Brief description of class still missing. More...

#include <PasscalSegYHeader.h>

Public Member Functions
Signal::Components	component () const
double	deltaT () const
int	nSamples () const
	PasscalSegYHeader ()
void	read (QDataStream &s)
int	sampleSize () const
DateTime	t0 () const
DateTime	timePick () const
void	write (QDataStream &s) const
Static Public Member Functions
static SignalFileFormat	determineByteOrder (QString fileName)
Public Attributes
union {
struct {
char channelName [4]
qint32 channelNumber
qint16 coordinateScale
qint16 coordinateUnit
qint16 dataFormat
qint16 day
qint16 elevationScale
qint32 eventNumber
qint16 gainConstant
qint16 gainType
qint16 hour
qint32 ignored0 [3]
qint16 ignored1 [3]
qint32 ignored2 [8]
qint32 ignored3 [4]
qint16 ignored4 [6]
qint16 ignored5 [5]
qint16 ignored6 [17]
qint16 ignored7 [6]
qint16 ignored8
quint16 instrumentSerialNumber
qint32 maximumAmplitude
qint16 milliseconds
qint32 minimumAmplitude
qint16 minute
quint16 sampleInterval16
qint32 sampleInterval32
quint16 sampleNumber16
qint32 sampleNumber32
float scaleFactor
qint16 second
char sensorSerial [8]
char stationName [6]
qint16 timeBase
qint16 totalStaticCorrectionHigh
qint16 totalStaticCorrectionLow
qint16 traceIndentificationCode
qint32 traceNumberInFile
qint32 traceNumberInReel
qint16 triggerDay
qint16 triggerHour
qint16 triggerMilliseconds
qint16 triggerMinute
qint16 triggerSecond
qint16 triggerYear
qint16 year
} field
struct {
qint32 raw0 [7]
qint16 raw1 [4]
float raw10
qint16 raw11 [2]
qint32 raw12 [3]
qint32 raw2 [8]
qint16 raw3 [2]
qint32 raw4 [4]
qint16 raw5 [46]
char raw6 [18]
qint16 raw7
qint32 raw8
qint16 raw9 [8]
} raw
};

Detailed Description

Brief description of class still missing.

(from src/include/segy.h in passcal software) The PASSCAL SEGY trace format is a modified form of the SEG-Y trace format. The modification comes is because we use some of the unspecified header words to store information pertinent to the PASSCAL data. The data values for each trace are preceded by a 240 byte header. This format is given below. All integer values are stored with the most significant byte first (big endian). Data values are either 16 0r 32 bit integers depending on byte 206 of the header, the field named "data_form".

PASSCAL SEGY format is also described in many reports that can be downloaded from IRIS: http://dmc.iris.washington.edu/data One example is http://dmc.iris.washington.edu/data/reports/1999/99-002B.pdf

Constructor & Destructor Documentation

GeopsyCore::PasscalSegYHeader::PasscalSegYHeader ( )

Description of constructor still missing

References TRACE.

{
  TRACE;
  ASSERT(sizeof( PasscalSegYHeader)==240);
  memset(this, 0, 240);
}

Member Function Documentation

Signal::Components GeopsyCore::PasscalSegYHeader::component ( ) const

References GeopsyCore::Signal::East, field, GeopsyCore::Signal::North, TRACE, GeopsyCore::Signal::UndefinedComponent, and GeopsyCore::Signal::Vertical.

{
  TRACE;
  switch(field.channelNumber) {
  case 1:
  case 4:
    return Signal::Vertical;
  case 2:
  case 5:
    return Signal::North;
  case 3:
  case 6:
    return Signal::East;
  default:
    return Signal::UndefinedComponent;
  }
}

double GeopsyCore::PasscalSegYHeader::deltaT ( ) const [inline]

{return field.sampleInterval16==1 ? 1e-6*field.sampleInterval32 : 1e-6*field.sampleInterval16;}

SignalFileFormat GeopsyCore::PasscalSegYHeader::determineByteOrder ( QString fileName ) [static]

References QGpCoreTools::endl(), GeopsyCore::SignalFileFormat::PasscalSegYBigEndian, GeopsyCore::SignalFileFormat::PasscalSegYLittleEndian, QGpCoreTools::tr(), TRACE, and GeopsyCore::SignalFileFormat::Unknown.

