#!/usr/bin/env python """ This work is licensed under a Creative Commons Attribution 3.0 Unported License. Frank Zalkow, 2012-2013 http://www.frank-zalkow.de/en/code-snippets/create-audio-spectrograms-with-python.html?i=1 """ # %matplotlib inline import numpy as np import pyaudio from matplotlib import pyplot as plt from pysndfile import sndio as snd from numpy.lib import stride_tricks """ short time fourier transform of audio signal """ STFT_WINDOWS_MSEC = 20 STFT_WINDOW_OVERLAP = 1.0 / 3 def stft(sig, frameSize, overlapFac=0.5, window=np.hanning): win = window(frameSize) hopSize = int(frameSize - np.floor(overlapFac * frameSize)) # zeros at beginning (thus center of 1st window should be for sample nr. 0) # sig = (sig*255).astype(np.uint8) count = int(np.floor(frameSize / 2.0)) samples = np.append(np.zeros(count), sig) # cols for windowing cols = int(np.ceil((len(samples) - frameSize) / float(hopSize)) + 1) # zeros at end (thus samples can be fully covered by frames) samples = np.append(samples, np.zeros(frameSize)) frames = stride_tricks.as_strided( samples, shape=(cols, frameSize), strides=(samples.strides[0] * hopSize, samples.strides[0])).copy() frames *= win return np.fft.rfft(frames) """ scale frequency axis logarithmically """ def logscale_spec(spec, sr=44100, factor=20.): timebins, freqbins = np.shape(spec) scale = np.linspace(0, 1, freqbins)**factor scale *= (freqbins - 1) / max(scale) scale = np.unique(np.round(scale)).astype(np.uint32) # create spectrogram with new freq bins newspec = np.complex128(np.zeros([timebins, len(scale)])) for i in range(0, len(scale)): if i == len(scale) - 1: newspec[:, i] = np.sum(spec[:, scale[i]:], axis=1) else: newspec[:, i] = np.sum(spec[:, scale[i]:scale[i + 1]], axis=1) # list center freq of bins allfreqs = np.abs(np.fft.fftfreq(freqbins * 2, 1. / sr)[:freqbins + 1]) freqs = [] for i in range(0, len(scale)): if i == len(scale) - 1: freqs += [np.mean(allfreqs[scale[i]:])] else: freqs += [np.mean(allfreqs[scale[i]:scale[i + 1]])] return newspec, freqs """ generate spectrogram for aiff audio with 150ms windows and 50ms overlap""" def generate_spec_frec(samples, samplerate): # samplerate, samples = wav.read(audiopath) # s = stft(samples, binsize) s = stft(samples, samplerate * STFT_WINDOWS_MSEC // 1000, STFT_WINDOW_OVERLAP) sshow, freq = logscale_spec(s, factor=1.0, sr=samplerate) # add epison so that log10 doesn't break sshow_abs = np.abs(sshow + np.finfo(sshow.dtype).eps) ims = 20. * np.log10(sshow_abs / 10e-6) ims[ims < 0] = 0 #np.finfo(sshow.dtype).eps return ims, freq def generate_sample_spectrogram(samples): ims, _ = generate_spec_frec(samples, 22050) return ims def generate_aiff_spectrogram(audiopath): samples, samplerate, _ = snd.read(audiopath) ims, _ = generate_spec_frec(samples, samplerate) return ims def plot_stft(samples, samplerate, binsize=2**10, plotpath=None, colormap="jet"): (ims, freq) = generate_spec_frec(samples, samplerate) timebins, freqbins = np.shape(ims) plt.figure(figsize=(15, 7.5)) plt.imshow( np.transpose(ims), origin="lower", aspect="auto", cmap=colormap, interpolation="none") plt.colorbar() plt.xlabel("time (s)") plt.ylabel("frequency (hz)") plt.xlim([0, timebins - 1]) plt.ylim([0, freqbins]) xlocs = np.float32(np.linspace(0, timebins - 1, 5)) plt.xticks(xlocs, [ "%.02f" % l for l in ( (xlocs * len(samples) / timebins) + (0.5 * binsize)) / samplerate ]) ylocs = np.int16(np.round(np.linspace(0, freqbins - 1, 10))) plt.yticks(ylocs, ["%.02f" % freq[i] for i in ylocs]) if plotpath: plt.savefig(plotpath, bbox_inches="tight") else: plt.show() plt.clf() def plot_aiff_stft(audiopath, binsize=2**10, plotpath=None, colormap="jet"): samples, samplerate, _ = snd.read(audiopath) plot_stft(samples, samplerate) def play_sunflower(): sample_r = snd.get_info( './outputs/audio/sunflowers-Alex-150-normal-589.aiff')[0] snd_data_f64 = snd.read( './outputs/audio/sunflowers-Alex-150-normal-589.aiff')[0] snd_data_f32 = snd_data_f64.astype(np.float32) print(snd_data_f32.shape) snd_data = snd_data_f32.tobytes() p_oup = pyaudio.PyAudio() stream = p_oup.open( format=pyaudio.paFloat32, channels=1, rate=sample_r, output=True) stream.write(snd_data) stream.close() p_oup.terminate() plot_stft(snd_data_f32, sample_r) if __name__ == '__main__': # play_sunflower() plot_aiff_stft( './outputs/story_words/Agnes/150/chicken-Agnes-150-low-1077.aiff') plot_aiff_stft( './outputs/story_words/Agnes/150/chicken-Agnes-150-medium-1762.aiff') # spec = generate_aiff_spectrogram('./outputs/story_words/Agnes/150/chicken-Agnes-150-low-1077.aiff') # print(spec.shape) # plot_aiff_stft('./outputs/sunflowers-Alex-180-normal-4763.aiff') # plot_aiff_stft('./outputs/sunflowers-Victoria-180-normal-870.aiff') # plot_aiff_stft('./outputs/sunflowers-Fred-180-phoneme-9733.aiff') # plot_aiff_stft('./outputs/sunflowers-Fred-180-normal-6515.aiff')