This is a I2DImgSource implementation that can parse JPEG files and convert them into DICOM images. More...

Inheritance diagram for I2DJpegSource:

Public Member Functions
	I2DJpegSource ()
	Constructor, initializes member variables. More...

OFString	inputFormat () const
	Returns format of input image. More...

OFCondition	readPixelData (Uint16 &rows, Uint16 &cols, Uint16 &samplesPerPixel, OFString &photoMetrInt, Uint16 &bitsAlloc, Uint16 &bitsStored, Uint16 &highBit, Uint16 &pixelRepr, Uint16 &planConf, Uint16 &pixAspectH, Uint16 &pixAspectV, char *&pixData, Uint32 &length, E_TransferSyntax &ts)
	Extracts the raw JPEG pixel data stream from a JPEG file and returns some further information about this pixel data. More...

OFCondition	getLossyComprInfo (OFBool &srcEncodingLossy, OFString &srcLossyComprMethod) const
	After reading of pixel data, this function can be used for getting information about lossy compression parameters. More...

void	setExtSeqSupport (const OFBool enabled)
	Enable/Disable support for Extended Sequential JPEG Coding. More...

void	setProgrSupport (const OFBool enabled)
	Enable/Disable support for Progressive JPEG Coding. More...

void	setInsistOnJFIF (const OFBool enabled)
	If enabled, conversion will only take place if JFIF data could be found and evaluated. More...

void	setKeepAPPn (const OFBool enabled)
	If enabled, APPn markers (except JFIF!) are also copied to the output file. More...

	~I2DJpegSource ()
	Destructor, frees some memory. More...

Public Member Functions inherited from I2DImgSource
	I2DImgSource ()
	Constructor.

void	setImageFile (const OFString &filename)
	Sets the input image file to read. More...

OFString	getImageFile ()
	Returns the input image file that currently associated with plugin. More...

virtual	~I2DImgSource ()
	Virtual Destructor.

Static Public Member Functions
static OFString	jpegMarkerToString (const E_JPGMARKER &marker)
	Returns a string representation of a JPEG marker code. More...

Protected Member Functions
OFCondition	openFile (const OFString &filename)
	Opens the JPEG file specified by the given filename. More...

void	closeFile ()
	Closes JPEG file. More...

OFCondition	createJPEGFileMap ()
	Function that scans a JPEG file and creates a "file map" which includes all JPEG markers and their byte positions in the file. More...

void	debugDumpJPEGFileMap () const
	Dump the internal JPEG file map to a given stream. More...

OFCondition	getSOFImageParameters (const JPEGFileMapEntry &entry, Uint16 &imageWidth, Uint16 &imageHeight, Uint16 &samplesPerPixel, Uint16 &bitsPerSample)
	Get image parameters as found at given SOF marker of the JPEG image. More...

OFCondition	getJFIFImageParameters (const JPEGFileMapEntry &entry, Uint16 &jfifVersion, Uint16 &pixelAspectH, Uint16 &pixelAspectV, Uint16 &unit)
	Get JPEG parameters as found at given JFIF marker of the JPEG image. More...

OFCondition	isJPEGEncodingSupported (const E_JPGMARKER &jpegEncoding) const
	Check, whether a given JPEG image marker (SOFn) is supported by this plugin. More...

OFCondition	extractRawJPEGStream (char *&pixelData, Uint32 &pixLength)
	Extract raw JPEG stream (i.e. More...

OFCondition	copyJPEGStream (char *&pixelData, Uint32 &pixLength)
	Copies JPEG stream (with APPn markers, excluding JFIF) from JPEG file. More...

OFCondition	skipVariable ()
	Skips one marker while scanning through the JPEG file stream. More...

OFCondition	firstMarker (E_JPGMARKER &result)
	Tries to read the SOI marker. More...

OFCondition	nextMarker (const OFBool &lastWasSOSMarker, E_JPGMARKER &result)
	Tries to find the next JPEG marker in underlying file stream. More...

int	read2Bytes (Uint16 &result)
	Read 2 bytes from the byte stream. More...

int	read1Byte (Uint8 &result)
	Read 1 byte from the byte stream. More...

void	clearMap ()
	Deletes internal JPEG file map and frees memory. More...

