DcmRLEDecoder Class Reference

this class implements an RLE decompressor conforming to the DICOM standard. More...

List of all members.

Public Member Functions
	DcmRLEDecoder (size_t outputBufferSize)
	constructor
	~DcmRLEDecoder ()
	destructor
void	clear ()
	resets the decoder object to newly constructed state.
OFCondition	decompress (void *compressedData, size_t compressedSize)
size_t	size () const
	returns the number of bytes written to the output buffer
void *	getOutputBuffer () const
	returns pointer to the output buffer
OFBool	fail () const
	returns true if the RLE compressor has failed (out of memory or output buffer too small).
Private Member Functions
	DcmRLEDecoder (const DcmRLEDecoder &)
	private undefined copy constructor
DcmRLEDecoder &	operator= (const DcmRLEDecoder &)
	private undefined copy assignment operator
void	replicate (unsigned char ch, unsigned char nbytes)
	this method expands a replicate run
void	literal (unsigned char *cp, unsigned char nbytes)
	this method expands a literal run
Private Attributes
int	fail_
	this flag indicates a failure of the RLE codec.
size_t	outputBufferSize_
	size of output buffer, in bytes
unsigned char *	outputBuffer_
	this member points to a block of size outputBufferSize_ (unless fail_ is true).
size_t	offset_
	contains the number of bytes already written to outputBuffer_.
unsigned char	suspendInfo_
	contains suspension information.

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Detailed Description

this class implements an RLE decompressor conforming to the DICOM standard.

The class is loosely based on an implementation by Phil Norman <forrey@eh.org>

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Constructor & Destructor Documentation

DcmRLEDecoder::DcmRLEDecoder

(

size_t

outputBufferSize

)

[inline]

constructor

Parameters:

outputBufferSize

size of the output buffer (in bytes) to which the RLE codec will write decompressed output.

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Member Function Documentation

void DcmRLEDecoder::clear

(

)

[inline]

resets the decoder object to newly constructed state.

The size and location of the output buffer is not changed.

void DcmRLEDecoder::literal	(	unsigned char *	cp,
		unsigned char	nbytes
	)		[inline, private]

this method expands a literal run

Parameters:

cp	pointer to buffer
nbytes	number of bytes in buffer

void DcmRLEDecoder::replicate	(	unsigned char	ch,
		unsigned char	nbytes
	)		[inline, private]

this method expands a replicate run

Parameters:

ch	value to replicate
nbytes	number of repetitions

size_t DcmRLEDecoder::size

(

)

const [inline]

returns the number of bytes written to the output buffer

Returns:

size of decompressed stream, in bytes

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Member Data Documentation

int DcmRLEDecoder::fail_ [private]

this flag indicates a failure of the RLE codec.

Once a failure is flagged, the codec will consume all input and not produce any more output.

size_t DcmRLEDecoder::offset_ [private]

contains the number of bytes already written to outputBuffer_.

Value is always less or equal to outputBufferSize_.

unsigned char* DcmRLEDecoder::outputBuffer_ [private]

this member points to a block of size outputBufferSize_ (unless fail_ is true).

This is the block of data to which the decompressed stream is written

unsigned char DcmRLEDecoder::suspendInfo_ [private]

contains suspension information.

If not suspended, contains 128. If suspended during a replicate run, contains control byte of repeat run (> 128). If suspended during a literal run, contains number of remaining bytes in literal run minus 1 (< 128).

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The documentation for this class was generated from the following file:

• dcmdata/include/dcmtk/dcmdata/dcrledec.h