def combine_frequencies(cls, specs):
"""Return new spectrogram that contains frequencies from all the
spectrograms in spec. Only returns time intersection of all of them.
Parameters
----------
spec : list
List of spectrograms of which to combine the frequencies into one.
"""
if not specs:
raise ValueError("Need at least one spectrogram.")
specs = cls.intersect_time(specs)
one = specs[0]
dtype_ = max(sp.dtype for sp in specs)
fsize = sum(sp.shape[0] for sp in specs)
new = np.zeros((fsize, one.shape[1]), dtype=dtype_)
freq_axis = np.zeros((fsize,))
for n, (data, row) in enumerate(merge(
[
[(sp, n) for n in xrange(sp.shape[0])] for sp in specs
],
key=lambda x: x[0].freq_axis[x[1]]
)):
new[n, :] = data[row, :]
freq_axis[n] = data.freq_axis[row]
params = {
'time_axis': one.time_axis, # Should be equal
'freq_axis': freq_axis,
'start': one.start,
'end': one.end,
't_delt': one.t_delt,
't_init': one.t_init,
't_label': one.t_label,
'f_label': one.f_label,
'content': one.content,
'instruments': _union(spec.instruments for spec in specs)
}
return common_base(specs)(new, **params)
def combine_frequencies(cls, specs):
""" Return new spectrogram that contains frequencies from all the
spectrograms in spec. Only returns time intersection of all of them.
Parameters
----------
spec : list
List of spectrograms of which to combine the frequencies into one.
"""
if not specs:
raise ValueError("Need at least one spectrogram.")
specs = cls.intersect_time(specs)
one = specs[0]
dtype_ = max(sp.dtype for sp in specs)
fsize = sum(sp.shape[0] for sp in specs)
new = np.zeros((fsize, one.shape[1]), dtype=dtype_)
freq_axis = np.zeros((fsize,))
for n, (data, row) in enumerate(merge(
[
[(sp, n) for n in xrange(sp.shape[0])] for sp in specs
],
key=lambda x: x[0].freq_axis[x[1]]
)):
new[n, :] = data[row, :]
freq_axis[n] = data.freq_axis[row]
params = {
'time_axis': one.time_axis, # Should be equal
'freq_axis': freq_axis,
'start': one.start,
'end': one.end,
't_delt': one.t_delt,
't_init': one.t_init,
't_label': one.t_label,
'f_label': one.f_label,
'content': one.content,
'instruments': _union(spec.instruments for spec in specs)
}
return common_base(specs)(new, **params)
def join_many(cls, specs, mk_arr=None, nonlinear=False,
maxgap=0, fill=JOIN_REPEAT):
"""Produce new Spectrogram that contains spectrograms
joined together in time.
Parameters
----------
specs : list
List of spectrograms to join together in time.
nonlinear : bool
If True, leave out gaps between spectrograms. Else, fill them with
the value specified in fill.
maxgap : float, int or None
Largest gap to allow in second. If None, allow gap of arbitrary
size.
fill : float or int
Value to fill missing values (assuming nonlinear=False) with.
Can be LinearTimeSpectrogram.JOIN_REPEAT to repeat the values for
the time just before the gap.
mk_array: function
Function that is called to create the resulting array. Can be set
to LinearTimeSpectrogram.memap(filename) to create a memory mapped
result array.
"""
# XXX: Only load header and load contents of files
# on demand.
mask = None
if mk_arr is None:
mk_arr = cls.make_array
specs = sorted(specs, key=lambda x: x.start)
freqs = specs[0].freq_axis
if not all(np.array_equal(freqs, sp.freq_axis) for sp in specs):
raise ValueError("Frequency channels do not match.")
# Smallest time-delta becomes the common time-delta.
min_delt = min(sp.t_delt for sp in specs)
dtype_ = max(sp.dtype for sp in specs)
specs = [sp.resample_time(min_delt) for sp in specs]
size = sum(sp.shape[1] for sp in specs)
data = specs[0]
start_day = data.start
xs = []
last = data
for elem in specs[1:]:
e_init = (
SECONDS_PER_DAY * (
get_day(elem.start) - get_day(start_day)
).days + elem.t_init
)
x = int((e_init - last.t_init) / min_delt)
xs.append(x)
diff = last.shape[1] - x
if maxgap is not None and -diff > maxgap / min_delt:
raise ValueError("Too large gap.")
# If we leave out undefined values, we do not want to
# add values here if x > t_res.
if nonlinear:
size -= max(0, diff)
else:
size -= diff
last = elem
# The non existing element after the last one starts after
# the last one. Needed to keep implementation below sane.
xs.append(specs[-1].shape[1])
# We do that here so the user can pass a memory mapped
# array if they'd like to.
arr = mk_arr((data.shape[0], size), dtype_)
time_axis = np.zeros((size,))
sx = 0
# Amount of pixels left out due to non-linearity. Needs to be
# considered for correct time axes.
sd = 0
for x, elem in zip(xs, specs):
diff = x - elem.shape[1]
e_time_axis = elem.time_axis
elem = elem.data
if x > elem.shape[1]:
if nonlinear:
x = elem.shape[1]
else:
# If we want to stay linear, fill up the missing
# pixels with placeholder zeros.
filler = np.zeros((data.shape[0], diff))
if fill is cls.JOIN_REPEAT:
filler[:, :] = elem[:, -1, np.newaxis]
else:
filler[:] = fill
minimum = e_time_axis[-1]
e_time_axis = np.concatenate([
e_time_axis,
np.linspace(
minimum + min_delt,
minimum + diff * min_delt,
diff
)
])
elem = np.concatenate([elem, filler], 1)
arr[:, sx:sx + x] = elem[:, :x]
if diff > 0:
if mask is None:
mask = np.zeros((data.shape[0], size), dtype=np.uint8)
mask[:, sx + x - diff:sx + x] = 1
time_axis[sx:sx + x] = e_time_axis[:x] + data.t_delt * (sx + sd)
if nonlinear:
sd += max(0, diff)
sx += x
params = {
'time_axis': time_axis,
'freq_axis': data.freq_axis,
'start': data.start,
'end': specs[-1].end,
't_delt': data.t_delt,
't_init': data.t_init,
't_label': data.t_label,
'f_label': data.f_label,
'content': data.content,
'instruments': _union(spec.instruments for spec in specs),
}
if mask is not None:
arr = ma.array(arr, mask=mask)
if nonlinear:
del params['t_delt']
return Spectrogram(arr, **params)
return common_base(specs)(arr, **params)
def join_many(cls, specs, mk_arr=None, nonlinear=False,
maxgap=0, fill=JOIN_REPEAT):
"""Produce new Spectrogram that contains spectrograms
joined together in time.
Parameters
----------
specs : list
List of spectrograms to join together in time.
nonlinear : bool
If True, leave out gaps between spectrograms. Else, fill them with
the value specified in fill.
maxgap : float, int or None
Largest gap to allow in second. If None, allow gap of arbitrary
size.
fill : float or int
Value to fill missing values (assuming nonlinear=False) with.
Can be LinearTimeSpectrogram.JOIN_REPEAT to repeat the values for
the time just before the gap.
mk_array: function
Function that is called to create the resulting array. Can be set
to LinearTimeSpectrogram.memap(filename) to create a memory mapped
result array.
"""
# XXX: Only load header and load contents of files
# on demand.
mask = None
if mk_arr is None:
mk_arr = cls.make_array
specs = sorted(specs, key=lambda x: x.start)
freqs = specs[0].freq_axis
if not all(np.array_equal(freqs, sp.freq_axis) for sp in specs):
raise ValueError("Frequency channels do not match.")
# Smallest time-delta becomes the common time-delta.
min_delt = min(sp.t_delt for sp in specs)
dtype_ = max(sp.dtype for sp in specs)
specs = [sp.resample_time(min_delt) for sp in specs]
size = sum(sp.shape[1] for sp in specs)
data = specs[0]
start_day = data.start
xs = []
last = data
for elem in specs[1:]:
e_init = (
SECONDS_PER_DAY * (
get_day(elem.start) - get_day(start_day)
).days + elem.t_init
)
x = int((e_init - last.t_init) / min_delt)
xs.append(x)
diff = last.shape[1] - x
if maxgap is not None and -diff > maxgap / min_delt:
raise ValueError("Too large gap.")
# If we leave out undefined values, we do not want to
# add values here if x > t_res.
if nonlinear:
size -= max(0, diff)
else:
size -= diff
last = elem
# The non existing element after the last one starts after
# the last one. Needed to keep implementation below sane.
xs.append(specs[-1].shape[1])
# We do that here so the user can pass a memory mapped
# array if they'd like to.
arr = mk_arr((data.shape[0], size), dtype_)
time_axis = np.zeros((size,))
sx = 0
# Amount of pixels left out due to non-linearity. Needs to be
# considered for correct time axes.
sd = 0
for x, elem in zip(xs, specs):
diff = x - elem.shape[1]
e_time_axis = elem.time_axis
elem = elem.data
if x > elem.shape[1]:
if nonlinear:
x = elem.shape[1]
else:
# If we want to stay linear, fill up the missing
# pixels with placeholder zeros.
filler = np.zeros((data.shape[0], diff))
if fill is cls.JOIN_REPEAT:
filler[:, :] = elem[:, -1, np.newaxis]
else:
filler[:] = fill
minimum = e_time_axis[-1]
e_time_axis = np.concatenate([
e_time_axis,
np.linspace(
minimum + min_delt,
minimum + diff * min_delt,
diff
)
])
elem = np.concatenate([elem, filler], 1)
arr[:, sx:sx + x] = elem[:, :x]
if diff > 0:
if mask is None:
mask = np.zeros((data.shape[0], size), dtype=np.uint8)
mask[:, sx + x - diff:sx + x] = 1
time_axis[sx:sx + x] = e_time_axis[:x] + data.t_delt * (sx + sd)
if nonlinear:
sd += max(0, diff)
sx += x
params = {
'time_axis': time_axis,
'freq_axis': data.freq_axis,
'start': data.start,
'end': specs[-1].end,
't_delt': data.t_delt,
't_init': data.t_init,
't_label': data.t_label,
'f_label': data.f_label,
'content': data.content,
'instruments': _union(spec.instruments for spec in specs),
}
if mask is not None:
arr = ma.array(arr, mask=mask)
if nonlinear:
del params['t_delt']
return Spectrogram(arr, **params)
return common_base(specs)(arr, **params)
