This documentation is for development version 0.18.dev0.


mne.chpi.filter_chpi(raw, include_line=True, t_step=0.01, t_window=0.2, verbose=None)[source]

Remove cHPI and line noise from data.


This function will only work properly if cHPI was on during the recording.

raw : instance of Raw

Raw data with cHPI information. Must be preloaded. Operates in-place.

include_line : bool

If True, also filter line noise.

t_step : float

Time step to use for estimation, default is 0.01 (10 ms).

t_window : float

Time window to use to estimate the amplitudes, default is 0.2 (200 ms).

verbose : bool, str, int, or None

If not None, override default verbose level (see mne.verbose() and Logging documentation for more).

raw : instance of Raw

The raw data.


cHPI signals are in general not stationary, because head movements act like amplitude modulators on cHPI signals. Thus it is recommended to to use this procedure, which uses an iterative fitting method, to remove cHPI signals, as opposed to notch filtering.

New in version 0.12.