Guralp Systems CMG-DM24S12AMS User Manual
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CMG-DM24S12AMS Operator's guide
Recording in UFF format
You can instruct Scream! to record incoming data directly in UFF
format. To do this, open the Files pane of the Setup window as above
and select either UFF ASCII (.ufa) or UFF Binary (.ufb) in the Data format
drop-down menu. However, since UFF files tend to be large and do not
contain all the data gathered by the sensor, it is recommended that you
keep the initial recording in GCF format, and convert to UFF as required
using the tools provided (see below).
Files in UFF format must represent a continuous period of time. If a
discontinuity is detected in the incoming data stream, then the file which
is currently recording will be closed, and a new file opened with a
filename time stamp matching the start of the new file. This operation
will take place whatever options you have specified for Granularity,
although the Granularity options will still work. For example, if you
specify files lasting one hour, a new file will be opened on the hour,
every hour, whether or not a discontinuity occurred during the previous
hour (which will have caused a new file to be opened at that point).
Converting between UFF and other file formats
On occasion, you may need to convert files between the various data
formats supported by Scream!. For example, you may want Scream! to
record data in GCF format and convert it to UFF later, to ensure that
you retain all the data received from the sensors. The most convenient
way to convert a GCF file into UFF format is using the command-line
tool gcf2asc, available from Güralp Systems' website at
http://www.guralp.com/
. Once the program is installed, you can convert
files from a command window (click on Windows Start – Run... and
type cmd
gcf2asc your-gcf-file.gcf /uff where your-gcf-file.gcf
should be replaced with the correct filename.
By default, gcf2asc will create a file with the same name as the
original, but with a .txt extension; you may want to rename the file
produced to have a .uff or .ufa extension. Any time periods missing
from the GCF file are represented by values of –2147483647 (the lowest
possible negative number in the GCF format).
March 2004
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