Static Protected Member Functions
static E_TransferSyntax	associatedTS (const E_JPGMARKER &jpegEncoding)
	Returns if possible the DICOM transfer syntax matching the coding of the JPEG data. More...

static OFBool	isRSTMarker (const E_JPGMARKER &jpegEncoding)
	Returns true if marker is one of the RST0 to RST7 markers. More...

static OFBool	isSOFMarker (const E_JPGMARKER &jpegEncoding)
	Returns true if marker is one of the SOF0 to SOF15 markers. More...

Protected Attributes
OFList< JPEGFileMapEntry * >	m_jpegFileMap
	JPEG file map. More...

OFFile	jpegFile
	The JPEG file, if opened.

OFBool	m_disableProgrTs
	If true, JPEGs with progressive coding are not supported.

OFBool	m_disableExtSeqTs
	If true, JPEGs with extended sequential coding are not supported.

OFBool	m_insistOnJFIF
	If true, conversion will only work if JFIF header can be found. More...

OFBool	m_keepAPPn
	If true, APPn markers (except JFIF!) are also copied to the output file. More...

OFBool	m_lossyCompressed
	After reading pixel data, this denotes whether the source data is already lossy compressed.

Protected Attributes inherited from I2DImgSource
OFString	m_imageFile
	The input file.

Detailed Description

This is a I2DImgSource implementation that can parse JPEG files and convert them into DICOM images.

Constructor & Destructor Documentation

I2DJpegSource::I2DJpegSource ( )

Constructor, initializes member variables.

Returns: none

I2DJpegSource::~I2DJpegSource ( )

Destructor, frees some memory.

Returns: none

Member Function Documentation

static E_TransferSyntax I2DJpegSource::associatedTS ( const E_JPGMARKER & jpegEncoding )

staticprotected

Returns if possible the DICOM transfer syntax matching the coding of the JPEG data.

Parameters

jpegEncoding - [in] Image marker that should be tested

Returns: EC_Normal, marker is supported, error otherwise

void I2DJpegSource::clearMap ( )

protected

Deletes internal JPEG file map and frees memory.

Returns: none

void I2DJpegSource::closeFile ( )

protected

Closes JPEG file.

Returns: A string representation of the marker

OFCondition I2DJpegSource::copyJPEGStream	(	char *&	pixelData,
		Uint32 &	pixLength
	)

protected

Copies JPEG stream (with APPn markers, excluding JFIF) from JPEG file.

Parameters

pixelData	- [out] The resulting JPEG stream
pixLength	- [out] The length of the resulting stream

Returns: EC_Normal, if successful, error otherwise

OFCondition I2DJpegSource::createJPEGFileMap ( )

protected

Function that scans a JPEG file and creates a "file map" which includes all JPEG markers and their byte positions in the file.

Returns: EC_Normal, if successful, error otherwise

void I2DJpegSource::debugDumpJPEGFileMap ( ) const

protected

Dump the internal JPEG file map to a given stream.

The file map lists JPEG markers and their position in the bitstream found in the JPEG file

Returns: none

OFCondition I2DJpegSource::extractRawJPEGStream	(	char *&	pixelData,
		Uint32 &	pixLength
	)

protected

Extract raw JPEG stream (i.e.

without APPn markers) from JPEG file.

Parameters

pixelData	- [out] The resulting JPEG stream
pixLength	- [out] The length of the resulting stream

Returns: EC_Normal, if successful, error otherwise

OFCondition I2DJpegSource::firstMarker ( E_JPGMARKER & result )

protected

Tries to read the SOI marker.

Parameters

result - [out] The code of the SOI marker if successful (0xD8)

Returns: EC_Normal, if successful, error otherwise

OFCondition I2DJpegSource::getJFIFImageParameters	(	const JPEGFileMapEntry &	entry,
		Uint16 &	jfifVersion,
		Uint16 &	pixelAspectH,
		Uint16 &	pixelAspectV,
		Uint16 &	unit
	)

protected

Get JPEG parameters as found at given JFIF marker of the JPEG image.

