SEGY file format reader. More...

#include <VolumeViz/readers/SoVRSegyFileReader.h>

Inheritance diagram for SoVRSegyFileReader:

Public Types
enum	SegyScanningResp { SCAN_CONTINUE , SCAN_ABORT }
	SoSegyScanningCB return code. More...

enum	SegyByteOrder { SEGY_LITTLE_ENDIAN , SEGY_BIG_ENDIAN }
	Segy byte order mode. More...

enum	SegyAxisOrder { XYZ_AS_SAMPLE_INLINE_CROSSLINE , XYZ_AS_INLINE_CROSSLINE_SAMPLE }
	SegY axis order mode. More...

typedef SegyScanningResp	SoSegyScanningCB(void data, float percent, SoVRSegyFileReader reader)
	SoSegyScanningCB Callback type.

Public Types inherited from SoVolumeReader
enum	ReadError { RD_NO_ERROR , RD_FILE_NOT_FOUND_ERROR , RD_INVALID_DATA_ERROR , RD_UNSUPPORTED_DATA_TYPE_ERROR , RD_FILE_FORMAT_NOT_VALID_ERROR , RD_UNKNOWN_ERROR }
	Read error. More...

enum	Axis { X , Y , Z }
	Which axis to handle. More...

enum	ReaderType { NO_READER , AM , AVS , DICOM , GENERIC , LDM , MEMORY , RASTERSTACK , SEGY , VOL , VOX , TIFF , MRC }
	Available reader type. More...

enum	CoordinateType { COORDINATES_UNIFORM = 0 , COORDINATES_RECTILINEAR }
	Coordinate type used by this data set. More...

Public Member Functions
virtual SoType	getTypeId () const
	Returns the type identifier for this specific instance.

	SoVRSegyFileReader ()
	Constructor.

virtual ReadError	getDataChar (SbBox3f &size, SoDataSet::DataType &type, SbVec3i32 &dim) override
	Gets the characteristics (file header) of the data volume.

virtual void	getSubSlice (const SbBox2i32 &subSlice, int sliceNumber, void *data)
	Must copy the rectangular part defined by subSlice of the XY slice sliceNumber to the memory referenced by data.

virtual SbBool	setDirectCoordSysAutoDetection (SbBool autoValue)
	Sets whether or not the reader should automatically try to detect if the coordinate system used is direct (right-handed) or not.

virtual SoVolumeReader::ReaderType	getReaderType ()
	Returns the reader type, in this case, the enum value SoVolumeReader::SEGY.

virtual int	setFilename (const SbString &filename)
	Specifies the path of the file.

void	setScanningProgressCallback (SoSegyScanningCB func, void data)
	Sets a progress callback when the SEGY file is scanned.

virtual void	setSegyTextHeaderAscii (bool ascii)
	Tells whether the textual header format is ASCII or not.

virtual SbString	getSegyTextHeader ()
	Retreives the textual header (the first 3200-bytes) of the SEGY file.

virtual void	setSegyByteOrder (SegyByteOrder byteOrder)
	Sets the byte ordering to use when reading the SEGY file.

virtual SegyByteOrder	getSegyByteOrder ()
	Gets the byte ordering to use when reading the SEGY file.

virtual SbBool	setSegyFileHeader (const SoVRSegyFileHeader &fileHeader)
	Specifies the header used to read the SEGY file.

virtual SbBool	getSegyFileHeader (SoVRSegyFileHeader &fileHeader, bool readFile=false)
	Gets the SEGY file header.

virtual void	setSegyTraceHeaderBytePosition (const SoVRSegyTraceHeaderBytePosition &traceHeaderBytePosition)
	Tells the file reader where the fields are actually located (i.e., the byte positions) within the trace header.

virtual SoVRSegyTraceHeaderBytePosition	getSegyTraceHeaderBytePosition ()
	Gets the byte positions within the trace header.

virtual int	getNumTraces ()
	Returns the number of traces.

virtual SbBool	getSegyTraceHeader (int traceNumber, SoVRSegyTraceIdHeader &traceHeader)
	Gets the SEGY trace header of the given trace traceNumber .

virtual SbBool	isSegyRegular ()
	Sets the trace header of a specific trace used to read the SEGY file [OPTIONAL].

virtual void	setCrosslineRange (int from, int to, int step)
	Sets the crossline range.

virtual void	setInlineRange (int from, int to, int step)
	Sets the inline range.

virtual void	setZRange (int from, int to, int step)
	Sets the Z (time axis) range.

