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hmrR_MotionArtifactByChannel

jayd1860 edited this page Apr 11, 2023 · 1 revision

UI Name :
Motion_Artifacts_By_Channel

Syntax :
[tInc,tIncCh] = hmrR_MotionArtifactByChannel(data, probe, mlActMan, tIncMan, tMotion, tMask, STDEVthresh, AMPthresh)

Description :
Identifies motion artifacts in an input data matrix d. If any active data channel exhibits a signal change greater than std_thresh or amp_thresh, then a segment of data around that time point is marked as a motion artifact. The channel-wise motion artifacts are recorded in the output matrix tIncCh. If any channel has a motion artifact, it is indicated by the vector tInc.

Inputs :

  • data: SNIRF data structure data, containing time course data
  • probe: SNIRF data structure probe, containing probe source/detector geometry
  • tIncMan: Cell array of vectors corresponding to the number of time bases in data. tIncMan has been manually excluded. 0-excluded. 1-included. Vector same length as d.
  • mlActMan: Cell array of vectors, one for each time base in data, specifying active/inactive channels with 1 meaning active, 0 meaning inactive.
  • tMotion: Check for signal change indicative of a motion artifact over time range tMotion. Units of seconds.
  • tMask: Mark data over +/- tMask seconds around the identified motion artifact as a motion artifact. Units of seconds.
  • STDEVthresh: If the signal d for any given active channel changes by more that stdev_thresh * stdev(d) over the time interval tMotion, then this time point is marked as a motion artifact. The standard deviation is determined for each channel independently.
  • AMPthresh: If the signal d for any given active channel changes by more that amp_thresh over the time interval tMotion, then this time point is marked as a motion artifact.

Outputs :

  • tInc: a vector of length time points with 1's indicating data included and 0's indicating motion artifact.
  • tIncCh: a matrix with #time points x #channels, with 1's indicating data included and 0's indicating motion artifacts on a channel by channel basis.

Usage Options :

  • Motion_Artifacts_By_Channel: [tIncAuto, tIncAutoCh] = hmrR_MotionArtifactByChannel(dod, probe, mlActMan, tIncMan, tMotion, tMask, STDEVthresh, AMPthresh)

Default Parameters :

  • tMotion: 0.5
  • tMask: 1.0
  • STDEVthresh: 50.0
  • AMPthresh: 5.00

Prerequisites :

  • Intensity_to_Delta_OD: dod = hmrR_Intensity2OD( intensity )
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