Parameters

entry	- [in] This specifies the marker and the byte position of the JFIF marker
jfifVersion	- [out] The JFIF version of the JFIF data
pixelAspectH	- [out] The horizontal pixel aspect ratio
pixelAspectV	- [out] The vertical pixel aspect ratio
unit	- [out] The contents of the pixel aspect ratio unit field

Returns: EC_Normal, if successful, error otherwise

OFCondition I2DJpegSource::getLossyComprInfo	(	OFBool &	srcEncodingLossy,
		OFString &	srcLossyComprMethod
	)		const

virtual

After reading of pixel data, this function can be used for getting information about lossy compression parameters.

Parameters

srcEncodingLossy	- [out] Denotes, whether the encoding of the pixel data read was lossy (OFTrue) or lossless (OFFalse)
srcLossyComprMethod	- [out] Denotes the lossy compression method used in source if there is one (srcEncodingLossy = OFTrue). Should use defined terms of attribute Lossy Compression Method.

Returns: EC_Normal if information is available, error otherwise

Implements I2DImgSource.

OFCondition I2DJpegSource::getSOFImageParameters	(	const JPEGFileMapEntry &	entry,
		Uint16 &	imageWidth,
		Uint16 &	imageHeight,
		Uint16 &	samplesPerPixel,
		Uint16 &	bitsPerSample
	)

protected

Get image parameters as found at given SOF marker of the JPEG image.

Parameters

entry	- [in] This specifies the marker and the byte position of the SOF marker
imageWidth	- [out] The width of the image
imageHeight	- [out] The height of the image
samplesPerPixel	- [out] Number of components per pixel
bitsPerSample	- [out] Number of bits per pixel component

Returns: EC_Normal, if successful, error otherwise

OFString I2DJpegSource::inputFormat ( ) const

virtual

Returns format of input image.

For this class "JPEG" is returned.

Returns: Returns format of input image, i.e. "JPEG".

Implements I2DImgSource.

OFCondition I2DJpegSource::isJPEGEncodingSupported ( const E_JPGMARKER & jpegEncoding ) const

protected

Check, whether a given JPEG image marker (SOFn) is supported by this plugin.

Parameters

jpegEncoding - [in] Image marker that should be tested

Returns: EC_Normal, marker is supported, error otherwise

static OFBool I2DJpegSource::isRSTMarker ( const E_JPGMARKER & jpegEncoding )

staticprotected

Returns true if marker is one of the RST0 to RST7 markers.

Parameters

jpegEncoding - [in] Image marker that should be tested

Returns: OFTrue, if marker is RST0 to RST7, OFFalse otherwise

static OFBool I2DJpegSource::isSOFMarker ( const E_JPGMARKER & jpegEncoding )

staticprotected

Returns true if marker is one of the SOF0 to SOF15 markers.

Parameters

jpegEncoding - [in] Image marker that should be tested

Returns: OFTrue, if marker is SOF0 to SOF15, OFFalse otherwise

static OFString I2DJpegSource::jpegMarkerToString ( const E_JPGMARKER & marker )

static

Returns a string representation of a JPEG marker code.

Parameters

marker - [in] The marker to be converted

Returns: A string representation of the marker

OFCondition I2DJpegSource::nextMarker	(	const OFBool &	lastWasSOSMarker,
		E_JPGMARKER &	result
	)

protected

Tries to find the next JPEG marker in underlying file stream.

Parameters

lastWasSOSMarker	- [in] Denotes, whether the last marker read before was the SOS (start of scan) marker. This is needed to ignore non-marker 0xFF occurrences in the compressed data.
result	- [out] The result marker

Returns: EC_Normal, if successful, error otherwise

OFCondition I2DJpegSource::openFile ( const OFString & filename )

protected

Opens the JPEG file specified by the given filename.

Parameters

filename - [in] The file to be opened

Returns: EC_Normal, if successful, error otherwise

int I2DJpegSource::read1Byte ( Uint8 & result )

inlineprotected

Read 1 byte from the byte stream.

Parameters

result - [out] The result

Returns: 0, if successful, EOF if rest of stream does not contain enough bytes

int I2DJpegSource::read2Bytes ( Uint16 & result )

inlineprotected

Read 2 bytes from the byte stream.

