问题描述
更新: 现在,我发现我们可以在回调函数中粘贴一些代码,并导致更多问题:
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何时将调用并停止回调函数?当我们打开和关闭流时?
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回调函数可以返回流数据(代码中的audio_data)。因为我们没有调用该函数,所以我相信pyaudio在内部完成它。如何从回调获取返回流数据?
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记录到多个.WAV文件中。 我可以使用stream.read()和numpy数组来做到这一点,将其分成不同的数组,然后保存到.WAV文件中
stream = audio.open(format=FORMAT,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,在模块文档https://people.csail.mit.edu/hubert/pyaudio/docs/#class-stream中,它说stream.read()和stream.write()不应用于非阻塞。
我从Github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()。
我不确定是否可以在没有stream.read()的情况下读取和转换Steam numpy数组 那么仍然可以将流导出到不同的.WAV吗?并使其不受阻碍?
谢谢
解决方法
随着我对编码的了解越来越多,我找到了答案。
A1:回调函数在流中运行和停止。
######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:要实时捕获数据,我们可以使用队列
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