FT_ARTIFACT_JUMP reads the data segments of interest from file and identifies
SQUID jump artifacts.
Use as
[cfg, artifact] = ft_artifact_jump(cfg)
with the configuration options
cfg.dataset = string with the filename
or
cfg.headerfile = string with the filename
cfg.datafile = string with the filename
and optionally
cfg.headerformat
cfg.dataformat
Alternatively you can use it as
[cfg, artifact] = ft_artifact_jump(cfg, data)
where the input data is a structure as obtained from FT_PREPROCESSING.
In both cases the configuration should also contain
cfg.trl = structure that defines the data segments of interest. See FT_DEFINETRIAL
cfg.continuous = 'yes' or 'no' whether the file contains continuous data
The data is preprocessed (again) with the following configuration parameters,
which are optimal for identifying jump artifacts.
cfg.artfctdef.jump.medianfilter = 'yes'
cfg.artfctdef.jump.medianfiltord = 9
cfg.artfctdef.jump.absdiff = 'yes'
Artifacts are identified by means of thresholding the z-transformed value
of the preprocessed data.
cfg.artfctdef.jump.channel = Nx1 cell-array with selection of channels, see FT_CHANNELSELECTION for details
cfg.artfctdef.jump.cutoff = z-value at which to threshold (default = 20)
cfg.artfctdef.jump.trlpadding = automatically determined based on the filter padding (cfg.padding)
cfg.artfctdef.jump.artpadding = automatically determined based on the filter padding (cfg.padding)
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.
To facilitate data-handling and distributed computing you can use
cfg.inputfile = ...
If you specify this option the input data will be read from a *.mat
file on disk. This mat files should contain only a single variable named 'data',
corresponding to the input structure.
See also FT_REJECTARTIFACT, FT_ARTIFACT_CLIP, FT_ARTIFACT_ECG, FT_ARTIFACT_EOG,
FT_ARTIFACT_JUMP, FT_ARTIFACT_MUSCLE, FT_ARTIFACT_THRESHOLD, FT_ARTIFACT_ZVALUE