def highpass_cnt(cnt, low_cut_off_hz, filt_order=3):
if low_cut_off_hz is None:
return cnt.copy()
b,a = scipy.signal.butter(filt_order, low_cut_off_hz/(cnt.fs/2.0),btype='highpass')
assert filter_is_stable(a)
cnt_highpassed = lfilter(cnt,b,a)
return cnt_highpassed
def bandstop_cnt(cnt, low_cut_hz, high_cut_hz, filt_order=3):
nyq_freq = 0.5 * cnt.fs
low = low_cut_hz / nyq_freq
high = high_cut_hz / nyq_freq
b, a = scipy.signal.butter(filt_order, [low, high], btype='bandstop')
assert filter_is_stable(a)
cnt_bandpassed = lfilter(cnt,b,a)
return cnt_bandpassed
def bandstop_cnt(cnt, low_cut_hz, high_cut_hz, filt_order=3):
nyq_freq = 0.5 * cnt.fs
low = low_cut_hz / nyq_freq
high = high_cut_hz / nyq_freq
b, a = scipy.signal.butter(filt_order, [low, high], btype='bandstop')
assert filter_is_stable(a)
cnt_bandpassed = lfilter(cnt, b, a)
return cnt_bandpassed
def highpass_filt_filt_cnt(cnt, low_cut_off_hz, filt_order=3):
if (low_cut_off_hz is None) or (low_cut_off_hz == 0):
log.info("Not doing any highpass, since low 0 or None")
return cnt.copy()
b, a = scipy.signal.butter(filt_order,
low_cut_off_hz / (cnt.fs / 2.0),
btype='highpass')
assert filter_is_stable(a)
cnt_highpassed = filtfilt(cnt, b, a)
return cnt_highpassed
def lowpass_filt_filt_cnt(cnt, high_cut_off_hz, filt_order=3):
if (high_cut_off_hz is None) or (high_cut_off_hz == cnt.fs):
log.info(
"Not doing any lowpass, since ince high cut hz is None or current fs"
)
b, a = scipy.signal.butter(filt_order,
high_cut_off_hz / (cnt.fs / 2.0),
btype='lowpass')
assert filter_is_stable(a)
cnt_lowpassed = filtfilt(cnt, b, a)
return cnt_lowpassed
def bandpass_cnt(cnt, low_cut_hz, high_cut_hz, filt_order=3):
"""Bandpass cnt signal using butterworth filter.
Uses lowpass in case low cut hz is exactly zero."""
if (low_cut_hz == 0 or low_cut_hz == None) and (
high_cut_hz == None):
log.info("Not doing any bandpass, since low 0 or None and "
"high None")
return cnt.copy()
if low_cut_hz == 0 or low_cut_hz == None:
log.info("Using lowpass filter since low cut hz is 0 or None")
return lowpass_cnt(cnt, high_cut_hz, filt_order=filt_order)
if high_cut_hz == None:
log.info("Using highpass filter since high cut hz is None")
return highpass_cnt(cnt, low_cut_hz, filt_order=filt_order)
nyq_freq = 0.5 * cnt.fs
low = low_cut_hz / nyq_freq
high = high_cut_hz / nyq_freq
b, a = scipy.signal.butter(filt_order, [low, high], btype='bandpass')
assert filter_is_stable(a), "Filter should be stable..."
cnt_bandpassed = lfilter(cnt,b,a)
return cnt_bandpassed
def bandpass_filt_filt_cnt(cnt, low_cut_hz, high_cut_hz, filt_order=3):
"""Bandpass cnt signal using butterworth filter.
Uses lowpass in case low cut hz is exactly zero."""
if (low_cut_hz == 0 or low_cut_hz == None) and (high_cut_hz == None
or high_cut_hz == cnt.fs):
log.info("Not doing any bandpass, since low 0 or None and "
"high None or current fs")
return cnt.copy()
if low_cut_hz == 0 or low_cut_hz == None:
log.info("Using lowpass filter since low cut hz is 0 or None")
return lowpass_filt_filt_cnt(cnt, high_cut_hz, filt_order=filt_order)
if high_cut_hz == None or high_cut_hz == cnt.fs:
log.info(
"Using highpass filter since high cut hz is None or current fs")
return highpass_filt_filt_cnt(cnt, low_cut_hz, filt_order=filt_order)
nyq_freq = 0.5 * cnt.fs
low = low_cut_hz / nyq_freq
high = high_cut_hz / nyq_freq
b, a = scipy.signal.butter(filt_order, [low, high], btype='bandpass')
assert filter_is_stable(a), "Filter should be stable..."
cnt_bandpassed = filtfilt(cnt, b, a)
return cnt_bandpassed
def highpass_filt_filt_cnt(cnt, low_cut_off_hz, filt_order=3):
b,a = scipy.signal.butter(filt_order, low_cut_off_hz/(cnt.fs/2.0),btype='highpass')
assert filter_is_stable(a)
cnt_highpassed = filtfilt(cnt,b,a)
return cnt_highpassed
def lowpass_cnt(cnt, high_cut_off_hz, filt_order=3):
b,a = scipy.signal.butter(filt_order, high_cut_off_hz/(cnt.fs/2.0),
btype='lowpass')
assert filter_is_stable(a)
cnt_lowpassed = lfilter(cnt,b,a)
return cnt_lowpassed
