Difference between revisions of "Contributions:DiffFilter"

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(DivideByDeltaTime)
(Parameters)
 
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===UnwrapDiff===
 
===UnwrapDiff===
  
Base at which to unwrap numerical deltas.  2*pi ( = 6.283185307179586232) is a useful base to take in order to unwrap phase differences (when unwrapped at 2*pi, the first derivative of HilbertFilter output when OutputSignal=2 yields instantaneous frequency * 2 * pi).
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Base at which to unwrap numerical deltas while computing the first derivative.  2*pi ( = 6.283185307179586232) would be the base appropriate for unwrapping phase differences. For example, HilbertFilter with OutputSignal=2 outputs instantaneous phase:  when unwrapped at 2*pi, the first derivative of this yields 2*pi * instantaneous frequency.
  
 
===DivideByDeltaTime===
 
===DivideByDeltaTime===

Latest revision as of 16:28, 28 March 2012

Synopsis

Take the derivative of a continuous time-series input wrt. time

Location

http://www.bci2000.org/svn/trunk/src/contrib/SignalProcessing/HilbertSignalProcessing/DiffFilter.cpp

Versioning

Authors

Jeremy Hill

Parameters

DiffOrder

0 = disable; 1 = first derivative; 2 = second derivative; etc

UnwrapDiff

Base at which to unwrap numerical deltas while computing the first derivative. 2*pi ( = 6.283185307179586232) would be the base appropriate for unwrapping phase differences. For example, HilbertFilter with OutputSignal=2 outputs instantaneous phase: when unwrapped at 2*pi, the first derivative of this yields 2*pi * instantaneous frequency.

DivideByDeltaTime

Select whether to return raw sample-to-sample numerical deltas, or to divide these by the time delta in seconds to approximate a true derivative.

States

None.

See also

User Reference:Filters, Contributions:SignalProcessing, Contributions:HilbertSignalProcessing