virtual void	getCrosslineRange (int &from, int &to, int &step)
	Gets the crossline range.

virtual void	getInlineRange (int &from, int &to, int &step)
	Gets the inline range.

virtual void	getZRange (int &from, int &to, int &step)
	Gets the Z (time axis range.

virtual SbBool	getP1P2P3Coordinates (SbVec2d &P1, SbVec2d &P2, SbVec2d &P3, SbVec2d &P4)
	Gets the P1, P2, P3 and P4 coordinates.

virtual SbBool	setDirectCoorSys (SbBool directCoord)
	Specifies if the coordinate system used is direct (right-handed) or not.

virtual void	setSegyAxisOrder (SegyAxisOrder axisOrder)
	Sets the storage order for X, Y, and Z axes.

virtual SegyAxisOrder	getSegyAxisOrder ()
	Get the storage order for X, Y, and Z axis.

virtual int	getSegyTraceData (int traceNumber, void *&traceData, int start=0, int size=-1)
	Gets the SEGY trace data of the specified trace traceNumber.

bool	getTraceCoord (const int i, const int j, SbVec2d &P)

virtual SbBool	setOutputDataType (SbBool doChange, SoDataSet::DataType type)
	Requests that the input be converted (if necessary) to the specified data type.

virtual SbBool	setInputDataRange (SbBool doChange, double min, double max)
	Requests that the input be converted from the specified range to the range depending on the output data type.

Public Member Functions inherited from SoVolumeReader
	SoVolumeReader ()
	Constructor.

virtual int	getNumSignificantBits ()
	This method is optional.

SbVec3i32	getNumVoxels (const SbVec3i32 &realSize, const SbVec3i32 &subsamplingLevel)
	Utility function provided by SoVolumeReader for subclass readers to call.

SbVec3i32	getSizeToAllocate (const SbVec3i32 &realSize, const SbVec3i32 &subsamplingLevel)
	Utility function provided by SoVolumeReader for subclass readers to call.

SbString	getFilename () const
	Returns the path of the file.

virtual SbBool	isDataConverted () const
	Returns TRUE if the data is already organized in tiles for the LDM module.

virtual void	reloadTileMinMax ()

virtual SbBool	getTileSize (SbVec3i32 &size)
	Returns tile dimensions in voxels when using data stored in tiles.

virtual SoBufferObject *	readTile (int index, const SbBox3i32 &tilePosition)
	Given an index, reads a tile if the data is organized in tiles (for LDM).

virtual SbBool	readXTraceInTile (int index, unsigned char *&buffer, const SbBox3i32 &tilePosition, const SbVec2i32 &tracePosition)
	Read directly from the data source, a trace inside a tile.

virtual SbBool	readYSliceInTile (int index, unsigned char *&buffer, const SbBox3i32 &tilePosition, const uint32_t &slicePosition)
	Read directly from the data source, an orthoslice on the Y axis (Zaxis == 1) inside a tile.

virtual SbBool	readZSliceInTile (int index, unsigned char *&buffer, const SbBox3i32 &tilePosition, const uint32_t &slicePosition)
	Read directly from the data source, an orthoslice on the Z axis (Zaxis == 2) inside a tile.

virtual SbBool	readXSliceInTile (int index, unsigned char *&buffer, const SbBox3i32 &tilePosition, const uint32_t &slicePosition)
	Read directly from the data source, an orthoslice on the X axis (Zaxis == 0) inside a tile.

virtual SbBool	isThreadSafe () const
	Should return TRUE if the reader is thread safe.

virtual SbBool	isIgnoredFile () const
	Should return TRUE if at least one file has been ignored during reading.

virtual SbString	getOriginalFilename () const
	Returns original file name from which the data has been converted to LDM format if stored in file.

virtual SbBool	getMinMax (int64_t &min, int64_t &max)
	Returns min and max for integer data type, if available.

virtual SbBool	getMinMax (double &min, double &max)
	Returns min max for float data type, if available.

virtual SbBool	getHistogram (std::vector< int64_t > &numVox)
	Returns histogram if available.

virtual SbBool	getDirectCoordSysAutoDetection ()
	Return automatic detection value.

virtual SbBool	getDirectCoordSys ()
	Return whether the coordinate system used is direct or not.

virtual SbVec2d	getTileMinMax (int index) const
	Returns the minimum and maximum data values for the given tile.

virtual SoVolumeWriter *	getConfiguredWriter ()
	Returns a volume writer that corresponds to this reader (same format, parameters, etc).

