Crewes Seismic I/O Library File Index. Function Documentation. Functions to access seimic header definitions, страница 5

int seisio_readFileDataHdr (int id, char * fileDataHdr)

Reads the data portion of the file header of a SEG-Y file.

Parameters:

id   seisio file identification number

int seisio_readFileHdr (int id, char * fileHdr)

Reads the entire file header from a SEG-Y file - both the text (EBCDIC) and data (binary) portions.

Parameters:

id   seisio file identification number

int seisio_readFileTextHdr (int id, char * fileTextHdr)

Reads the text header from a SEG-Y file.

Parameters:

id   seisio file identification number

int seisio_readTrcF4 (int id, const int trcNum, char * trcHdr, float * trcData)

Reads a trace of SEG-Y data an its associated trace header from a file.

Regardless of the file's data format, the trace data samples will be  translated to 4-byte floating point numbers and copied into the supplied  trcData array.

Parameters:

id   seisio file identification number

trcNum   The trace number to read. The first trace number in a file is 1. If a trace number of 0 is specified, the trace will be read in sequential order.

trcHdr   Pointer to a buffer of memory, 240 bytes long, to be filled with the SEG-Y  formatted trace header. The seisioTrcHdr_* functions can be used to  access/modify this trace header.

trcData   An array to be filled with nSamp data samples. Unlike trcHdr, this  array will be byte-swapped and ready for use. Call seisio_getMaxNSamp to determine how long an array you need to supply.

Returns:

status code. A value of 0 means success. SEISIO_ERR_EOF returned if the requested trace is beyond the end of file.

Todo:

Handle outrageous values of trcNum. Allow for truncated trace-length reads so we can guess at numSmp and not scan the whole file.

int seisio_readTrcI2 (int id, const int trcNum, char * trcHdr, int16 * trcData)

Reads a trace of SEG-Y data an its associated trace header from a file.

Regardless of the file's data format, the trace data samples will be  translated to 2-byte integers and copied into the supplied trcData array.

Parameters:

id   seisio file identification number

trcNum   The trace number to read. The first trace number in a file is 1. If a trace number of 0 is specified, the trace will be read in sequential order.

trcHdr   Pointer to a buffer of memory, 240 bytes long, to be filled with the SEG-Y  formatted trace header. The seisioTrcHdr_* functions can be used to  access/modify this trace header.

trcData   An array to be filled with nSamp data samples. Unlike trcHdr, this  array will be byte-swapped and ready for use. Call seisio_getMaxNSamp to determine how long an array you need to supply.

Returns:

status code. A value of 0 means success.

Todo:

Handle outrageous values of trcNum. Allow for truncated trace-length reads so we can guess at numSmp and not scan the whole file.

int seisio_readTrcI4 (int id, const int trcNum, char * trcHdr, int32 * trcData)

Reads a trace of SEG-Y data an its associated trace header from a file.

Regardless of the file's data format, the trace data samples will be  translated to 4-byte integers and copied into the supplied trcData array.

Parameters:

id   seisio file identification number

trcNum   The trace number to read. The first trace number in a file is 1. If a trace number of 0 is specified, the trace will be read in sequential order.

trcHdr   Pointer to a buffer of memory, 240 bytes long, to be filled with the SEG-Y  formatted trace header. The seisioTrcHdr_* functions can be used to  access/modify this trace header.

trcData   An array to be filled with nSamp data samples. Unlike trcHdr, this  array will be byte-swapped and ready for use. Call seisio_getMaxNSamp to determine how long an array you need to supply.

Returns:

status code. A value of 0 means success.

Todo:

Handle outrageous values of trcNum. Allow for truncated trace-length reads so we can guess at numSmp and not scan the whole file.

int seisio_setDataFmt (int id, int dataFmt)