Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_artifact_zvalue”.

  FT_ARTIFACT_ZVALUE reads the interesting segments of data from file and identifies
  artifacts by means of thresholding the z-transformed value of the preprocessed raw data.
  Depending on the preprocessing options, this method will be sensitive to EOG, muscle or
  jump artifacts.  This procedure only works on continuously recorded data.
  Use as
    [cfg, artifact] = ft_artifact_zvalue(cfg)
  with the configuration options
    cfg.dataset     = string with the filename
    cfg.headerfile  = string with the filename
    cfg.datafile    = string with the filename
  and optionally
  Alternatively you can use it as
    [cfg, artifact] = ft_artifact_zvalue(cfg, data)
  where the input data is a structure as obtained from FT_PREPROCESSING.
  The required configuration settings are:
    cfg.trl         = structure that defines the data segments of interest. See FT_DEFINETRIAL
    cfg.continuous  = 'yes' or 'no' whether the file contains continuous data (default   = 'yes')
  If you encounter difficulties with memory usage, you can use
    cfg.memory = 'low' or 'high', whether to be memory or computationally efficient, respectively (default = 'high')
  The optional configuration settings (see below) are:
    cfg.artfctdef.zvalue.artfctpeak  = 'yes' or 'no'
    cfg.artfctdef.zvalue.interactive = 'yes' or 'no'
  If you specify artfctpeak='yes', the maximum value of the artifact within its range
  will be found and saved into cfg.artfctdef.zvalue.peaks.
  If you specify interactive='yes', a GUI will be started and you can manually
  accept/reject detected artifacts, and/or change the threshold. To control the
  graphical interface via keyboard, use the following keys:
      q                 : Stop
      comma             : Step to the previous artifact trial
      a                 : Specify artifact trial to display
      period            : Step to the next artifact trial
      x                 : Step 10 trials back
      leftarrow         : Step to the previous trial
      t                 : Specify trial to display
      rightarrow        : Step to the next trial
      c                 : Step 10 trials forward
      k                 : Keep trial
      space             : Mark complete trial as artifact
      r                 : Mark part of trial as artifact
      downarrow         : Shift the z-threshold down
      z                 : Specify the z-threshold
      uparrow           : Shift the z-threshold down
  Use also, e.g. as input to DSS option of ft_componentanalysis
  cfg.artfctdef.zvalue.artfctpeakrange=[-0.25 0.25], for example to indicate range
  around peak to include, saved into cfg.artfctdef.zvalue.dssartifact. The default is
  [0 0]. Range will respect trial boundaries (i.e. be shorter if peak is near
  beginning or end of trial). Samples between trials will be removed; thus this won't
  match .sampleinfo of the data structure.
  Configuration settings related to the preprocessing of the data are
    cfg.artfctdef.zvalue.lpfilter      = 'no' or 'yes'  lowpass filter
    cfg.artfctdef.zvalue.hpfilter      = 'no' or 'yes'  highpass filter
    cfg.artfctdef.zvalue.bpfilter      = 'no' or 'yes'  bandpass filter
    cfg.artfctdef.zvalue.bsfilter      = 'no' or 'yes'  bandstop filter for line noise removal
    cfg.artfctdef.zvalue.dftfilter     = 'no' or 'yes'  line noise removal using discrete fourier transform
    cfg.artfctdef.zvalue.medianfilter  = 'no' or 'yes'  jump preserving median filter
    cfg.artfctdef.zvalue.lpfreq        = lowpass  frequency in Hz
    cfg.artfctdef.zvalue.hpfreq        = highpass frequency in Hz
    cfg.artfctdef.zvalue.bpfreq        = bandpass frequency range, specified as [low high] in Hz
    cfg.artfctdef.zvalue.bsfreq        = bandstop frequency range, specified as [low high] in Hz
    cfg.artfctdef.zvalue.lpfiltord     = lowpass  filter order
    cfg.artfctdef.zvalue.hpfiltord     = highpass filter order
    cfg.artfctdef.zvalue.bpfiltord     = bandpass filter order
    cfg.artfctdef.zvalue.bsfiltord     = bandstop filter order
    cfg.artfctdef.zvalue.medianfiltord = length of median filter
    cfg.artfctdef.zvalue.lpfilttype    = digital filter type, 'but' (default) or 'firws' or 'fir' or 'firls'
    cfg.artfctdef.zvalue.hpfilttype    = digital filter type, 'but' (default) or 'firws' or 'fir' or 'firls'
    cfg.artfctdef.zvalue.bpfilttype    = digital filter type, 'but' (default) or 'firws' or 'fir' or 'firls'
    cfg.artfctdef.zvalue.bsfilttype    = digital filter type, 'but' (default) or 'firws' or 'fir' or 'firls'
    cfg.artfctdef.zvalue.detrend       = 'no' or 'yes'
    cfg.artfctdef.zvalue.demean        = 'no' or 'yes'
    cfg.artfctdef.zvalue.baselinewindow = [begin end] in seconds, the default is the complete trial
    cfg.artfctdef.zvalue.hilbert       = 'no' or 'yes'
    cfg.artfctdef.zvalue.rectify       = 'no' or 'yes'
  The output argument "artifact" is a Nx2 matrix comparable to the
  "trl" matrix of FT_DEFINETRIAL. The first column of which specifying the
  beginsamples of an artifact period, the second column contains the
  endsamples of the artifactperiods.