Detrending

The program vdetrend can be used for removing a baseline drift. The drift can be removed either by subtracting a moving average or by subtracting a polynomial model of the drift. Available models are: linear, cubic or a polynomial of order 5. The parameter ‘-del’ specifies the number of initial timepoints that will be replaced by a mean value. The parameter ‘-linear’ can be used to apply a linear detrending as a first step before other types of detrending are used.

Example:

vdetrend -in func.v -out detrended_func.v -type demean -linear true -del 2

Parameters of ‘vdetrend’

-help

Usage information.

-in

Input file.

-out

Output file.

-type

Type of detrending [demean | linear | cubic | order5] Default: demean

-linear

Whether to first subtract linear drift. Default: true

-window

Window size in seconds (only for demeaning). Default: 100

-del

Number of initial timepoints to ignore. Default: 0