CSS 3.0 File Format

Scream can save files in CSS flat file format (Center for Seismic Studies) version 3.0. See Recording Options. The files produced are the wfdisc table, and the .w time series data.

The .w data files are recorded using the parameters specified in the recording options, including fragmentation and directory. Filenames are created using the same date-coding system as ‘.gcf’ files, but with the ".w" extension.
The wfdisc table is stored in the base directory as specified in the Recording Options, and the filename is constructed in the same way as the .w files above, except that directory separators are replaced by underscore characters.

If a discontinuity is detected in the incoming data stream, then the currently recording ".w" file will be closed, and a new file opened with a filename timestamp matching the start of the new file. Note that this operation overrides the fragmentation (size or duration) specified in the setup.

Normal Filestamping will resume on the next fragmentation time/size interval. E.g. If 1 hour files are specified, then a new file will be opened on the hour, every hour, whether or not a discontinuity during the previous hour caused a new file to be opened. To ensure consistent datasets in the event of an unexpected shutdown, as data is written to the .w files, the wfdisc entries are updated accordingly.

The samples are stored as signed 32 bit integers (s4 or i4). The byte order used is specified in Recording Options.

See Also: Recording, GCF format, SAC format, MiniSEED format, P-SEGy format, SUDs format, GSE format, UFF format.