CoordinateType	getCoordinateType ()
	Returns coordinate type used by the data set.

const float *	getRectilinearCoordinates (Axis axis) const
	Returns the coordinates for the specified axis.

void	setRectilinearCoordinates (const float x, const float y, const float *z)
	Sets rectilinear coordinates for the data set.

virtual SbBool	isRGBA () const
	Returns TRUE if the data set contains RGBA color values.

void	setRGBA (const SbBool flag)
	Specifies if data must be considered as RGBA.

virtual void	closeAllHandles ()
	Close all resources that are locked by the reader.

virtual void	restoreAllHandles ()
	Restore resources that were closed by closeAllHandles().

virtual SoDEPRECATED SbBool	readTile (int index, unsigned char *&buffer, const SbBox3i32 &tilePosition)
	Given an index, reads a tile if the data is organized in tiles (for LDM).

virtual SoDEPRECATED SbBool	readTile (int index, SoBufferObject *buffer, const SbBox3i32 &tilePosition)
	Same as readTile(int index, unsigned char*& buffer, const SbBox3i32& tilePosition) but using an SoBufferObject (allocated by LDM) as the target of the data.

virtual SoDEPRECATED int	getBorderFlag ()
	Returns border (overlap) value if stored in file.

virtual SoDEPRECATED SbBool	getMinMax (int &min, int &max)
	Returns min max if stored in file.

Public Member Functions inherited from SoFieldContainer
void	setToDefaults ()
	Sets all fields in this object to their default values.

SbBool	hasDefaultValues () const
	Returns TRUE if all of the object's fields have their default values.

SbBool	fieldsAreEqual (const SoFieldContainer *fc) const
	Returns TRUE if this object's fields are exactly equal to fc's fields.

void	copyFieldValues (const SoFieldContainer *fc, SbBool copyConnections=FALSE)
	Copies the contents of fc's fields into this object's fields.

SoNONUNICODE SbBool	set (const char *fieldDataString)
	Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format.

SbBool	set (const SbString &fieldDataString)
	Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format.

void	get (SbString &fieldDataString)
	Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string.

virtual int	getFields (SoFieldList &list) const
	Appends references to all of this object's fields to resultList, and returns the number of fields appended.

virtual int	getAllFields (SoFieldList &list) const
	Returns a list of fields, including the eventIn's and eventOut's.

virtual SoField *	getField (const SbName &fieldName) const
	Returns a the field of this object whose name is fieldName.

virtual SoField *	getEventIn (const SbName &fieldName) const
	Returns a the eventIn with the given name.

virtual SoField *	getEventOut (const SbName &fieldName) const
	Returns the eventOut with the given name.

SbBool	getFieldName (const SoField *field, SbName &fieldName) const
	Returns the name of the given field in the fieldName argument.

SbBool	enableNotify (SbBool flag)
	Notification at this Field Container is enabled (if flag == TRUE) or disabled (if flag == FALSE).

SbBool	isNotifyEnabled () const
	Notification is the process of telling interested objects that this object has changed.

virtual void	setUserData (void *data)
	Sets application data.

void *	getUserData (void) const
	Gets user application data.

Public Member Functions inherited from SoBase
virtual void	touch ()
	Marks an instance as modified, simulating a change to it.

virtual SbName	getName () const
	Returns the name of an instance.

virtual void	setName (const SbName &name)
	Sets the name of an instance.

void	setSynchronizable (const bool b)
	Sets this to be a ScaleViz synchronizable object.

bool	isSynchronizable () const
	Gets the ScaleViz synchronizable state of this object.

Public Member Functions inherited from SoRefCounter
void	ref () const
	Adds a reference to an instance.

void	unref () const
	Removes a reference from an instance.

void	unrefNoDelete () const
	unrefNoDelete() should be called when it is desired to decrement the reference count, but not delete the instance if this brings the reference count to zero.

int	getRefCount () const
	Returns current reference count.

void	lock () const
	lock this instance.

void	unlock () const
	unlock this instance.

Public Member Functions inherited from SoTypedObject
SbBool	isOfType (const SoType &type) const
	Returns TRUE if this object is of the type specified in type or is derived from that type.

template<typename TypedObjectClass >
SbBool	isOfType () const
	Returns TRUE if this object is of the type of class TypedObjectClass or is derived from that class.

