def wavread(filename):f = wave.open(filename,'rb')params = f.getparams()nchannels, sampwidth, framerate, nframes = params[:4]strData = f.readframes(nframes)#读取音频，字符串格式waveData = np.fromstring(strData,dtype=np.int16)#将字符串转化为int
    f.close()waveData = waveData*1.0/(max(abs(waveData)))#wave幅值归一化waveData = np.reshape(waveData,[nframes,nchannels])return waveData

# method 1: absSum
def calVolume(waveData, frameSize, overLap):wlen = len(waveData)step = frameSize - overLapframeNum = int(math.ceil(wlen*1.0/step))volume = np.zeros((frameNum,1))for i in range(frameNum):curFrame = waveData[np.arange(i*step,min(i*step+frameSize,wlen))]curFrame = curFrame - np.median(curFrame) # zero-justifiedvolume[i] = np.sum(np.abs(curFrame))return volume

def enframe(signal, nw, inc):'''将音频信号转化为帧。参数含义：signal:原始音频型号nw:每一帧的长度(这里指采样点的长度，即采样频率乘以时间间隔)inc:相邻帧的间隔（同上定义）'''signal_length=len(signal) #信号总长度if signal_length<=nw: #若信号长度小于一个帧的长度，则帧数定义为1nf=1else: #否则，计算帧的总长度nf=int(np.ceil((1.0*signal_length-nw+inc)/inc))pad_length=int((nf-1)*inc+nw) #所有帧加起来总的铺平后的长度zeros=np.zeros((pad_length-signal_length,)) #不够的长度使用0填补，类似于FFT中的扩充数组操作pad_signal=np.concatenate((signal,zeros)) #填补后的信号记为pad_signalindices=np.tile(np.arange(0,nw),(nf,1))+np.tile(np.arange(0,nf*inc,inc),(nw,1)).T  #相当于对所有帧的时间点进行抽取，得到nf*nw长度的矩阵indices=np.array(indices,dtype=np.int32) #将indices转化为矩阵frames=pad_signal[indices] #得到帧信号
#    win=np.tile(winfunc(nw),(nf,1))  #window窗函数，这里默认取1
#    return frames*win   #返回帧信号矩阵return frames

def findIndex(vol,thres):l = len(vol)ii = 0index = np.zeros(500,dtype=np.int16)for i in range(l-1):if((vol[i]-thres)*(vol[i+1]-thres)<0):index[ii]=iii = ii+1#return index[[0,-1]]return index

# 自相关函数计算基频率
def ACF(frame):flen = len(frame)acf = np.zeros(flen)for i in range(flen):acf[i] = np.sum(frame[i:flen]*frame[0:flen-i])return acf