Question

所以我在pygame中制作游戏，我的问题是某种声音效果会以不同的速度播放。据我所知，它只会播放两种速度，有时它会正常播放，而另一次它可能会播放得更快。

以下是我的代码的一些部分，我会包含更多，但我无法想象问题可能出现在其他任何地方。知道是什么导致这个吗？

pygame.mixer.pre_init(44000, -16, 2, 512)
pygame.mixer.init()
pygame.init()

rainbowPip = pygame.mixer.Sound('snakey_files/sounds/score up.ogg')
allPips = [redPip,gldPip,dmdPip,crashPip,btnPip,objPip,rainbowPip]
playSound = pygame.mixer.Sound.play
stopSound = pygame.mixer.Sound.stop

    if stats1['chime'] == 'on':
        playSound(rainbowPip, -1, 0, 200)
    elif stats1['chime'] == 'off':
        stopSound(rainbowPip)

感谢。

Answer 1

通过改变采样率可以改变音频速度。对于典型的wav文件，它可以是44100，可以加倍或减半以加速或减速。

我没有完整的代码，所以我创建了一个演示代码来解释这个概念。这里输入音频文件piano.wav首先以正常速度播放，然后以原始速度的两倍运行。注意通过使用小于1的转换因子来降低速度的选项。

希望您能够在程序中使用该代码。

演示代码

import pygame, wave, time

def checkifComplete(channel):
    while channel.get_busy():     #Check if Channel is busy
        pygame.time.wait(800)  #  wait in ms
    channel.stop()

#Set speedUp / Slowdown Factor
#ChangeRATE = 0.5  # set <1 to slow down audio
ChangeRATE = 2    # set >1 to speed up audio


#Define input / output audio files
music_file = "piano.wav"
changed_file = "changed.wav"
swidth = 2

#set up the mixer
freq = 44100     # audio CD quality
bitsize = -16    # unsigned 16 bit
channels = 2     # 1 is mono, 2 is stereo
buffer = 2048    # number of samples

pygame.mixer.init(freq, bitsize, channels, buffer)
pygame.mixer.init()

#Create sound object for Audio
myAudio1 = pygame.mixer.Sound(music_file)

#Create a channel for audio
myChannel1 = pygame.mixer.Channel(1)

#Play Audio
print "Playing audio : ", music_file
myChannel1.play(myAudio1)
checkifComplete(myChannel1) #Check if Audio1 complete

#Open current audio and get parameters
currentSound  = wave.open(music_file, 'rb') #Open input file
sampleRate = currentSound.getframerate()  #Get frame rate
channels = currentSound.getnchannels()  #Get total channels
signal = currentSound.readframes(-1) #Load all frames

#Create new audio with changed parameters
newSound = wave.open(changed_file, 'wb')
newSound.setnchannels(channels)
newSound.setsampwidth(swidth)
print "sampleRate=", sampleRate
newSound.setframerate(sampleRate * ChangeRATE)
sampleRate2 = newSound.getframerate()  #Get new frame rate
print "sampleRate2=", sampleRate2
newSound.writeframes(signal)
newSound.close()

#Create sound object for Changed Audio
myAudio2 = pygame.mixer.Sound(changed_file)

#Create a channel for Changed audio
myChannel2 = pygame.mixer.Channel(2)

#Add changed audio to Channel and Play Changed Audio
print "Playing audio2 : ", changed_file
myChannel2.play(myAudio2)
checkifComplete(myChannel2)

节目输出

Python 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> ================================ RESTART ================================
>>> 
Playing audio :  piano.wav
sampleRate= 44100
sampleRate2= 88200
Playing audio2 :  changed.wav
>>>

在游戏过程中音频改变速度

1 个答案: