java读取wav文件（波形文件）并绘制波形图的方法

本文实例讲述了java读取wav文件（波形文件）并绘制波形图的方法。分享给大家供大家参考。具体如下：

因为最近有不少网友询问我波形文件读写方面的问题，出于让大家更方便以及让代码能够得到更好的改进，我将这部分（波形文件的读写）代码开源在GitHub上面。

地址为https://github.com/sintrb/WaveAccess/，最新的代码、例子、文档都在那上面，我会在我时间精力允许的前提下对该项目进行维护，同时也希望对这方面有兴趣的网友能够加入到该开源项目上。

以下内容基本都过期了，你可以直接去GitHub上面阅读、下载该项目。

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：

// 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; i<this.len; ++i){
        for(int n=0; n<this.numchannels; ++n){
          if(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：

// 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; i<ww; ++i){
      x = 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：

// WaveFileReadDemo.java
// 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：

希望本文所述对大家的java程序设计有所帮助。