Seismic signals are discrete samples over time. They can be single-component samples, such as one seismic channel, three-component or multi-component samples.
Processing of seismic signals is an activity that produces a new signal. Filtering is a special case of linear processing that results in a new signal having samples at the same time instants. The characteristics of the filter are added to the characteristics of the seismic channel. Examples of filtration are signal integration and differentiation, various filters with finite impulse response and infinite impulse response (FIR and IIR). On the other hand, the square of the signal or the absolute value is the processing, not the filtering, as they are non-linear. In the same way, resampling is the processing because it changes the resampling of the signal. Filtering and filtering modules are used and often necessary in the operation of other modules, e.g. a filter simulating a Wood-Anderson seismometer is needed to calculate ML.
It is also possible to filter and process the signal in the program main window. Selected seismograms are processed, and as a result, a new signal will appear in the Main Window together with the original seismograms or in place of the original seismogram. This is used e.g. to improve the visibility of seismic waves during quilting. Filtration is carried out by the filtration management module and modules implementing a specific filter.
Appropriate filters are invoked from the Filters submenu and the processing from the Processing submenu. Currently, available processing depends on the plugins used for signal processing and filtering.