python - 如何直接播放来自麦克风的输入数据

Question

我想在不缓冲的情况下播放麦克风中的许多输入数据。我试过了，但是有缓冲。这是我的代码。

import pyaudio
import wave
import urllib.request
import struct
import numpy as np
import sounddevice as sd
import matplotlib.pyplot as plt

# Callback function---------------------------------
def callback(indata, outdata, frames, time, status):
#    if status:
#        print(status)
    outdata[:] = indata
#---------------------------------------------------

# Parameters ----------------------------------------------
Window_Size = 22050 # Point
FORMAT_D = pyaudio.paFloat32; FORMAT_W = pyaudio.paInt32
CHANNELS = 1 # Mono
Sample_Rate = 22050 # Hz
dT = 1/Sample_Rate
RECORD_SECONDS = 20 # s
NOFFRAMES = int(Sample_Rate/Window_Size * RECORD_SECONDS)
WAVE_OUTPUT_FILENAME = "output.wav"
#-----------------------------------------------------------

p = pyaudio.PyAudio()

stream_D = p.open(format=FORMAT_D,
                channels=CHANNELS,
                rate=Sample_Rate,
                input=True,
                frames_per_buffer=Window_Size)

stream_W = p.open(format=FORMAT_W,
            channels=CHANNELS,
            rate=Sample_Rate,
            input=True,
            frames_per_buffer=Window_Size)

print("* recording")

frames = []

# "I think the problem appears from here"------------------------------
for i in range(0, int(Sample_Rate/Window_Size * RECORD_SECONDS)):
    data_D = stream_D.read(Window_Size)
#    data_W = stream_W.read(Window_Size)
    decoded = np.fromstring(data_D, 'Float32')
#    np.savetxt(str(i)+'ttt.txt',transform)
    sd.play(decoded,22050)
#    frames.append(data_W)
#-------------------------------------------------------

print("* done recording")

stream_D.stop_stream()
stream_D.close()
p.terminate()

#plt.plot(transform)
#plt.show()

# Save as a wave file---------------------------
#wf = wave.open(WAVE_OUTPUT_FILENAME, 'wb')
#wf.setnchannels(CHANNELS)
#wf.setsampwidth(p.get_sample_size(FORMAT_W))
#wf.setframerate(Sample_Rate)
#wf.writeframes(b''.join(frames))
#wf.close()
#-------------------------------------------

该代码执行以下操作:以1秒的间隔保存来自麦克风的输入数据，将字节数据转换为nparray数据(np.transform())，并使用扬声器播放数据(sd.play())。这段代码有效，但是在for循环再次启动时有缓冲。我想平稳播放麦克风的声音。当我首先询问时，有人建议使用回调函数，所以我添加了它，但是，我不知道如何使用它。如何摆脱缓冲？有一些例子吗？我应该使用线程还是多处理？

Answer 1

延迟是由于缓冲区大小导致的...按照以下方式使用1k缓冲区将得到可忽略不计的延迟

# Window_Size = 22050 # Point
Window_Size = 1024 # Point