pyaudio 以非阻塞方式保存多个 .WAV 文件

Question

更新：现在我发现我们可以在回调函数中粘贴一些代码并结束了更多问题：

什么时候调用和停止回调函数？我们什么时候打开和关闭流？
回调函数可以return流数据（audio_data来自代码）。由于我们没有调用该函数，我相信 pyaudio 会在内部调用它。如何从回调中获取 return 流数据？

import pyaudio
import wave
import numpy as np
import npstreams
import time


CHUNK = 1024
FORMAT = pyaudio.paInt16
CHANNELS = 2
RATE = 44100

audio = pyaudio.PyAudio()

channel_1_frames = []
channel_2_frames = []
fulldata = np.array([])

def callback(in_data, frame_count, time_info, flag):
    global b,a,fulldata #global variables for filter coefficients and array
    
    audio_data = np.fromstring(in_data, dtype=np.int16)
   
    channel_1 = audio_data[0::CHANNELS]
    channel_2 = audio_data[1::CHANNELS]
    data1 = channel_1.tostring()
    data2 = channel_2.tostring()
    channel_1_frames.append(data1)
    channel_2_frames.append(data2)
    wf1 = wave.open('Channel_1.wav', 'wb')
    wf2 = wave.open('Channel_2.wav', 'wb')
    wf1.setnchannels(1)
    wf2.setnchannels(1)
    wf1.setsampwidth(audio.get_sample_size(FORMAT))
    wf2.setsampwidth(audio.get_sample_size(FORMAT))
    wf1.setframerate(RATE)
    wf2.setframerate(RATE)
    wf1.writeframes(b''.join(channel_1_frames))
    wf2.writeframes(b''.join(channel_2_frames))
    wf1.close()
    wf2.close()
    
    return (audio_data, pyaudio.paContinue)


stream = audio.open(format=FORMAT,
                channels=CHANNELS,
                rate=RATE,
                input=True,
                #frames_per_buffer=CHUNK,
                stream_callback=callback)

stream.start_stream()

while stream.is_active():
    time.sleep(10)
    stream.stop_stream()
stream.close()

audio.terminate()

=============================================

我正在尝试将多个频道录制到多个 .WAV 文件中。我可以用 stream.read() 和 numpy 数组分离成不同的数组，并保存到 .WAV 文件

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

print("* recording")

channel_1_frames = []
channel_2_frames = []

for i in range(0, int(RATE / CHUNK * RECORD_SECONDS)):
    data = stream.read(CHUNK)
    # convert string to numpy array
    data_array = np.frombuffer(data, dtype='int16')
    # select channel
    channel_1 = data_array[0::CHANNELS]
    channel_2 = data_array[1::CHANNELS]
    # convert numpy array to string 
    data1 = channel_1.tostring()
    data2 = channel_2.tostring()
    channel_1_frames.append(data1)
    channel_2_frames.append(data2)
stream.stop_stream()
stream.close()
audio.terminate()

但是，根据模块文档，https://people.csail.mit.edu/hubert/pyaudio/docs/#class-stream，它说 stream.read() 和 stream.write() 不应该用于非阻塞。

我从 Github 中找到了一个很好的非阻塞 pyaudio 示例：https://gist.github.com/sloria/5693955 哪个没有使用 stream.read().

我不确定我是否可以在没有 stream.read() 的情况下读取和转换 steam numpy 数组那么是否仍然可以将流导出到不同的 .WAV 中？并使其非阻塞？

谢谢

Answer 1

随着我在编码方面学到更多，我找到了答案。

A1：回调函数运行随流停止

######open stream with out starting automatically
audio = pyaudio.PyAudio()
stream = audio.open(format=format,
channels=2,
rate=44100,
input=True,
frames_per_buffer=44100,
stream_callback=self.get_callback(),
start=False)

######start,stop stream
stream.start_stream()
stream.close()
audio.terminate()

A2：实时抓取数据，我们可以使用queue

self.recorded_frames = queue.Queue()
    def get_callback(self):
        def callback(in_data, frame_count, time_info, status):
            self.recorded_frames.put(np.frombuffer(in_data, dtype=np.int16))
            return in_data, pyaudio.paContinue
        return callback

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