Static Public Member Functions
static SoType	getClassTypeId ()
	Returns the type identifier for this class.

static void	setVolumeSizeVoxels (SbBool flag)
	If TRUE, the volume extent (bounds in world coordinates) is set to 0 to dimension-1 on each axis.

Static Public Member Functions inherited from SoVolumeReader
static SoType	getClassTypeId ()
	Returns the type identifier for this class.

static SoVolumeReader *	getAppropriateReader (const SbString &filename)
	Returns a preconfigured SoVolumeReader instance that can be used to load the given file (based on the filename extension).

Static Public Member Functions inherited from SoFieldContainer
static SoType	getClassTypeId ()
	Returns the type of this class.

Static Public Member Functions inherited from SoBase
static SoType	getClassTypeId ()
	Returns type identifier for this class.

Static Public Member Functions inherited from SoTypedObject
static SoType	getClassTypeId ()
	Returns the type identifier for this class.

Additional Inherited Members
Protected Member Functions inherited from SoVolumeReader
virtual	~SoVolumeReader ()
	Destructor.

void *	getBuffer (int64_t offset, unsigned int size)
	Returns a pointer to a buffer of size bytes corresponding to a part of the file at offset bytes from the beginning of the file.

int64_t	fileSize ()
	Returns the size of the file when file I/O is handled by this class.

Static Protected Member Functions inherited from SoVolumeReader
static bool	registerVolumeReaderExtension (const SbString &fileExtension, const SoType &readerType)
	Register an SoVolumeReader class to handle a file extension.

static bool	unregisterVolumeReaderExtensions (const SoType &readerType)
	Unregister all filename extensions associated with the specified SoVolumeReader class.

static int	bytesToInt (const unsigned char *ptr, int sizeBytes)
	Utility method that returns an integer from sizeBytes bytes starting at address ptr.

static void	swapBytes (int *intPtr, int sizeBytes)
	Utility method to convert an integer into the correct architecture (little/big endian).

static void	swapBytesN (void *buffer, int numElements, int numBytesPerElement)
	Utility method to swap bytes of each element of an array of numElements elements.

static SbBool	isValidFloat (const float val)
	Utility method to check if value is a valid IEEE 754 floating point number.

static SbBox3f	adjustFlatExtent (const SbString &fileName, const SbBox3f &extent, const SbVec3i32 &dim)
	VolumeViz doesn't handles empty extent (for ex.

Protected Attributes inherited from SoVolumeReader
SoDEPRECATED SbBool	m_dataConverted

Detailed Description

SEGY file format reader.

Reader for SEGY files (SEG Y revision 1). The following data types are supported: unsigned or signed byte, short, int32, and float.

SEGY is a widely used format for storing seismic trace data, defined by the Society of Exploration Geophysicists publication "Digital Tape Standards" (http://www.seg.org). The VolumeViz reader supports all sizes of integer and float data, and can correctly determine the number of samples per trace in most cases.

The data will be mapped to the Open Inventor axes as follows:

The trace length is mapped onto the Inventor X axis (time).
The number of trace sensors per line is mapped onto the Inventor Y axis (inlines).
Z is the number of lines (crosslines).

Although in most cases the SEGY reader can automatically detect if the number of traces per line in a SEGY file is not uniform, in some cases it cannot. However, be aware that the initialization for file reading will take longer when this environment variable is set. Missing data is assigned the value zero.

Although in most cases the SEGY reader can automatically detect if the length of traces in a SEGY data file is not uniform, in some cases it cannot. However, be aware that the initialization for file reading will take significantly longer when this environment variable is set. Missing data is assigned the value zero.

In most cases the SEGY reader can automatically detect if the values in the file need to be "byte swapped", for example if the data was written on a "big-endian" machine (e.g., SPARC) and is being read on a "little-endian" machine (e.g., Intel). If necessary you can force byte swapping on or off using the environment variable IVVR_SEGY_SWAPBYTES.

A value of 1 in the format field of the SEGY header normally means that the data values were written in IBM floating point format. But in some cases the values were actually written in IEEE floating point format (which should be indicated by format = 5). Normally the SEGY reader is able to detect this, but if necessary you can specify that float values are in IEEE format by setting environment variable IVVR_SEGY_FLOATISIEEE.

If the SEGY reader fails to read the file correctly, you can set the following environment variables:

IVVR_SEGY_DEBUG=1 This outputs information of what the reader is actually doing.
IVVR_SEGY_DUMP=filename This requests that some information of the file and trace headers be written to the specified file while processing the SEGY data file. All these information can be sent to the VSG support for assitance.

