基于时间变量不断变化的正弦音调

Question

    #Sine wave calculations by vegaseat.
#The program will take in the current time that the computer has, and turn that into a
#tone that is unique to that moment in time.  It then makes an accompaning graph to
#view for easier comparison of the sound and an interesting view of the sound heard.

from Tkinter import *
from struct import pack
from math import sin, pi
import math
import time
import os


def wave():
    #time based variables
    t = time.strftime("%S", time.localtime())
    ti = time.strftime("%M", time.localtime())
    tis = float(t)
    tis = tis / 100
    tim = float(ti)
    tim = tim / 100


    root = Tk()
    root.title("The moment")

    #variables for canvas
    width = 800
    height = 600
    center = height//2
    x_increment = 2
    # width stretch
    x_factor1 = tis
    x_factor2 = tim
    # height stretch
    y_amplitude = 50

    #new canvas
    c = Canvas(width=width, height=height, bg="black")
    c.pack()

    str1 = "sin(x)=white"
    c.create_text(10, 20, anchor=SW, text=str1)

    center_line = c.create_line(0, center, width, center, fill="red")

    # create the coordinate list for the sin() curve, have to be integers
    xy1 = []
    xy2 = []
    for x in range(400):
        # x coordinates
        xy1.append(x * x_increment)
        xy2.append(x * x_increment)
        # y coordinates
        xy1.append(int(math.sin(x * x_factor1) * y_amplitude) + center)
        xy2.append(int(math.sin(x * x_factor2) * y_amplitude) + center)

    #create the lines
    sinS_line = c.create_line(xy1, fill="white")
    sinM_line = c.create_line(xy2, fill="yellow")

    root.mainloop()

def au_file(name, freq, freq1, dur, vol):
    fout = open(name, "wb")
    # header needs size, encoding=2, sampling_rate=8000, channel=1
    fout.write(".snd" + pack(">5L", 24, 8*dur, 2, 8000, 1))
    factor = 2 * pi * freq/8000
    factor1 = 2 * pi * freq1/8000
    # write data
    for seg in range(8 * dur):
        # sine wave calculations
        sin_seg = sin(seg * factor) + sin(seg * factor1)
        fout.write(pack("b", vol * 64 * sin_seg))
    fout.close()
#time based variables
t = time.strftime("%S", time.localtime())
ti = time.strftime("%M", time.localtime())
tis = float(t)
tis = tis * 100
tim = float(ti)
tim = tim * 100
os.startfile("timeSound.au")

#running it using main.
def main():
    au_file(name="timeSound.au", freq=tim, freq1=tis, dur=1000, vol=1.0)
    wave()

main()

这是我的程序，它会根据输入的分钟数生成一个正弦波音调，并且这个音调会随着时间变化（有点像）。程序会创建一个声音文件，然后播放出来。我想要的是一个实时的正弦波音调，这个音调会根据时间的变化（精确到毫秒）不断波动。这样做可能吗？如果可以的话，我该用什么工具来实现实时播放声音？还有，怎么才能让这些变量和时间连接起来，并且也能实时更新呢？

Answer 1

这里有一种处理连续变化频率的方法：

def gen_scale(samples_per_wave, samples_per_change):
    pi2 = 2 * math.pi
    rad = 0
    while (samples_per_wave > 1):
        for i in range(0, samples_per_change):
            yield math.sin(rad)
            rad = rad + pi2 / samples_per_wave
            if (rad > pi2):
                rad = rad - pi2
        samples_per_wave = samples_per_wave - 1

samples_per_wave 实际上是频率（赫兹，Hz）的倒数（也就是说，这个声音的频率会逐渐增加）。samples_per_change 则是生成器在逐步调整频率之前会产生多少个样本。