Settings Management

Altay Sansal

Feb 12, 2026

3 min read

SegySettings Class

The SegySettings is a configuration object for the SegyFile in the environment. It allows you to customize various aspects of SEG-Y file parsing according to your needs and the specifics of your project.

It is composed of various sub-settings isolated by SEG-Y components and various topics.

  • binary: The [BinaryHeaderSettings] is used for binary header overrides when reading a SEG-Y file.

  • endianness: This setting determines the byte order that is being used in the SEG-Y file. The possible options are "big" or "little" based on Endianness. If left as None, the system defaults to Big Endian ("big").

  • revision: This setting is used to specify the SEG-Y revision number. If left as None, the system will automatically use the revision mentioned in the SEG-Y file.

  • storage_options: Provides a hook to pass parameters to storage backend. Like credentials, anonymous access, etc.

Usage

You initialize an instance of SegySettings like any other Python object, optionally providing initial values for the settings. For example:

1from segy.config import SegyHeaderOverrides
2from segy.config import SegyFileSettings
3from segy.schema import Endianness
4
5# Override extended text header count to zero
6binary_header_overrides = {"extended_text_header": 0, "segy_revision": 1}
7header_overrides = SegyHeaderOverrides(binary_header=binary_header_overrides)
8settings = SegyFileSettings(endianness=Endianness.LITTLE)

Then this can be passed to SegyFile directly.

1from segy import SegyFile
2
3file = SegyFile(uri="...", settings=settings, header_overrides=header_overrides)

If no settings are provided to SegyFile, it will take the default values.

See also

SegySettings, SegyFile, Endianness

Environment Variables

Environment variables that follow the SEGY_ format will be automatically included in your [SegyFileSettings] instance:

export SEGY_OVERRIDE_BINARY_HEADER='{"samples_per_trace": 1001, "segy_revision": 1}'
export SEGY_ENDIANNESS="big"

The environment variables will override the defaults in the SegySettings configuration, unless user overrides it again within Python.