Limitations: In some circontances few first traces might be skipped, typically when the first line contains only one trace (this trace might be skipped). In such a case a message warns the application of how many traces are actually skipped (throught SoDebugError).

See SoPreferences for information on using environment variables.

In some cases information such as line numbers and crossline numbers will be stored in non-standard locations in the header. Applications can specify the byte position of values within the header using the setSegyTraceHeaderBytePosition() method.
Example :

SoVRSegyFileReader* reader = new SoVRSegyFileReader;
SoVRSegyTraceHeaderBytePosition bytePos;
bytePos.setBytePosition(SoVRSegyTraceHeaderBytePosition::SEGY_INLINE   , 189);
bytePos.setBytePosition(SoVRSegyTraceHeaderBytePosition::SEGY_CROSSLINE, 193);
reader->setSegyTraceHeaderBytePosition(bytePos);
reader->setFilename(theFilePath);

Information about the range of inline / crossline numbers and the range of time values can be queried using the getInlineRange(), getCrosslineRange() and getZRange() methods.

Applications can use this class to open a SEGY file and extract information from the file directly (in other words without necessarily creating a volume data node). To get the SEGY text file header call getSegyTextHeader(). To get the SEGY binary file header call getSegyFileHeader(). To get the header of a specific trace call getSegyTraceHeader(). To get the values in a specific trace call getSegyTraceData().

Member Typedef Documentation

◆ SoSegyScanningCB

typedef SegyScanningResp SoVRSegyFileReader::SoSegyScanningCB(void *data, float percent, SoVRSegyFileReader *reader)

SoSegyScanningCB Callback type.

Definition at line 214 of file SoVRSegyFileReader.h.

Member Enumeration Documentation

◆ SegyAxisOrder

enum SoVRSegyFileReader::SegyAxisOrder

SegY axis order mode.

Enumerator
XYZ_AS_SAMPLE_INLINE_CROSSLINE	XYZ_AS_SAMPLE_INLINE_CROSSLINE.
XYZ_AS_INLINE_CROSSLINE_SAMPLE	XYZ_AS_INLINE_CROSSLINE_SAMPLE.

Definition at line 419 of file SoVRSegyFileReader.h.

◆ SegyByteOrder

enum SoVRSegyFileReader::SegyByteOrder

Segy byte order mode.

Enumerator
SEGY_LITTLE_ENDIAN	Little endian.
SEGY_BIG_ENDIAN	Big endian.

Definition at line 248 of file SoVRSegyFileReader.h.

◆ SegyScanningResp

enum SoVRSegyFileReader::SegyScanningResp

SoSegyScanningCB return code.

Enumerator
SCAN_CONTINUE
SCAN_ABORT

Definition at line 206 of file SoVRSegyFileReader.h.

Constructor & Destructor Documentation

◆ SoVRSegyFileReader()

SoVRSegyFileReader::SoVRSegyFileReader ( )

Constructor.

Member Function Documentation

◆ getClassTypeId()

static SoType SoVRSegyFileReader::getClassTypeId ( )

static

Returns the type identifier for this class.

◆ getCrosslineRange()

virtual void SoVRSegyFileReader::getCrosslineRange	(	int &	from,
		int &	to,
		int &	step
	)

virtual

Gets the crossline range.

This method returns the actual values from the file if the corresponding set method has not been called previously. Otherwise, the values previously specified with setCrosslineRange are returned.

◆ getDataChar()

virtual ReadError SoVRSegyFileReader::getDataChar	(	SbBox3f &	size,
		SoDataSet::DataType &	type,
		SbVec3i32 &	dim
	)

overridevirtual

Gets the characteristics (file header) of the data volume.

See SoDataSet::setVolumeData().
You can use the convenience method setFilename() to specify the file location, in which case you will not have to open the file yourself. Then you can use the convenience method getBuffer() to read the header in order to get the requested information.

NOTE: We strongly recommend that readers implement this version of getDataChar, introduced in VolumeViz 5.1, because it uses SbVec3i32 for the volume dimension.

Implements SoVolumeReader.

◆ getInlineRange()

virtual void SoVRSegyFileReader::getInlineRange	(	int &	from,
		int &	to,
		int &	step
	)

virtual

Gets the inline range.

This method returns the actual values from the file if the corresponding set method has not been called previously. Otherwise, the values previously specified with setInlineRange are returned.

NOTE: If the inline values are incorrect in the file, or are not retrieved correctly for any reason, getInlineRange returns (1, numLines, 1).