Parameters

result - [out] The result

Returns: 0, if successful, EOF if rest of stream does not contain enough bytes

OFCondition I2DJpegSource::readPixelData	(	Uint16 &	rows,
		Uint16 &	cols,
		Uint16 &	samplesPerPixel,
		OFString &	photoMetrInt,
		Uint16 &	bitsAlloc,
		Uint16 &	bitsStored,
		Uint16 &	highBit,
		Uint16 &	pixelRepr,
		Uint16 &	planConf,
		Uint16 &	pixAspectH,
		Uint16 &	pixAspectV,
		char *&	pixData,
		Uint32 &	length,
		E_TransferSyntax &	ts
	)

virtual

Extracts the raw JPEG pixel data stream from a JPEG file and returns some further information about this pixel data.

Raw means here that all APP markers (e.g. JFIF information) are removed from the JPEG stream. The pixel data returned is a JPEG stream in JPEG interchange format. This function allocates memory for the pixel data returned to the user. The caller of this function is responsible for deleting the memory buffer.

Parameters

rows	- [out] Rows of image
cols	- [out] Columns of image
samplesPerPixel	- [out] Number of components per pixel
photoMetrInt	- [out] The DICOM color model used for the compressed data
bitsAlloc	- [out] Bits Allocated for one sample
bitsStored	- [out] Bits Stored, Number of bits actually stored within Bits Allocated
highBit	- [out] High Bit, Highest stored in bit within Bits Allocated
pixelRepr	- [out] Pixel Representation (0=unsigned, 1=signed)
planConf	- [out] Planar Configuration
pixAspectH	- [out] Horizontal value of pixel aspect ratio
pixAspectV	- [out] Vertical value of pixel aspect ratio
pixData	- [out] Pointer to the pixel data in JPEG Interchange Format (but without APPx markers).
length	- [out] Length of pixel data
ts	- [out] The transfer syntax imposed by the imported pixel pixel data. This is necessary for the JPEG importer that needs to report which TS must be used for the imported JPEG data (ie. baseline, progressive, ...).

Returns: EC_Normal, if successful, error otherwise

Implements I2DImgSource.

void I2DJpegSource::setExtSeqSupport ( const OFBool enabled )

Enable/Disable support for Extended Sequential JPEG Coding.

Parameters

enabled - [in] OFTrue: support Extended Sequential, OFFalse: do not support

Returns: none

void I2DJpegSource::setInsistOnJFIF ( const OFBool enabled )

If enabled, conversion will only take place if JFIF data could be found and evaluated.

Many digital cameras do not provide a JFIF header, so this is disabled by default.

void I2DJpegSource::setKeepAPPn ( const OFBool enabled )

If enabled, APPn markers (except JFIF!) are also copied to the output file.

This can cause a huge speedup because instead of parsing the whole JPEG file (for finding any APPn markers) the parsing stops after finding the SOFn marker (which is relevant for extracting width/height and so on. Default: false

Parameters

enabled - [in] OFTrue: copy APPn, OFFalse: cut off APPn info

Returns: none

void I2DJpegSource::setProgrSupport ( const OFBool enabled )

Enable/Disable support for Progressive JPEG Coding.

Parameters

enabled - [in] OFTrue: support Extended Sequential, OFFalse: do not support

Returns: none

OFCondition I2DJpegSource::skipVariable ( )

protected

Skips one marker while scanning through the JPEG file stream.

Returns: EC_Normal, if successful, error otherwise

Member Data Documentation

OFBool I2DJpegSource::m_insistOnJFIF

protected

If true, conversion will only work if JFIF header can be found.

Default: false

OFList<JPEGFileMapEntry*> I2DJpegSource::m_jpegFileMap

protected

JPEG file map.

This map includes all JPEG markers and their byte positions in the JPEG file.

OFBool I2DJpegSource::m_keepAPPn

protected

If true, APPn markers (except JFIF!) are also copied to the output file.

This can cause a huge speedup because instead of parsing the whole JPEG file (for finding any APPn markers) the parsing stops after finding the SOFn marker (which is relevant for extracting width/height and so on. Default: false

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

dcmdata/include/dcmtk/dcmdata/libi2d/i2djpgs.h

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation