Segy2sep - Convert from Segy to SEPlib3d
Segy2sep > stdout tape= [pars]
input tape device or seg-y filename (see notes)
[1] for buffered device (9-track reel tape drive) =0 possibly useful for 8mm EXABYTE drives
[0] silent operation
[50] ; echo every '50' traces
[tape.header] file to store ebcdic block (as ascii)
[tape.binary] file to store binary block specify full paths to ease conversion back to segy
[bh.hns] number of samples (use if bhed ns wrong)
[1] first trace to read
[INT_MAX] last trace to read
[0] allowable number of consecutive tape IO errors
[100] how many traces to look for non zero header keys
number of keys we will force to be transfered
name of the key to keep (size of nkeep)
name of keys to keep (separated by :)
number of extra keys not in SEG-Y standard
name of extra key
type of extra key (int, unsigned int, short, unsigned short, long, unsigned long, float, double)
index of extra key (0-238)
number of keys to ignore when converting
name of the key to ignore (size of nignore)
list, separated by :, of keys to ignore
[0], 1-dump all keys
[0], dump only keys listed by keep and extra
number of samples in the dataset
[5] Float data
If you want to pipe out provide the number of traces in the dataset, otherwise unpipable.
By default each trace is assumed to be SU_NFLTS (1,000,000+) in size and a copy of that length is done for each trace. Set this to something more reasonalbe (2000) for a massive speed up.
Read in a segy tape
Notes: Traditionally tape=/dev/rmt0. However, in the modern world tape device names are much less uniform. The magic name can often be deduced by 'ls /dev'. Likely man pages with the names of the tape devices are: 'mt', 'sd' 'st'. Also try 'man -k scsi', ' man mt', etc. Sometimes 'mt status' will tell the device name.
For a seg-y diskfile use tape=filename. Remark: a seg-y file is not the same as an su file. A seg-y file consists of three parts: an ebcdic header, a binary reel header, and the traces. The traces are (usually) in 32 bit IBM floating point format. An SU file consists only of the trace portion written in the native binary floats.
type: sudoc segyread for further information
ARRAY(INVALID)=(/ns,delrt,d1,f1,f2,d1,d2/)
converters