1_wave_callback.py

import pyaudio # 收集声音
import numpy as np # 处理声音数据
import matplotlib.pyplot as plt # 作图
import matplotlib as mpl 

# 按键中断: 按下按键执行该函数
def on_press(event):
    global stream, p, END
    if event.key == 'q':
        plt.close()
        stream.stop_stream()
        stream.close()
        p.terminate()
        END = True

# 输入音频参数设置
END = False
CHUNK = 1024 * 8
FORMAT = pyaudio.paInt8
CHANNEL = 1
RATE = 44100

# 中断函数
def callback(in_data, frame_count, time_info, status):
    global data
    data = in_data
    return (None, pyaudio.paContinue)

p = pyaudio.PyAudio()
stream = p.open(format=FORMAT, channels=CHANNEL, rate=RATE,\
    input=True, frames_per_buffer=CHUNK, stream_callback=callback)

# 作图的设置
mpl.rcParams['toolbar'] = 'None'
fig, ax = plt.subplots(figsize=(12,3))
fig.canvas.mpl_connect('key_press_event', on_press)
plt.subplots_adjust(left=0.001, top=0.999,right=0.999,bottom=0.001)
plt.get_current_fig_manager().set_window_title('Wave')
x = np.arange(0,CHUNK)
line, = ax.plot(x, np.random.rand(CHUNK), color='#C04851')
ax.set_xlim(0,CHUNK-1)
ax.set_ylim(-2**7,2**7)
plt.axis('off')
plt.ion()
plt.show()

# data作为全局变量, 储存缓冲区的数据, 值在callback中断函数中更新
data = None 

# 程序主体
while END==False:
    if data == None:
        continue
    data_decimal = np.frombuffer(data, dtype=np.int8)
    line.set_ydata(data_decimal)
    fig.canvas.draw()
    fig.canvas.flush_events()
    plt.pause(0.01)