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Compatibility with SEPlib

RSF is mostly compatible with its predecessor, the SEPlib file format. However, there are several important differences:

  1. SEPlib program typically use the element size (esize= parameter) to distinguish between different data types: esize=4 corresponds to floating point data, while esize=8 corresponds to complex data. The typical type handling mechanism in RSF is different: RSF looks at data_format= to determine the data type.
  2. The default data form in SEPlib programs is typically XDR and not native as it is in RSF.
  3. It is possible to pipe the output of RSF programs to SEPlib:
    bash$ sfspike n1=1 | Attr want=min
    minimum value = 1 at 1
    
    However, piping the output of SEPlib programs to RSF (or, for that matter, any other non-SEPlib programs) will result in an unterminated process. Do not try
    bash$ Spike n1=1 | sfattr want=ming
    
    That happens because SEPlib uses sockets for piping and expects a socket connection from the receiving program. RSF passes data through regular Unix pipes.
  4. SEP3D is an extension of SEPlib for operating with irregularly sampled data (Biondi et al., 1996). There is no equivalent of it in RSF for the reasons explained in the beginning of this guide. Operations with irregular datasets are supported through the use of auxiliary input files that represent the geometry information.


next up previous [pdf]

Next: Reading and writing SEG-Y Up: Compatibility with other file Previous: Compatibility with other file

2012-07-19