specgram python

# -*- coding: utf-8 -*
import numpy as np
import scipy as sp
import wave
import struct
import matplotlib.pylab as pl

#********************参数设置********************%
winsize=512;               #%%帧长设置为512
shift=256;                 #    %%帧移设置为256
fh=600;                    #    %%设定最高基音频率
fl=60;                     #    %%设定最低基音频率
# 读取语音
filename = 'test.wav'
wavefile = wave.open(filename, 'r') # open for writing

#读取wav文件的四种信息的函数
nchannels = wavefile.getnchannels()
sample_width = wavefile.getsampwidth()
framerate = wavefile.getframerate()
numframes = wavefile.getnframes()


print 'nchannels: ' + str(nchannels)
print 'sample_width: ' +  str(sample_width)
print 'framerate: ' +  str(framerate)
print 'numframes: ' +  str(numframes)

# get wav_data
wav_data = wavefile.readframes(-1)
wav_data = np.fromstring(wav_data, 'Int16')

Time=np.linspace(0, len(wav_data)/framerate, num=len(wav_data))

pl.figure(1)
pl.title('Signal Wave...')
pl.plot(Time,wav_data)
pl.show()

#framerate就是16000, specgram！
Fs = framerate
pl.figure(2)
pl.specgram(wav_data, NFFT=1024, Fs=Fs, noverlap=512)
pl.show()