def __calcCutOffIndex(self):
self.wavFile = Sndfile(self.wavFileName, 'r')
output = amplitude.output_signal(self.intervalWidth, 0, self.wavFile)
frequencies, amplitudes = fourier.getFFT(self.sampling_interval, output)
spectrumWidth = -abs(self.spectrumWidth)
cutOffIndex = -1
for i in range(np.size(frequencies)-1):
if ((frequencies[i]<spectrumWidth) and (frequencies[i+1]>spectrumWidth)
or frequencies[i]==spectrumWidth
or (frequencies[i]>spectrumWidth) and (frequencies[i+1]<spectrumWidth)):
cutOffIndex = i
break
if (cutOffIndex==-1):
print("given frequency was not found")
cutOffIndex = 0 # Don't cut the spectrum
self.cutOffIndex = cutOffIndex
del self.wavFile
def __calcFreqAmps(self, narrow=False, compress=False, intervalSize=10, compressionMethodString="maxMedianDifference"):
# Clear calculated data if already exists
if (compress):
self.compressedNarrowAmplitudes = []
self.compressedNarrowFrequencies = []
elif (narrow):
self.narrowAmplitudes = []
self.narrowFrequencies = []
else:
self.amplitudes = []
self.frequencies = []
self.times = []
# Compression is set to only work with narrowed data: compression of the entire spectrum is never interesting
if compress:
print("Compressing works only with narrowed data")
narrow = True
# Find the place where the cutOff should occur if the spectrum should be narrowed down
if narrow:
self.__calcCutOffIndex()
# Read the wav file
self.wavFile = Sndfile(self.wavFileName, 'r')
# Get the intervals
for intervalStartFrame in range(self.start, self.end, self.intervalStartFrequency):
startTime = intervalStartFrame*self.sampling_interval
endTime = (intervalStartFrame+self.intervalWidth)*self.sampling_interval
self.times.append((startTime+endTime)/2.0)
output = amplitude.output_signal(self.intervalWidth, intervalStartFrame, self.wavFile)
frequencies, amplitudes = fourier.getFFT(self.sampling_interval, output)
if (narrow):
frequencies, amplitudes = self.__narrowSpectrum(frequencies, amplitudes, self.cutOffIndex)
if (compress):
frequencies, amplitudes = self.__compressSpectrum(frequencies, amplitudes, intervalSize, compressionMethodString)
if (compress):
self.compressedNarrowAmplitudes.append(amplitudes)
self.compressedNarrowFrequencies = frequencies
elif (narrow):
self.narrowAmplitudes.append(amplitudes)
self.narrowFrequencies = frequencies
else:
self.amplitudes.append(amplitudes)
self.frequencies = frequencies
print (intervalStartFrame/self.fs),"/",self.end/self.fs
self.wavFile.close()
del self.wavFile
if (compress):
self.compressedNarrowDataExists = True
elif (narrow):
self.narrowDataExists = True
self.saveNarrowFrequencyAmplitudes()
else:
self.dataExists = True