# Visualize wav file by matplotlib
# Load the required libraries:
#   * scipy
#   * numpy
#   * matplotlib
from scipy.io import wavfile
from matplotlib import pyplot as plt
import sys
import numpy as np

if len(sys.argv) < 2:
    print("Plays a wave file.\n\nUsage: %s filename.wav" % sys.argv[0])
    sys.exit(-1)

# Load the data and calculate the time of each sample
samplerate, data = wavfile.read(sys.argv[1])
times = np.arange(len(data))/float(samplerate)

# Make the plot
# You can tweak the figsize (width, height) in inches
plt.figure(figsize=(30, 4))
plt.fill_between(times, data, color='k')
plt.xlim(times[0], times[-1])
plt.xlabel('time (s)')
plt.ylabel('amplitude')
# You can set the format by changing the extension
# like .pdf, .svg, .eps
plt.savefig('plot.png', dpi=100)
plt.show()