net.sf.jaer.util.filter
Class AngularLowpassFilter

java.lang.Object
  net.sf.jaer.util.filter.Filter
      net.sf.jaer.util.filter.LowpassFilter
          net.sf.jaer.util.filter.AngularLowpassFilter

public class AngularLowpassFilter
extends LowpassFilter

A lowpass filter that correctly handles a circular variable like an angle. Values crossing the cut do not have undue influence. The filter has a period (like 2Pi) and the cut is assumed to be at 0/period. For example, a present value of 350 deg and an input of 10 deg will push the filter by an angle of 20 degrees towards zero, instead of by -340 deg.

Author:

tobi

Field Summary

Fields inherited from class net.sf.jaer.util.filter.LowpassFilter

lastVal, lpVal

Fields inherited from class net.sf.jaer.util.filter.Filter

initialized, lastTime, tauMs, TICK_PER_MS

Constructor Summary

AngularLowpassFilter(float period)
Creates a new instance of AngularLowpassFilter

Method Summary

float	filter(float val, int time) Overrides super to handle cut.
float	getPeriod()
void	setPeriod(float period) Sets the circular period

Methods inherited from class net.sf.jaer.util.filter.LowpassFilter

getValue, setInternalValue, toString

Methods inherited from class net.sf.jaer.util.filter.Filter

get3dBFreqHz, getLastTime, getTauMs, set3dBFreqHz, setTauMs

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AngularLowpassFilter

public AngularLowpassFilter(float period)

Creates a new instance of AngularLowpassFilter

Method Detail

filter

public float filter(float val,
                    int time)

Overrides super to handle cut. If the absolute distance between the sample "value" and the internal value is shorter crossing the cut, then the

Overrides:

filter in class LowpassFilter

Parameters:

val - the new input value

time - the time in us - note units here, microseconds!

Returns:

the new filter output value

getPeriod

public float getPeriod()

setPeriod

public void setPeriod(float period)

Sets the circular period

Parameters:

period - the period, e.g. 2*Math.PI or 360