ASCEE/lasp
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Added offset_t option to SLM(); removed trailing spaces

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This commit is contained in:
Casper Jansen 2022-11-10 11:39:44 +01:00
parent e405ab8eea
commit fbb14f475c
1 changed files with 14 additions and 13 deletions
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27
src/lasp/lasp_slm.py
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@ -27,35 +27,35 @@ class SLM:
Multi-channel Sound Level Meter. Input data: time data with a certain
sampling frequency. Output: time-weighted (fast/slow) sound pressure
levels in dB(A/C/Z). Possibly in octave bands.
"""
def __init__(self,
fs,
fbdesigner=None,
fbdesigner=None,
tw: TimeWeighting =TimeWeighting.fast,
fw: FreqWeighting =FreqWeighting.A,
xmin = None,
xmax = None,
include_overall=True,
level_ref_value=P_REF):
level_ref_value=P_REF,
offset_t=0):
"""
Initialize a sound level meter object.
Args:
fs: Sampling frequency of input data [Hz]
fbdesigner: FilterBankDesigner to use for creating the
fbdesigner: FilterBankDesigner to use for creating the
(fractional) octave bank filters. Set this one to None to only do
overalls
fs: Sampling frequency [Hz]
tw: Time Weighting to apply
fw: Frequency weighting to apply
xmin: Filter designator of lowest band.
xmin: Filter designator of lowest band.
xmax: Filter designator of highest band
include_overall: If true, a non-functioning filter is added which
is used to compute the overall level.
level_ref_value: Reference value for computing the levels in dB
offset_t: Offset to be added to output time data [s]
"""
self.fbdesigner = fbdesigner
@ -63,8 +63,8 @@ class SLM:
xmin = fbdesigner.xs[0]
elif fbdesigner is None:
xmin = 0
if xmax is None and self.fbdesigner is not None:
if xmax is None and self.fbdesigner is not None:
xmax = fbdesigner.xs[-1]
elif fbdesigner is None:
xmax = 0
@ -74,7 +74,8 @@ class SLM:
nfilters = len(self.xs)
if include_overall: nfilters +=1
self.include_overall = include_overall
self.offset_t = offset_t
spld = SPLFilterDesigner(fs)
if fw == FreqWeighting.A:
prefilter = spld.A_Sos_design().flatten()
@ -104,7 +105,7 @@ class SLM:
self.nom_txt.append(fbdesigner.nominal_txt(x))
if include_overall:
# Create a unit impulse response filter, every third index equals
# Create a unit impulse response filter, every third index equals
# 1, so b0 = 1 and a0 is 1 (by definition)
# a0 = 1, b0 = 1, rest is zero
sos[:,-1] = sos_overall
@ -119,7 +120,7 @@ class SLM:
# Downsampling factor, determine from single pole low pass filter time
# constant, such that aliasing is ~ allowed at 20 dB lower value
# and
# and
dsfac = cppSLM.suggestedDownSamplingFac(fs, tw[0])
if prefilter is not None:
@ -153,14 +154,14 @@ class SLM:
Ncur = levels.shape[0]
tend = tstart + Ncur / self.fs_slm
t = np.linspace(tstart, tend, Ncur, endpoint=False)
t = np.linspace(tstart, tend, Ncur, endpoint=False) + self.offset_t
self.N += Ncur
output = {}
for i, x in enumerate(self.xs):
# '31.5' to '16k'
output[self.nom_txt[i]] = {'t': t,
output[self.nom_txt[i]] = {'t': t,
'data': levels[:, [i]],
'x': x}
if self.include_overall and self.fbdesigner is not None: