def load_signal(self, locator, dtype='d'):
"""
Loads the signal and computes the spectrogram.
dtype: the data type to store the output in. Use
single-precision floats if needed to reduce storage
requirements.
"""
from ewave import wavfile
from libtfr import fgrid, dynamic_range
from chirp.common.signal import spectrogram
from chirp.common.geom import elementlist, masker
from numpy import linspace, log10
fp = wavfile(locator)
signal = fp.read()
Fs = fp.sampling_rate
speccr = spectrogram(**self.options)
# adjust window size to get correct number of frequency bands
df = 1. * (self.options['freq_range'][1] - self.options['freq_range'][0]) / self.options['nfreq']
nfft = int(Fs / df)
spec, extent = speccr.linspect(signal, Fs / 1000, nfft=nfft)
F, ind = fgrid(Fs, nfft, self.options['freq_range']) # in Hz
spec = spec[ind, :]
T = linspace(extent[0], extent[1], spec.shape[1]) # in ms
# first convert the spectrogram to its final scale
if self.options['powscale'].startswith('log'):
# TODO calculate dynamic range of the signal for non 16 bit PCM?
spec = log10(dynamic_range(spec, 96))
# recenter spectrogram
if self.options['subtract_mean']:
spec -= spec.mean()
if self.options['mask'] != 'none':
eblfile = os.path.splitext(locator)[0] + elementlist.default_extension
if os.path.exists(eblfile):
mask = elementlist.read(eblfile)
spec = masker(boxmask=self.options['mask'] == 'box').cut(spec, mask, T, F / 1000.)
return spec.astype(dtype)
def multiplotter(outfile, config, cout=None, show_pitch=True, pitchdir=None):
"""
A coroutine for plotting a bunch of motifs on the same page. A
useful entry point for scripts that want to do something similar
to cplotpitch, but with control over which motifs get plotted.
"""
matplotlib.use('PDF')
from matplotlib.backends.backend_pdf import PdfPages as multipdf
from matplotlib.pyplot import close as close_figure
from chirp.version import version
from chirp.common.graphics import axgriditer
from chirp.common.signal import spectrogram
def gridfun(**kwargs):
from matplotlib.pyplot import subplots
return subplots(_nrows, _ncols, sharex=True, sharey=True, figsize=_figsize)
def figfun(fig):
maxx = max(ax.dataLim.x1 for ax in fig.axes)
ax = fig.axes[0]
ax.set_xticklabels('')
ax.set_yticklabels('')
ax.set_xlim(0, maxx)
for ax in fig.axes:
ax.yaxis.set_ticks_position('left')
ax.xaxis.set_ticks_position('bottom')
fig.subplots_adjust(left=0.05, right=0.95, wspace=0)
pp.savefig(fig)
close_figure(fig)
# set up plotting
pp = multipdf(outfile)
axg = axgriditer(gridfun, figfun)
spectrogram = spectrogram(configfile=config)
plt = plotter(configfile=config)
filt = postfilter.pitchfilter(configfile=config)
print >> cout, filt.options_str()
print >> cout, "* Plotting signals:"
try:
# first call to yield won't return anything
ax = None
while 1:
# receives filename from caller and returns last axes
basename = yield ax
ax = axg.next()
try:
signal, Fs, t, p = load_data(basename, filt, pitchdir)
print >> cout, "** %s" % basename
except Exception, e:
print >> cout, "** %s: error loading data (%s)" % (basename, e)
continue
spec, extent = spectrogram.dbspect(signal, Fs)
plt.plot_spectrogram(ax, spec, extent)
if show_pitch and t is not None:
plt.plot_trace(ax, t, p)
# loop will break when caller sends stop()
finally:
axg.close()
pp.close()
def __init__(self, configfile=None):
self.spectrogram = spectrogram(configfile=configfile)
self.readconfig(configfile)
self.signal = None
self.image = None
self.Fs = None
