filter
Applies a Butterworth filter to the seismograms. The filterType can be CAUSAL or NONCAUSAL or TWOPASS, with the last two being equivalent.
Example
<filter> <lowFreqCorner> <value>50</value> <unit>SECOND</unit> </lowFreqCorner> <highFreqCorner> <value>5</value> <unit>HERTZ</unit> </highFreqCorner> <numPoles>2</numPoles> <filterType>NONCAUSAL</filterType> </filter>