Referenced by GeopsyCore::SignalFileFormat::fromContent(), and GeopsyCore::SignalFileFormat::fromSuffix().

{
  TRACE;
  QFile f(fileName);
  if( !f.open(QIODevice::ReadOnly) ) {
    return SignalFileFormat::Unknown;
  }
  QDataStream s(&f);
#if(QT_VERSION >= QT_VERSION_CHECK(4, 6, 0))
  s.setFloatingPointPrecision(QDataStream::SinglePrecision);
#endif
  s.setByteOrder(QDataStream::LittleEndian);
  bool littleEndian=canReadAll(s, f.size());
  f.seek(0);
  s.setByteOrder(QDataStream::BigEndian);
  bool bigEndian=canReadAll(s, f.size());
  if((littleEndian && bigEndian) || (!littleEndian && !bigEndian)) {
    App::stream() << tr("Cannot determine byte order for PASSCAL SEGY format.") << endl;
    return SignalFileFormat::Unknown;
  } else if(littleEndian) {
    return SignalFileFormat::PasscalSegYLittleEndian;
  } else {
    return SignalFileFormat::PasscalSegYBigEndian;
  }
}

int GeopsyCore::PasscalSegYHeader::nSamples ( ) const [inline]

{return field.sampleNumber16==32767 ? field.sampleNumber32 : field.sampleNumber16;}

void GeopsyCore::PasscalSegYHeader::read ( QDataStream & s )

References raw, and TRACE.

{
  TRACE;
  for(int i=0;i<7;i++) s >> raw.raw0[i];
  for(int i=0;i<4;i++) s >> raw.raw1[i];
  for(int i=0;i<8;i++) s >> raw.raw2[i];
  for(int i=0;i<2;i++) s >> raw.raw3[i];
  for(int i=0;i<4;i++) s >> raw.raw4[i];
  for(int i=0;i<46;i++) s >> raw.raw5[i];
  s.readRawData(raw.raw6, 18);
  s >> raw.raw7;
  s >> raw.raw8;
  for(int i=0;i<8;i++) s >> raw.raw9[i];
  s >> raw.raw10;
  for(int i=0;i<2;i++) s >> raw.raw11[i];
  for(int i=0;i<3;i++) s >> raw.raw12[i];
}

int GeopsyCore::PasscalSegYHeader::sampleSize ( ) const [inline]

{return field.dataFormat==0 ? 2 : 4;}

DateTime GeopsyCore::PasscalSegYHeader::t0 ( ) const

References QGpCoreTools::DateTime::addDays(), QGpCoreTools::DateTime::addSeconds(), field, and TRACE.

{
  TRACE;
  DateTime t(QDateTime(QDate(field.year , 1, 1), QTime(field.hour, field.minute, field.second)));
  t.addDays(field.day-1);
  t.addSeconds(0.001*field.milliseconds);
  return t;
}

DateTime GeopsyCore::PasscalSegYHeader::timePick ( ) const

References QGpCoreTools::DateTime::addDays(), QGpCoreTools::DateTime::addSeconds(), field, and TRACE.

{
  TRACE;
  DateTime t(QDateTime(QDate(field.triggerYear , 1, 1), QTime(field.triggerHour, field.triggerMinute, field.triggerSecond)));
  t.addDays(field.triggerDay-1);
  t.addSeconds(0.001*field.triggerMilliseconds);
  return t;
}

void GeopsyCore::PasscalSegYHeader::write ( QDataStream & s ) const

References raw, and TRACE.

{
  TRACE;
  for(int i=0;i<7;i++) s << raw.raw0[i];
  for(int i=0;i<4;i++) s << raw.raw1[i];
  for(int i=0;i<8;i++) s << raw.raw2[i];
  for(int i=0;i<2;i++) s << raw.raw3[i];
  for(int i=0;i<4;i++) s << raw.raw4[i];
  for(int i=0;i<46;i++) s << raw.raw5[i];
  s.writeRawData(raw.raw6, 18);
  s << raw.raw7;
  s << raw.raw8;
  for(int i=0;i<8;i++) s << raw.raw9[i];
  s << raw.raw10;
  for(int i=0;i<2;i++) s << raw.raw11[i];
  for(int i=0;i<3;i++) s << raw.raw12[i];
}