java 读取.wav文件(波形文件)并绘制波形图例子

因项目需要读取.wav文件（波形文件）并绘制波形图，因此简单的做了这方面的封装。


其实主要是对wav文件读取的封装，下面是一个wav文件读取器的封装：

[java] view plaincopyprint?

// filename: WaveFileReader.java
// RobinTang
// 2012-08-23

import java.io.*;


public class WaveFileReader {
private String filename = null;
private int[][] data = null;

private int len = 0;

private String chunkdescriptor = null;
static private int lenchunkdescriptor = 4;

private long chunksize = 0;
static private int lenchunksize = 4;

private String waveflag = null;
static private int lenwaveflag = 4;

private String fmtubchunk = null;
static private int lenfmtubchunk = 4;

private long subchunk1size = 0;
static private int lensubchunk1size = 4;

private int audioformat = 0;
static private int lenaudioformat = 2;

private int numchannels = 0;
static private int lennumchannels = 2;

private long samplerate = 0;
static private int lensamplerate = 2;

private long byterate = 0;
static private int lenbyterate = 4;

private int blockalign = 0;
static private int lenblockling = 2;

private int bitspersample = 0;
static private int lenbitspersample = 2;

private String datasubchunk = null;
static private int lendatasubchunk = 4;

private long subchunk2size = 0;
static private int lensubchunk2size = 4;


private FileInputStream fis = null;
private BufferedInputStream bis = null;

private boolean issuccess = false;

public WaveFileReader(String filename) {

this.initReader(filename);
}

// 判断是否创建wav读取器成功
public boolean isSuccess() {
return issuccess;
}

// 获取每个采样的编码长度，8bit或者16bit
public int getBitPerSample(){
return this.bitspersample;
}

// 获取采样率
public long getSampleRate(){
return this.samplerate;
}

// 获取声道个数，1代表单声道 2代表立体声
public int getNumChannels(){
return this.numchannels;
}

// 获取数据长度，也就是一共采样多少个
public int getDataLen(){
return this.len;
}

// 获取数据
// 数据是一个二维数组，[n][m]代表第n个声道的第m个采样值
public int[][] getData(){
return this.data;
}

private void initReader(String filename){
this.filename = filename;

try {
fis = new FileInputStream(this.filename);
bis = new BufferedInputStream(fis);

this.chunkdescriptor = readString(lenchunkdescriptor);
if(!chunkdescriptor.endsWith("RIFF"))
throw new IllegalArgumentException("RIFF miss, " + filename + " is not a wave file.");

this.chunksize = readLong();
this.waveflag = readString(lenwaveflag);
if(!waveflag.endsWith("WAVE"))
throw new IllegalArgumentException("WAVE miss, " + filename + " is not a wave file.");

this.fmtubchunk = readString(lenfmtubchunk);
if(!fmtubchunk.endsWith("fmt "))
throw new IllegalArgumentException("fmt miss, " + filename + " is not a wave file.");

this.subchunk1size = readLong();
this.audioformat = readInt();
this.numchannels = readInt();
this.samplerate = readLong();
this.byterate = readLong();
this.blockalign = readInt();
this.bitspersample = readInt();

this.datasubchunk = readString(lendatasubchunk);
if(!datasubchunk.endsWith("data"))
throw new IllegalArgumentException("data miss, " + filename + " is not a wave file.");
this.subchunk2size = readLong();

this.len = (int)(this.subchunk2size/(this.bitspersample/8)/this.numchannels);

this.data = new int[this.numchannels][this.len];

for(int i=0; ifor(int n=0; nif(this.bitspersample == 8){
this.data[n][i] = bis.read();
}
else if(this.bitspersample == 16){
this.data[n][i] = this.readInt();
}
}
}

issuccess = true;
} catch (Exception e) {
e.printStackTrace();
}
finally{
try{
if(bis != null)
bis.close();
if(fis != null)
fis.close();
}
catch(Exception e1){

e1.printStackTrace();
}
}
}

private String readString(int len){
byte[] buf = new byte[len];
try {
if(bis.read(buf)!=len)
throw new IOException("no more data!!!");
} catch (IOException e) {
e.printStackTrace();
}
return new String(buf);
}

private int readInt(){
byte[] buf = new byte[2];
int res = 0;
try {
if(bis.read(buf)!=2)
throw new IOException("no more data!!!");
res = (buf[0]&0x000000FF) | (((int)buf[1])<<8);
} catch (IOException e) {
e.printStackTrace();
}
return res;
}

private long readLong(){
long res = 0;
try {
long[] l = new long[4];
for(int i=0; i<4; ++i){
l[i] = bis.read();
if(l[i]==-1){
throw new IOException("no more data!!!");
}
}
res = l[0] | (l[1]<<8) | (l[2]<<16) | (l[3]<<24);
} catch (IOException e) {
e.printStackTrace();
}
return res;
}

private byte[] readBytes(int len){
byte[] buf = new byte[len];
try {
if(bis.read(buf)!=len)
throw new IOException("no more data!!!");
} catch (IOException e) {
e.printStackTrace();
}
return buf;
}
}


为了绘制波形，因此做了一个从JPanel教程而来的波形绘制面板：

[java] view plaincopyprint?

// filename: DrawPanel.java
// RobinTang
// 2012-08-23

import java.awt.Color;
import java.awt.Graphics;

import javax.swing.JPanel;


@SuppressWarnings("serial")
public class DrawPanel extends JPanel {
private int[] data = null;

public DrawPanel(int[] data) {
this.data = data;
}

@Override
protected void paintComponent(Graphics g) {
int ww = getWidth();
int hh = getHeight();
g.setColor(Color.WHITE);
g.fillRect(0, 0, ww, hh);

int len = data.length;
int step = len/ww;
if(step==0)
step = 1;

int prex = 0, prey = 0; //上一个坐标
int x = 0, y = 0;

g.setColor(Color.RED);
double k = hh/2.0/32768.0;

for(int i=0; ix = i;

// 下面是个三点取出并绘制
// 实际中应该按照采样率来设置间隔
y = hh-(int)(data[i*3]*k+hh/2);

System.out.print(y);
System.out.print(" ");

if(i!=0){
g.drawLine(x, y, prex, prey);
}
prex = x;
prey = y;
}
}
}


有了这些之后就可以调用绘制了，简单的：

[java] view plaincopyprint?

// WaveFileReadDemo.jave
// RobinTang
// 2012-08-23

import javax.swing.JFrame;


public class WaveFileReadDemo {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
String filename = "file.wav";
JFrame frame = new JFrame();
WaveFileReader reader = new WaveFileReader(filename);
if(reader.isSuccess()){
int[] data = reader.getData()[0]; //获取第一声道
DrawPanel drawPanel = new DrawPanel(data); // 创建一个绘制波形的面板
frame.add(drawPanel);
frame.setTitle(filename);
frame.setSize(800, 400);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
else{
System.err.println(filename + "不是一个正常的wav文件");
}
}
}


工程的源代码可以在我的百度网盘上找到，直接到开源JAVA

放上效果图一张：