# obspy.io.segy.core._read_segy

`_read_segy`(filename, headonly=False, byteorder=None, textual_header_encoding=None, unpack_trace_headers=False, **kwargs)

  Reads a SEG Y file and returns an ObsPy Stream object.

  Warning

  This function should NOT be called directly, it registers via the ObsPy `read()` function, call this instead.

  Parameters: | filename (str) SEG Y rev1 file to be read. headonly (bool, optional) If set to True, read only the header and omit the waveform data. byteorder (str or `None`) Determines the endianness of the file. Either `'>'` for big endian or `'<'` for little endian. If it is `None`, it will try to autodetect the endianness. The endianness is always valid for the whole file. Defaults to `None`. textual_header_encoding (str or `None`) The encoding of the textual header. Can be `'EBCDIC'`, `'ASCII'` or `None`. If it is `None`, autodetection will be attempted. Defaults to `None`. unpack_trace_headers (bool, optional) Determines whether or not all trace header values will be unpacked during reading. If `False` it will greatly enhance performance and especially memory usage with large files. The header values can still be accessed and will be calculated on the fly but tab completion will no longer work. Look in the headers.py for a list of all possible trace header values. Defaults to `False`.
  Returns: | A ObsPy `Stream` object.

  Example

      >>> from obspy import read
      >>> st = read("/path/to/00001034.sgy_first_trace")
      >>> st
      <obspy.core.stream.Stream object at 0x...>
      >>> print(st)
      1 Trace(s) in Stream:
      Seq. No. in line:    1 | 2009-06-22T14:47:37.000000Z - ... 2001 samples

### Thank you!

We would like to thank our contributors, whose efforts make this software what it is. These people have helped by writing code and documentation, and by testing. They have created and maintained this product, its associated libraries and applications, our build tools and our web sites.

#### Contributors

- Ackerley, Nick
- Allgeyer, Sebastien
- Ammon, Charles J.
- Antunes, Emanuel
- Arnarsson, Ólafur St.
- Bank, Markus
- Barsch, Robert
- Behr, Yannik
- Bernardi, Fabrizio
- Bernauer, Felix
- Bes de Berc, Maxime
- Beyreuther, Moritz
- Boltz, Shawn
- Bonaimé, Sébastien
- Carothers, Lloyd
- Chamberlain, Calum
- Chambers, Derrick
- Chen, Zhao
- Clark, Adam
- Danecek, Peter
- Egdorf, Sven
- Engels, Fabian
- Ermert, Laura
- Eulenfeld, Tom

- Fabbri, Tommaso
- Falco, Nicholas
- Fee, Jeremy
- Grellier, Clément
- Grunberg, Marc
- Hammer, Conny
- Heimann, Sebastian
- Heiniger, Lukas
- Hope, Gaute
- Igel, Heiner
- Inza, Adolfo
- Isken, Marius
- Ketchum, David
- Koymans, Mathijs
- Kremers, Simon
- Kress, Victor
- Krieger, Lars
- Krischer, Lion
- Kula, Damian
- Käufl, Paul
- Köhler, Andreas
- Lecocq, Thomas
- Leeman, John
- Legovini, Paride

- Lesage, Philippe
- Li, Yulin
- Lomax, Anthony
- Lopes, Rui L.
- MacCarthy, Jonathan
- Maggi, Alessia
- Martin, Henri
- Medlin, Andrew
- Megies, Tobias
- Meschede, Matthias
- Michelini, Alberto
- Miller, Nathaniel C.
- Morgenstern, Bernhard
- Nof, Ran Novitsky
- Panning, Mark P.
- Parker, Tom
- Pestourie, Romain
- Rapagnani, Giovanni
- Reyes, Celso
- Ringler, Adam
- Rothenhäusler, Nicolas
- Russo, Emiliano
- Sales de Andrade, Elliott

- Satriano, Claudio
- Saul, Joachim
- Scheingraber, Chris
- Schneider, Simon
- Sippl, Christian
- Snoke, Arthur
- Stange, Stefan
- Stähler, Simon C.
- Sullivan, Benjamin
- Tian, Dongdong
- Trabant, Chad
- Trani, Luca
- Uieda, Leonardo
- Walker, Andrew
- Walther, Marcus
- Wassermann, Joachim
- Williams, Mark C.
- Winkelman, Andrew
- Zaccarelli, Riccardo
- Zad, Seyed Kasra Hosseini
- Zhu, Lijun
- van Driel, Martin
- van Wijk, Kasper

#### Funds

ObsPy was partially funded by the

- German Science Foundation (DFG) via grant DFG IG 16/9-1
- German Ministry for Education and Research (BMBF), GEOTECHNOLOGIEN grant 03G0646H.
- NERA project (Network of European Research Infrastructures for Earthquake Risk Assessment and Mitigation) under the European Community's Seventh Framework Programme (FP7/2007-2013) grant agreement n° 262330
- Leibniz Institute for Applied Geophysics (LIAG)
- VERCE EU-FP7 project (no. 283543)