我一直在尝试使用Python中的“pyAudio”模块进行实时音频信号处理。我所做的是一个简单的例子,从麦克风读取音频数据并通过耳机播放。我尝试使用以下代码(Python 和 Cython 版本)。以为它可以工作,但不幸的是它是失速的并且不够流畅。我该如何改进代码以使其顺利运行。我的电脑是 i7,8GB RAM。
Python版本
import pyaudio
import numpy as np
RATE = 16000
CHUNK = 256
p = pyaudio.PyAudio()
player = p.open(format=pyaudio.paInt16, channels=1, rate=RATE, output=True,
frames_per_buffer=CHUNK)
stream = p.open(format=pyaudio.paInt16, channels=1, rate=RATE, input=True, frames_per_buffer=CHUNK)
for i in range(int(20*RATE/CHUNK)): #do this for 10 seconds
player.write(np.fromstring(stream.read(CHUNK),dtype=np.int16))
stream.stop_stream()
stream.close()
p.terminate()
Cython 版本
import pyaudio
import numpy as np
cdef int RATE = 16000
cdef int CHUNK = 1024
cdef int i
p = pyaudio.PyAudio()
player = p.open(format=pyaudio.paInt16, channels=1, rate=RATE, output=True, frames_per_buffer=CHUNK)
stream = p.open(format=pyaudio.paInt16, channels=1, rate=RATE, input=True, frames_per_buffer=CHUNK)
for i in range(500): #do this for 10 seconds
player.write(np.fromstring(stream.read(CHUNK),dtype=np.int16))
stream.stop_stream()
stream.close()
p.terminate()
我相信您缺少
CHUNK
作为 player.write
调用的第二个参数。
player.write(np.fromstring(stream.read(CHUNK),dtype=np.int16),CHUNK)
另外,不确定是否格式错误。但是
player.write
需要切换到 for
循环
对于每个pyaudio站点,您需要有
RATE / CHUNK * RECORD_SECONDS
而不是RECORD *RATE/CHUNK
,因为python
在*
除法之前执行/
乘法。
for i in range(int(20*RATE/CHUNK)): #do this for 10 seconds
player.write(np.fromstring(stream.read(CHUNK),dtype=np.int16),CHUNK)
stream.stop_stream()
stream.close()
p.terminate()
最后,您可能需要将
rate
增加到 44100
、CHUNK
到 1024
以及 CHANNEL
到 2
以获得更好的保真度。
下面的代码将采用默认输入设备,并将录制的内容输出到默认输出设备中。
import PyAudio
import numpy as np
p = pyaudio.PyAudio()
CHANNELS = 2
RATE = 44100
def callback(in_data, frame_count, time_info, flag):
# using Numpy to convert to array for processing
# audio_data = np.fromstring(in_data, dtype=np.float32)
return in_data, pyaudio.paContinue
stream = p.open(format=pyaudio.paFloat32,
channels=CHANNELS,
rate=RATE,
output=True,
input=True,
stream_callback=callback)
stream.start_stream()
while stream.is_active():
time.sleep(20)
stream.stop_stream()
print("Stream is stopped")
stream.close()
p.terminate()
这将运行 20 秒并停止。方法回调是您可以处理信号的地方:
audio_data = np.fromstring(in_data, dtype=np.float32)
return in_data
是将后处理数据发送回输出设备的位置。
注意 chunk 的默认参数为 1024,如 PyAudio 文档中所述: http://people.csail.mit.edu/hubert/pyaudio/docs/#pyaudio.PyAudio.open
我正在做一个类似的项目。我修改了你的代码,现在摊位已经消失了。块越大,延迟越大。这就是为什么我保持低调。
import pyaudio
import numpy as np
CHUNK = 2**5
RATE = 44100
LEN = 10
p = pyaudio.PyAudio()
stream = p.open(format=pyaudio.paInt16, channels=1, rate=RATE, input=True, frames_per_buffer=CHUNK)
player = p.open(format=pyaudio.paInt16, channels=1, rate=RATE, output=True, frames_per_buffer=CHUNK)
for i in range(int(LEN*RATE/CHUNK)): #go for a LEN seconds
data = np.fromstring(stream.read(CHUNK),dtype=np.int16)
player.write(data,CHUNK)
stream.stop_stream()
stream.close()
p.terminate()