如何连续改变正弦声音的频率？

我正在使用Pygame在一个窗口中渲染一个Sprite,我想播放一个正弦声音,其频率取决于该Sprite的y位置.我不希望信号的相位不连续.实现这一目标的最佳方法是什么？

解决方法:

我想出了这个解决方案.
将freq更改为newfreq,然后更改相位,如下所示：newphase = 2 * np.pi * t *(freq-newfreq)phase

import pyaudio
import numpy as np
from time import time

CHANNELS = 2
RATE = 44100

TT = time()
freq = 100
newfreq = 100
phase = 0
def callback(in_data, frame_count, time_info, status):
    global TT,phase,freq,newfreq
    if newfreq != freq:
        phase = 2*np.pi*TT*(freq-newfreq)+phase
        freq=newfreq
    left = (np.sin(phase+2*np.pi*freq*(TT+np.arange(frame_count)/float(RATE))))
    data = np.zeros((left.shape[0]*2,),np.float32)
    data[::2] = left
    data[1::2] = left
    TT+=frame_count/float(RATE)
    return (data, pyaudio.paContinue)

p = pyaudio.PyAudio()

stream = p.open(format=pyaudio.paFloat32,
                channels=CHANNELS,
                rate=RATE,
                output=True,
                stream_callback=callback)

stream.start_stream()
start = time()
try:
    while 1:
        now = time()     
        if now-start>1/24.:
            newfreq=200+np.sin(2*np.pi*1/20.*now)*100 #update the frequency This will depend on y on the future
            print newfreq
        start=now
finally:
    stream.stop_stream()
    stream.close()
    p.terminate()

标签：python,pygame,audio,stream,pyaudio
来源： https://codeday.me/bug/20191009/1875595.html