◆ getNumTraces()

virtual int SoVRSegyFileReader::getNumTraces ( )

virtual

Returns the number of traces.

If the file is not regular (see isSegyRegular()), an approximate number (considering it as regular) is returned (to avoid
scanning the whole file).

◆ getP1P2P3Coordinates()

virtual SbBool SoVRSegyFileReader::getP1P2P3Coordinates	(	SbVec2d &	P1,
		SbVec2d &	P2,
		SbVec2d &	P3,
		SbVec2d &	P4
	)

virtual

Gets the P1, P2, P3 and P4 coordinates.

P1, P2 are on the corners corresponding to the first line. P4, P3 are on the corners corresponding to the last line. If these points do not exist, the crossline and inline values are used instead. Returns TRUE for a right-handed coordinate system (Xline/Inline/Time).

◆ getReaderType()

virtual SoVolumeReader::ReaderType SoVRSegyFileReader::getReaderType ( )

inlinevirtual

Returns the reader type, in this case, the enum value SoVolumeReader::SEGY.

Reimplemented from SoVolumeReader.

Definition at line 190 of file SoVRSegyFileReader.h.

◆ getSegyAxisOrder()

virtual SegyAxisOrder SoVRSegyFileReader::getSegyAxisOrder ( )

virtual

Get the storage order for X, Y, and Z axis.

See setSegyAxisOrder().

◆ getSegyByteOrder()

virtual SegyByteOrder SoVRSegyFileReader::getSegyByteOrder ( )

virtual

Gets the byte ordering to use when reading the SEGY file.

◆ getSegyFileHeader()

virtual SbBool SoVRSegyFileReader::getSegyFileHeader	(	SoVRSegyFileHeader &	fileHeader,
		bool	readFile = `false`
	)

virtual

Gets the SEGY file header.

If you use this class to read a SEGY file directly, you will have to call the method SoVolumeReader::setFilename() first. Returns FALSE if the operation fails, for example, if SoVolumeReader::setFilename() was not called first. If readFile is true the file header is read from the file, otherwise the value set by setSegyFileHeader() is returned instead. If readFile is false but setSegyFileHeader() was never called, the file header is read from the file anyway.

◆ getSegyTextHeader()

virtual SbString SoVRSegyFileReader::getSegyTextHeader ( )

virtual

Retreives the textual header (the first 3200-bytes) of the SEGY file.

◆ getSegyTraceData()

virtual int SoVRSegyFileReader::getSegyTraceData	(	int	traceNumber,
		void *&	traceData,
		int	start = `0`,
		int	size = `-1`
	)

virtual

Gets the SEGY trace data of the specified trace traceNumber.

traceNumber can range from zero to the number of traces minus one. If you want to get a subset of the data, specify the start position in the trace and the number of data values ( size ). The return value is the number of data values read, or 0, if the operation failed.

If you use this class to read a SEGY file directly, you will have to call the method SoVolumeReader::setFilename() first. Additionally your application will be responsible for releasing the memory afterward. Otherwise,VolumeViz will release the memory.

This returns a pointer to an internal buffer, so if you want to call this method twice in order to get two traces, copy the first trace into your own buffer before calling this method for the second trace.

◆ getSegyTraceHeader()

virtual SbBool SoVRSegyFileReader::getSegyTraceHeader	(	int	traceNumber,
		SoVRSegyTraceIdHeader &	traceHeader
	)

virtual

Gets the SEGY trace header of the given trace traceNumber .

traceNumber can range from zero to the number of traces minus one. If you use this class to read a SEGY file directly, you will have to call the method SoVolumeReader::setFilename() first. Returns FALSE if the operation fails, for example, if SoVolumeReader::setFilename() was not called first.

◆ getSegyTraceHeaderBytePosition()

virtual SoVRSegyTraceHeaderBytePosition SoVRSegyFileReader::getSegyTraceHeaderBytePosition ( )

virtual

Gets the byte positions within the trace header.

◆ getSubSlice()

virtual void SoVRSegyFileReader::getSubSlice	(	const SbBox2i32 &	subSlice,
		int	sliceNumber,
		void *	data
	)

virtual

Must copy the rectangular part defined by subSlice of the XY slice sliceNumber to the memory referenced by data.

Slices will not always be read sequentially.

Parameters

subSlice	2D region of the slice to return.
sliceNumber	Slice number on the volume Z axis (first slice is 0).
data	Copy the data into this buffer.

