170619 利用python读取wav文件及声音图形的绘制

A very convenient way to get a quick impression of how the songs of
the diverse genres “look” like is to draw a spectrogram for a set of
songs of a genre. A spectrogram is a visual representation of the
frequencies that occur in a song. It shows the intensity of the
frequencies on the y axis in the specifed time intervals on the axis;
that is, the darker the color, the stronger the frequency is in the
particular time window of the song. — Building Machine Learning
Systems with Python

代码

# -*- coding: utf-8 -*-
"""
Created on Mon Jun 19 16:59:32 2017

@author: Administrator
"""

#import scipy
from matplotlib.pyplot import specgram
from scipy.io import wavfile
sample_rate, X = wavfile.read("music.wav")
print (sample_rate, X.shape)
specgram(X, Fs=sample_rate, xextent=(0,192000))

注：这样导入wav文件会报错，所以推荐上述方法

import scipy
sample_rate, X = scipy.io.wavfile.read(wave_filename)

结果（将X单独绘制后，再运行上面图形，可以看出草绿色的就是背景）

附：梅尔频率倒谱系数（MFCC）
http://blog.csdn.net/zouxy09/article/details/9156785/