approximate Actually: compressed size = total size of IDAT data , raw size = uncompressed pixel bytes = rows * (bytesPerRow + 1)
CopyChunksFirst ( PngReader reader, int copy_mask ) : void
CopyChunksLast ( PngReader reader, int copy_mask ) : void
End ( ) : void	Finalizes the image creation and closes the file stream. This MUST be called after writing the lines.
GetChunksList ( ) : ChunksListForWrite
GetFilename ( ) : String	Filename or description, from the optional constructor argument.
GetMetadata ( ) : PngMetadata
IsUnpackedMode ( ) : bool
PngWriter ( Stream outputStream, Hjg.Pngcs.ImageInfo imgInfo ) : System	Constructs a PngWriter from a outputStream, with no filename information
PngWriter ( Stream outputStream, Hjg.Pngcs.ImageInfo imgInfo, String filename ) : System	Constructs a PngWriter from a outputStream, with optional filename or description After construction nothing is writen yet. You still can set some parameters (compression, filters) and queue chunks before start writing the pixels. See also `FileHelper.createPngWriter()`
SetFilterType ( FilterType filterType ) : void	Sets internal prediction filter type, or strategy to choose it. This must be called just after constructor, before starting writing. Recommended values: DEFAULT (default) or AGGRESIVE
SetUseUnPackedMode ( bool useUnpackedMode ) : void
WriteRow ( Hjg.Pngcs.ImageLine imgline, int rownumber ) : void	this uses the row number from the imageline!
WriteRow ( int newrow ) : void
WriteRow ( int newrow, int rown ) : void
WriteRowByte ( byte newrow, int rown ) : void
WriteRowInt ( int newrow, int rown ) : void	Writes a full image row. This must be called sequentially from n=0 to n=rows-1 One integer per sample , in the natural order: R G B R G B ... (or R G B A R G B A... if has alpha) The values should be between 0 and 255 for 8 bitspc images, and between 0- 65535 form 16 bitspc images (this applies also to the alpha channel if present) The array can be reused.
WriteRowsByte ( byte image ) : void
WriteRowsInt ( int image ) : void

Protected Methods

Method	Description
encodeRowFromByte ( byte row ) : void
encodeRowFromInt ( int row ) : void

Private Methods

Method	Description
CopyChunks ( PngReader reader, int copy_mask, bool onlyAfterIdat ) : void	copy chunks from reader - copy_mask : see ChunksToWrite.COPY_XXX If we are after idat, only considers those chunks after IDAT in PngReader TODO: this should be more customizable
FilterRow ( int rown ) : void
FilterRowAverage ( ) : void
FilterRowNone ( ) : void
FilterRowPaeth ( ) : void
FilterRowSub ( ) : void
FilterRowUp ( ) : void
SumRowbfilter ( ) : long
WriteEndChunk ( ) : void
WriteFirstChunks ( ) : void
WriteLastChunks ( ) : void
WriteSignatureAndIHDR ( ) : void	Write id signature and also "IHDR" chunk
filterAndSend ( int rown ) : void
init ( ) : void	init: is called automatically before writing the first row
prepareEncodeRow ( int rown ) : void
reportResultsForFilter ( int rown, FilterType type, bool tentative ) : void

Method Details

ComputeCompressionRatio() public method

Computes compressed size/raw size, approximate

Actually: compressed size = total size of IDAT data , raw size = uncompressed pixel bytes = rows * (bytesPerRow + 1)

public ComputeCompressionRatio ( ) : double
return	double

CopyChunksFirst() public method

public CopyChunksFirst ( PngReader reader, int copy_mask ) : void
reader	PngReader
copy_mask	int
return	void

CopyChunksLast() public method

public CopyChunksLast ( PngReader reader, int copy_mask ) : void
reader	PngReader
copy_mask	int
return	void

End() public method

Finalizes the image creation and closes the file stream.

This MUST be called after writing the lines.

public End ( ) : void
return	void

GetChunksList() public method

public GetChunksList ( ) : ChunksListForWrite
return	ChunksListForWrite

GetFilename() public method

Filename or description, from the optional constructor argument.

public GetFilename ( ) : String
return	String

GetMetadata() public method

public GetMetadata ( ) : PngMetadata
return	PngMetadata

IsUnpackedMode() public method

public IsUnpackedMode ( ) : bool
return	bool

PngWriter() public method

Constructs a PngWriter from a outputStream, with no filename information

public PngWriter ( Stream outputStream, Hjg.Pngcs.ImageInfo imgInfo ) : System
outputStream	Stream
imgInfo	Hjg.Pngcs.ImageInfo
return	System

PngWriter() public method

Constructs a PngWriter from a outputStream, with optional filename or description

After construction nothing is writen yet. You still can set some parameters (compression, filters) and queue chunks before start writing the pixels. See also FileHelper.createPngWriter()

public PngWriter ( Stream outputStream, Hjg.Pngcs.ImageInfo imgInfo, String filename ) : System
outputStream	Stream	Opened stream for binary writing
imgInfo	Hjg.Pngcs.ImageInfo	Basic image parameters
filename	String	Optional, can be the filename or a description.
return	System

SetFilterType() public method

Sets internal prediction filter type, or strategy to choose it.

This must be called just after constructor, before starting writing. Recommended values: DEFAULT (default) or AGGRESIVE

public SetFilterType ( FilterType filterType ) : void
filterType	FilterType	One of the five prediction types or strategy to choose it
return	void

SetUseUnPackedMode() public method

public SetUseUnPackedMode ( bool useUnpackedMode ) : void
useUnpackedMode	bool
return	void

WriteRow() public method

this uses the row number from the imageline!

public WriteRow ( Hjg.Pngcs.ImageLine imgline, int rownumber ) : void
imgline	Hjg.Pngcs.ImageLine
rownumber	int
return	void

WriteRow() public method

public WriteRow ( int newrow ) : void
newrow	int
return	void

WriteRow() public method

public WriteRow ( int newrow, int rown ) : void
newrow	int
rown	int
return	void

WriteRowByte() public method

public WriteRowByte ( byte newrow, int rown ) : void
newrow	byte
rown	int
return	void

WriteRowInt() public method

Writes a full image row.

This must be called sequentially from n=0 to n=rows-1 One integer per sample , in the natural order: R G B R G B ... (or R G B A R G B A... if has alpha) The values should be between 0 and 255 for 8 bitspc images, and between 0- 65535 form 16 bitspc images (this applies also to the alpha channel if present) The array can be reused.

public WriteRowInt ( int newrow, int rown ) : void
newrow	int	Array of pixel values
rown	int	Number of row, from 0 (top) to rows-1 (bottom)
return	void

WriteRowsByte() public method

public WriteRowsByte ( byte image ) : void
image	byte
return	void

WriteRowsInt() public method

public WriteRowsInt ( int image ) : void
image	int
return	void

encodeRowFromByte() protected method

protected encodeRowFromByte ( byte row ) : void
row	byte
return	void

encodeRowFromInt() protected method

protected encodeRowFromInt ( int row ) : void
row	int
return	void

Property Details

ImgInfo public property

Basic image info, inmutable

public ImageInfo,Hjg.Pngcs ImgInfo
return	Hjg.Pngcs.ImageInfo

filename protected property

filename, or description - merely informative, can be empty

protected String filename
return	String

rowb protected property

raw current row, as array of bytes,counting from 1 (index 0 is reserved for filter type)

protected byte[] rowb
return	byte[]

rowbfilter protected property

raw current row, after filtered

protected byte[] rowbfilter
return	byte[]

rowbprev protected property

previuos raw row

protected byte[] rowbprev
return	byte[]