You can use the convenience method getBuffer() to read data from file. Note: setFilename() must have been called previously.

Reimplemented from SoVolumeReader.

◆ getTraceCoord()

bool SoVRSegyFileReader::getTraceCoord	(	const int	i,
		const int	j,
		SbVec2d &	P
	)

◆ getTypeId()

virtual SoType SoVRSegyFileReader::getTypeId ( ) const

virtual

Returns the type identifier for this specific instance.

Reimplemented from SoVolumeReader.

◆ getZRange()

virtual void SoVRSegyFileReader::getZRange	(	int &	from,
		int &	to,
		int &	step
	)

virtual

Gets the Z (time axis range.

This method returns the actual values from the file if the corresponding set method has not been called previously. Otherwise, the values previously specified with setZRange are returned.

◆ isSegyRegular()

virtual SbBool SoVRSegyFileReader::isSegyRegular ( )

virtual

Sets the trace header of a specific trace used to read the SEGY file [OPTIONAL].

Indicates if SEGY file is regular. A file with the same number of traces in each inline and with the same number of samples for each trace is considered as regular.

◆ setCrosslineRange()

virtual void SoVRSegyFileReader::setCrosslineRange	(	int	from,
		int	to,
		int	step
	)

virtual

Sets the crossline range.

Note that this setting does not limit the amount of data read from the file (although a subclass could do that). It just specifies the range values that will be returned by getCrosslineRange().

◆ setDirectCoordSysAutoDetection()

virtual SbBool SoVRSegyFileReader::setDirectCoordSysAutoDetection ( SbBool autoValue )

virtual

Sets whether or not the reader should automatically try to detect if the coordinate system used is direct (right-handed) or not.

Default is FALSE.

Reimplemented from SoVolumeReader.

◆ setDirectCoorSys()

virtual SbBool SoVRSegyFileReader::setDirectCoorSys ( SbBool directCoord )

virtual

Specifies if the coordinate system used is direct (right-handed) or not.

Default is TRUE. If the coordinate system is direct, then samples are stored in increasing order along the positive X axis, traces are stored in increasing order along the positive Y axis, and lines are stored in increasing order along the positive Z axis. If the coordinate system in indirect, everything is the same except that lines are stored in decreasing order along the positive Z axis. NOTE: If you pass the value returned by getP1P2P3Coordinates(), the resulting LDM file will be always right handed.

Reimplemented from SoVolumeReader.

◆ setFilename()

virtual int SoVRSegyFileReader::setFilename ( const SbString & filename )

virtual

Specifies the path of the file.

Returns 0 for success. Any other return value indicates failure.

Reimplemented from SoVolumeReader.

◆ setInlineRange()

virtual void SoVRSegyFileReader::setInlineRange	(	int	from,
		int	to,
		int	step
	)

virtual

Sets the inline range.

Note that this setting does not limit the amount of data read from the file (although a subclass could do that). It just specifies the range values that will be returned by getInlineRange().

◆ setInputDataRange()

virtual SbBool SoVRSegyFileReader::setInputDataRange	(	SbBool	doChange,
		double	min,
		double	max
	)

virtual

Requests that the input be converted from the specified range to the range depending on the output data type.

This allows, for instance, if the output data type is unsigned byte, conversion of float data from range [min,max] to range [0,255]. If doChange is FALSE no range conversion is applied. Always returns TRUE.

Reimplemented from SoVolumeReader.

◆ setOutputDataType()

virtual SbBool SoVRSegyFileReader::setOutputDataType	(	SbBool	doChange,
		SoDataSet::DataType	type
	)

virtual

Requests that the input be converted (if necessary) to the specified data type.

This allows, for instance, conversion of float data to unsigned byte. If doChange is FALSE no type conversion is applied. Always returns TRUE.

Reimplemented from SoVolumeReader.

◆ setScanningProgressCallback()

void SoVRSegyFileReader::setScanningProgressCallback	(	SoSegyScanningCB *	func,
		void *	data
	)

Sets a progress callback when the SEGY file is scanned.

The SEGY file is scanned when:

1 - The trace header or the trace data is requested, if the trace length is not constant
2 - The Inline/Crossline/Z ranges are requested (see getInlineRange, getCrosslineRange, getZRange)
3 - The P1, P2 and P3 coordinates are requested (see getP1P2P3Coordinates)

◆ setSegyAxisOrder()

virtual void SoVRSegyFileReader::setSegyAxisOrder ( SegyAxisOrder axisOrder )

virtual

Sets the storage order for X, Y, and Z axes.

