SEGY file header. More...
#include <VolumeViz/readers/SoVRSegyReader.h>
Public Attributes | |
int | jobid |
int | lino |
int | reno |
short | ntrpr |
short | nart |
unsigned short | hdt |
unsigned short | dto |
unsigned short | hns |
unsigned short | nso |
short | format |
short | fold |
short | tsort |
short | vscode |
short | hsfs |
short | hsfe |
short | hslen |
short | hstyp |
short | schn |
short | hstas |
short | hstae |
short | htatyp |
short | hcorr |
short | bgrcv |
short | rcvm |
short | mfeet |
short | polyt |
short | vpol |
short | hunass1 [120] |
unsigned short | formatRevisionNumber |
short | fixedLengthTraceFlag |
short | numTextHeaderExt |
short | hunass2 [47] |
This class encapsulates the contents of a SEGY file header (SEGY is a widely used format for storing seismic data). It is used to query this information from the SEGY file reader (see SoVRSegyFileReader::getSegyFileHeader). See also SoVRSegyTraceIdHeader.
Binary gain recovered code:
1 = Yes
2 = No.
unsigned short SoVRSegyFileHeader::dto |
Same for original field recording.
Fixed trace length flag
1: All traces in this SEG Y file are guaranteed to have the same sample interval and number of samples, as specified in hdt and hns.
2: The length of the traces in the file may vary and the number of samples in ns of the Trace Header must be examined to determine the actual length of each trace.
short SoVRSegyFileHeader::fold |
CDP fold expected per CDP ensemble.
data sample format code:
0 = Fixed point (1 bytes)
1 = Floating point (4 bytes)
2 = Fixed point (4 bytes)
3 = Fixed point (2 bytes)
4 = Fixed point w/ gain code (4 bytes)
5 = Floating point IEEE (4 bytes)
6 = Signed integer (1 byte)
7 = Not currently used
8 = Two's complement integer (1 byte)
unsigned short SoVRSegyFileHeader::formatRevisionNumber |
SEG Y Format Revision Number, 0x0100 for revision 1.0.
Correlated data traces code:
1 = No
2 = Yes.
unsigned short SoVRSegyFileHeader::hdt |
Sample interval in micro secs for this reel.
unsigned short SoVRSegyFileHeader::hns |
Number of samples per trace for this reel.
short SoVRSegyFileHeader::hsfe |
Sweep frequency at end.
short SoVRSegyFileHeader::hsfs |
Sweep frequency at start.
Sweep length (ms).
Sweep trace taper length at end (the ending taper starts at sweep length minus the taper length at end).
Sweep trace taper length at start if tapered (the taper starts at zero time and is effective for this length).
Sweep type code:
1 = Linear
2 = Parabolic
3 = Exponential
4 = Other.
Sweep trace taper type code:
1 = Linear
2 = Cos-squared
3 = Other.
short SoVRSegyFileHeader::hunass1[120] |
Unassigned.
short SoVRSegyFileHeader::hunass2[47] |
Unassigned.
Job identification number.
Line number (only one line per reel).
Measurement system code:
1 = Meters
2 = Feet.
short SoVRSegyFileHeader::nart |
Number of auxiliary traces per record.
unsigned short SoVRSegyFileHeader::nso |
Same for original field recording.
Number of data traces per record.
Number of 3200-byte Textual Header Extension records following the Binary Header.
Impulse signal polarity code:
1 = Increase in pressure or upward geophone case movement gives negative number on tape
2 = Increase in pressure or upward geophone case movement gives positive number on tape.
short SoVRSegyFileHeader::rcvm |
Amplitude recovery method code:
1 = None
2 = Spherical divergence
3 = AGC
4 = Other.
Reel number.
short SoVRSegyFileHeader::schn |
Trace number of sweep channel.
Trace sorting code:
-1 = Other
0 = Unknown
1 = As recorded (no sorting)
2 = CDP ensemble
3 = Single fold continuous profile
4 = Horizontally stacked
5 = Common source
6 = Common receiver
7 = Common offset
8 = Common mid-point.
short SoVRSegyFileHeader::vpol |
Vibratory polarity code:.
Code | Seismic signal lags pilot by |
1 | 337.5 to 22.5 degrees |
2 | 22.5 to 67.5 degrees |
3 | 67.5 to 112.5 degrees |
4 | 112.5 to 157.5 degrees |
5 | 157.5 to 202.5 degrees |
6 | 202.5 to 247.5 degrees |
7 | 247.5 to 292.5 degrees |
8 | 293.5 to 337.5 degrees |
Vertical sum code:
1 = No sum
2 = Two sum.
..
N = N sum (N = 32,767)