visualize audio signal from microphone

waveform.py

import sys
import pyaudio
import struct
import numpy as np
import matplotlib.pyplot as plt

%matplotlib tk

CHUNK = 1024 * 4
FORMAT = pyaudio.paInt16
CHANNELS = 1
RATE = 44100
#########
p = pyaudio.PyAudio()

stream = p.open(
    format=FORMAT,
    channels=CHANNELS,
    rate=RATE,
    input=True,
    output=False,
    frames_per_buffer=CHUNK
)

fig, ax = plt.subplots()

# x values go from 0 to size of CHUNK
x = np.arange(0, CHUNK)

# make a plotted line that is x long and random y values, CHUNK in length
line, = ax.plot(x, np.random.randn(CHUNK))

# set the plot limits
# x goes from 0 to CHUNK 
ax.set_xlim(0, CHUNK)
# range of a 'signed int16' is this
ax.set_ylim(-32768, 32767)

# so forever...
while True:
    # get the data from the audio source and store it as an int16
    amplitude = np.fromstring(stream.read(CHUNK), dtype='int16')
    # set the y values of line
    line.set_ydata(amplitude)
    # and draw it
    fig.canvas.draw()
    fig.canvas.flush_events()

# example of my output:
# <img src = "http://i.imgur.com/UDO5NAX.jpg">