For example, XYZ_AS_INLINE_CROSSLINE_SAMPLE means lines along X, crosslines along Y, and samples along Z axis.

The default value is XYZ_AS_SAMPLE_INLINE_CROSSLINE, meaning samples along X, lines along Y, and crosslines along Z axis.

Note: You must call this method before:

Calling getDataChar()
Calling setFilename(), or
Setting the reader in an SoVolumeData node.

(Because the last two operations indirectly cause getDataChar() to be called.)

◆ setSegyByteOrder()

virtual void SoVRSegyFileReader::setSegyByteOrder ( SegyByteOrder byteOrder )

virtual

Sets the byte ordering to use when reading the SEGY file.

The default value is SEGY_LITTLE_ENDIAN. In most cases, even when the SEGY file is big endian, the SEGY file reader is able to detect this and read the file accordingly. This method is for the very rare case when the automatic byte order detection fails.

◆ setSegyFileHeader()

virtual SbBool SoVRSegyFileReader::setSegyFileHeader ( const SoVRSegyFileHeader & fileHeader )

virtual

Specifies the header used to read the SEGY file.

If this method is called, the reader uses the binary file header you pass rather than the actual binary file header. The following fields from the binary file header are used:

formatRevisionNumber
numTextHeaderExt
format
fixedLengthTraceFlag
hns (number of samples per trace)

Returns FALSE if the operation fails, for example, if SoVolumeReader::setFilename() was not called first.

◆ setSegyTextHeaderAscii()

virtual void SoVRSegyFileReader::setSegyTextHeaderAscii ( bool ascii )

virtual

Tells whether the textual header format is ASCII or not.

The default value is false, i.e., the textual header format is EBCDIC

◆ setSegyTraceHeaderBytePosition()

virtual void SoVRSegyFileReader::setSegyTraceHeaderBytePosition ( const SoVRSegyTraceHeaderBytePosition & traceHeaderBytePosition )

virtual

Tells the file reader where the fields are actually located (i.e., the byte positions) within the trace header.

Only the field SEGY_CDP is used (Xline position).

◆ setVolumeSizeVoxels()

static void SoVRSegyFileReader::setVolumeSizeVoxels ( SbBool flag )

static

If TRUE, the volume extent (bounds in world coordinates) is set to 0 to dimension-1 on each axis.

Else the volume extent is normalized to fit inside a unit cube centered at the origin. In other words, the size will be -.5 to +.5 along the longest dimension. FALSE by default. The application can also set the volume extent to whatever is appropriate by setting the SoVolumeData node's extent field.

◆ setZRange()

virtual void SoVRSegyFileReader::setZRange	(	int	from,
		int	to,
		int	step
	)

virtual

Sets the Z (time axis) range.

Note that this setting does not limit the amount of data read from the file (although a subclass could do that). It just specifies the range values that will be returned by getZRange().

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

VolumeViz/readers/SoVRSegyFileReader.h

Open Inventor Release 2023.2.3

Public Types

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

SEE ALSO

Member Typedef Documentation

◆ SoSegyScanningCB

Member Enumeration Documentation

◆ SegyAxisOrder

◆ SegyByteOrder

◆ SegyScanningResp

Constructor & Destructor Documentation

◆ SoVRSegyFileReader()

Member Function Documentation

◆ getClassTypeId()

◆ getCrosslineRange()

◆ getDataChar()

◆ getInlineRange()

◆ getNumTraces()

◆ getP1P2P3Coordinates()

◆ getReaderType()

◆ getSegyAxisOrder()

◆ getSegyByteOrder()

◆ getSegyFileHeader()

◆ getSegyTextHeader()

◆ getSegyTraceData()

◆ getSegyTraceHeader()

◆ getSegyTraceHeaderBytePosition()

◆ getSubSlice()

◆ getTraceCoord()

◆ getTypeId()

◆ getZRange()

◆ isSegyRegular()

◆ setCrosslineRange()

◆ setDirectCoordSysAutoDetection()

◆ setDirectCoorSys()

◆ setFilename()

◆ setInlineRange()

◆ setInputDataRange()

◆ setOutputDataType()

◆ setScanningProgressCallback()

◆ setSegyAxisOrder()

◆ setSegyByteOrder()

◆ setSegyFileHeader()

◆ setSegyTextHeaderAscii()

◆ setSegyTraceHeaderBytePosition()

◆ setVolumeSizeVoxels()

◆ setZRange()