我正在尝试录制音频并同时打印录制信号的幅度。所以我在stream.read中保存所有数据。但是当我尝试打印它们时，我有一串字节而没有整数。我想知道如何转换这些符号以获得振幅。
这是我的代码：
import pyaudio
import wave
CHUNK = 1024
FORMAT = pyaudio.paInt16
CHANNELS = 1
RATE = 44100
RECORD_SECONDS = 5
WAVE_OUTPUT_FILENAME = "output.wav"
p = pyaudio.PyAudio()
stream = p.open(format=FORMAT,
channels=CHANNELS,
rate=RATE,
input=True,
frames_per_buffer=CHUNK)
print("* recording")
frames = []
for i in range(0, int(RATE / CHUNK * RECORD_SECONDS)):
data = stream.read(CHUNK)
frames.append(data) # 2 bytes(16 bits) per channel
print("* done recording")
stream.stop_stream()
stream.close()
p.terminate()
for data in frames:
print(data)
这就是我获得的：
����# ���� !$ �� ���� �������������������������� ������ �� �� �� �� ������ ���������������������������� �� ����
％ （ ） ， . ％ ＃
答案 0 :(得分：1)
PyAudio正在为字符串中的字节提供二进制编码的音频帧。请参阅此问题的答案，了解如何打印人类可读的框架表示：
答案 1 :(得分：1)
您可以通过以下代码激励自己：
#!/usr/bin/python
# open a microphone in pyAudio and listen for taps
import pyaudio
import struct
import math
INITIAL_TAP_THRESHOLD = 0.010
FORMAT = pyaudio.paInt16
SHORT_NORMALIZE = (1.0/32768.0)
CHANNELS = 2
RATE = 44100
INPUT_BLOCK_TIME = 0.05
INPUT_FRAMES_PER_BLOCK = int(RATE*INPUT_BLOCK_TIME)
# if we get this many noisy blocks in a row, increase the threshold
OVERSENSITIVE = 15.0/INPUT_BLOCK_TIME
# if we get this many quiet blocks in a row, decrease the threshold
UNDERSENSITIVE = 120.0/INPUT_BLOCK_TIME
# if the noise was longer than this many blocks, it's not a 'tap'
MAX_TAP_BLOCKS = 0.15/INPUT_BLOCK_TIME
def get_rms( block ):
# RMS amplitude is defined as the square root of the
# mean over time of the square of the amplitude.
# so we need to convert this string of bytes into
# a string of 16-bit samples...
# we will get one short out for each
# two chars in the string.
count = len(block)/2
format = "%dh"%(count)
shorts = struct.unpack( format, block )
# iterate over the block.
sum_squares = 0.0
for sample in shorts:
# sample is a signed short in +/- 32768.
# normalize it to 1.0
n = sample * SHORT_NORMALIZE
sum_squares += n*n
return math.sqrt( sum_squares / count )
class TapTester(object):
def __init__(self):
self.pa = pyaudio.PyAudio()
self.stream = self.open_mic_stream()
self.tap_threshold = INITIAL_TAP_THRESHOLD
self.noisycount = MAX_TAP_BLOCKS+1
self.quietcount = 0
self.errorcount = 0
def stop(self):
self.stream.close()
def find_input_device(self):
device_index = None
for i in range( self.pa.get_device_count() ):
devinfo = self.pa.get_device_info_by_index(i)
print( "Device %d: %s"%(i,devinfo["name"]) )
for keyword in ["mic","input"]:
if keyword in devinfo["name"].lower():
print( "Found an input: device %d - %s"% (i,devinfo["name"]) )
device_index = i
return device_index
if device_index == None:
print( "No preferred input found; using default input device." )
return device_index
def open_mic_stream( self ):
device_index = self.find_input_device()
stream = self.pa.open( format = FORMAT,
channels = CHANNELS,
rate = RATE,
input = True,
input_device_index = device_index,
frames_per_buffer = INPUT_FRAMES_PER_BLOCK)
return stream
def tapDetected(self):
print "Tap!"
def listen(self):
try:
block = self.stream.read(INPUT_FRAMES_PER_BLOCK)
except IOError, e:
# dammit.
self.errorcount += 1
print( "(%d) Error recording: %s"%(self.errorcount,e) )
self.noisycount = 1
return
amplitude = get_rms( block )
if amplitude > self.tap_threshold:
# noisy block
self.quietcount = 0
self.noisycount += 1
if self.noisycount > OVERSENSITIVE:
# turn down the sensitivity
self.tap_threshold *= 1.1
else:
# quiet block.
if 1 <= self.noisycount <= MAX_TAP_BLOCKS:
self.tapDetected()
self.noisycount = 0
self.quietcount += 1
if self.quietcount > UNDERSENSITIVE:
# turn up the sensitivity
self.tap_threshold *= 0.9
if __name__ == "__main__":
tt = TapTester()
for i in range(1000):
tt.listen()
来自这篇文章：[Detect tap with pyaudio from live mic
您可以轻松地调整它以将RMS放在表格中并绘制表格。
答案 2 :(得分：1)
我想这个问题很老了，我在寻找其他答案时绊倒了它，但在我的项目中我使用了这样的东西。
#Lets assume the constants are defined somewhere
import struct
import pyaudio
import numpy as np
self.input = pyaudio.PyAudio().open(
format=pyaudio.paInt16,
channels=1,
rate=44100,
input=True,
output=False,
frames_per_buffer=1024,
)
wf_data = self.input.read(self.CHUNK)
wf_data = struct.unpack(str(self.CHUNK) + 'h', wf_data)
wf_data = np.array(wf_data)
paInt16 和 'h' 对应。您可以在此处找出与您的 pyaudio 格式匹配的字母。 https://docs.python.org/3/library/struct.html
归功于： https://www.youtube.com/channel/UC2W0aQEPNpU6XrkFCYifRFQ
答案 3 :(得分：0)
我认为你可以做到这一点
data = stream.read(CHUNK)
for each in data:
print(each)
答案 4 :(得分：0)
处理音频时，您可能需要信号缓冲区的 RMS（均方根）值。我相信它可以更好地“查看”音频信号的整体功率。
python 标准库作为一个名为 audioop 的模块，该模块有一个名为 rms 的函数。
import pyaudio
import time
import audioop
def get_rms():
# Creates a generator that can iterate rms values
CHUNK = 8
WIDTH = 2
CHANNELS = 1
RATE = 44100
p = pyaudio.PyAudio()
try:
stream = p.open(format=p.get_format_from_width(WIDTH),
channels=CHANNELS,
rate=RATE,
input=True,
output=False,
frames_per_buffer=CHUNK)
# wait a second to allow the stream to be setup
time.sleep(1)
while True:
# read the data
data = stream.read(CHUNK, exception_on_overflow = False)
rms = audioop.rms(data, 1)
yield rms_scaled
finally:
p.terminate()
stream.stop_stream()
stream.close()
你可以像这样使用这个功能
rms_values = get_rms()
for rms in rms_values:
print(rms)