EOF filter is used to detide an ongoing tsunami record at a DART buoy.

The first frame in each QuickTime movie shows a section of a DART record containing a historical tsunami (black dots, a mix of 15-min (standard reporting mode) and 1-min (event mode) measurements), a tidal estimate with a low-pass Butterworth filter (cut-off at 3 hours) (red), and a difference of the two used as a reference tsunami signal (bottom pane).

The rest of a movie shows tsunami signal extracted "during an event", while the data are coming in.

To imitate an event situation, a flow of 1-min data starts at a peak of either seismic or tsunamu or trigger pulse signal, whereas a flow of 15-min data is terminated 4 or 6 hours before the start of the 1-min reporting mode.

Top pane: a DART record up to a current moment (black) and a tidal estimate with an EOF filter (red). Middle pane: the difference of the two (tsunami, black) and the reference tsunami signal (cyan). Bottom pane: the difference between the reference and the EOF-filtered tsunami.