使用Java混音(不使用混音器API)

我试图混合几个不同的音频流,并尝试让它们同时播放,而不是一次一个.

下面的代码一次一个地播放它们,我无法找到不使用Java Mixer API的解决方案.不幸的是,我的声卡不支持使用Mixer API进行同步,我不得不想办法通过代码来实现.

请指教.

/////代码如下////

class MixerProgram {
public static AudioFormat monoFormat;
private JFileChooser fileChooser = new JFileChooser(); 
private static File[] files;
private int trackCount;   
private FileInputStream[] fileStreams = new FileInputStream[trackCount];
public static AudioInputStream[] audioInputStream;
private Thread trackThread[] = new Thread[trackCount];
private static DataLine.Info sourceDataLineInfo = null; 
private static SourceDataLine[] sourceLine;  

public MixerProgram(String[] s)
{
  trackCount = s.length;
  sourceLine = new SourceDataLine[trackCount];
  audioInputStream = new AudioInputStream[trackCount]; 
  files = new File[s.length];
}

public static void getFiles(String[] s)
{
  files = new File[s.length];
  for(int i=0; i<s.length;i++)
  {
    File f = new File(s[i]);
    if (!f.exists()) 
    System.err.println("Wave file not found: " + filename);
    files[i] = f;
  }
}


public static void loadAudioFiles(String[] s) 
{
  AudioInputStream in = null;
  audioInputStream = new AudioInputStream[s.length];
  sourceLine = new SourceDataLine[s.length];
  for(int i=0;i<s.length;i++){
    try 
    {
      in = AudioSystem.getAudioInputStream(files[i]); 
    } 
    catch(Exception e) 
    {
      System.err.println("Failed to assign audioInputStream");
    }
    monoFormat = in.getFormat();
    AudioFormat decodedFormat = new AudioFormat(
                                              AudioFormat.Encoding.PCM_SIGNED,
                                              monoFormat.getSampleRate(), 16, monoFormat.getChannels(),
                                              monoFormat.getChannels() * 2, monoFormat.getSampleRate(),
                                              false);
  monoFormat = decodedFormat; //give back name
  audioInputStream[i] = AudioSystem.getAudioInputStream(decodedFormat, in);
  sourceDataLineInfo = new DataLine.Info(SourceDataLine.class, monoFormat);
  try 
  {
    sourceLine[i] = (SourceDataLine) AudioSystem.getLine(sourceDataLineInfo); 
    sourceLine[i].open(monoFormat);
  } 
  catch(LineUnavailableException e) 
  {
    System.err.println("Failed to get SourceDataLine" + e);
  }
}               
}

public static void playAudioMix(String[] s)
{
  final int tracks = s.length;
  System.out.println(tracks);
  Runnable playAudioMixRunner = new Runnable()
  {
    int bufferSize = (int) monoFormat.getSampleRate() * monoFormat.getFrameSize();
    byte[] buffer = new byte[bufferSize]; 
    public void run()
    {
      if(tracks==0)
        return;
      for(int i = 0; i < tracks; i++)
      {
        sourceLine[i].start();
      }        
      int bytesRead = 0;
      while(bytesRead != -1)
      {
        for(int i = 0; i < tracks; i++)
        {
          try 
          {
            bytesRead = audioInputStream[i].read(buffer, 0, buffer.length);
          } 
          catch (IOException e) {
          // TODO Auto-generated catch block
            e.printStackTrace();
          }            
          if(bytesRead >= 0)
          {
            int bytesWritten = sourceLine[i].write(buffer, 0, bytesRead);
            System.out.println(bytesWritten);
          }
        }
      }
    }
  };
  Thread playThread = new Thread(playAudioMixRunner);
  playThread.start();
}
}

解决方法:

问题是您没有将样本添加到一起.如果我们查看4个轨道,16位PCM数据,您需要将所有不同的值一起添加到一个最终输出中“混合”它们.因此,从纯数字的角度来看,它看起来像这样：

[Track1]  320  -16  2000   200  400
[Track2]   16    8   123   -87   91
[Track3]  -16  -34  -356  1200  805
[Track4] 1011 1230 -1230  -100   19
[Final!] 1331 1188   537  1213 1315

在上面的代码中,您应该只编写单个字节数组.该字节数组是加在一起的所有轨道的最终组合.问题是你正在为每个不同的轨道写一个字节数组(所以没有发生混音,正如你所观察到的那样).

如果你想保证你没有任何“剪辑”,你应该取所有曲目的平均值(所以添加上面的所有四个曲目并除以4).但是,选择这种方法会有一些瑕疵(例如,如果你在三个音轨和一个响亮的音轨上保持沉默,最终的输出将比一个非静音音轨的音量更安静).您可以使用更复杂的算法进行混音,但到那时您正在编写自己的混音器：P.

标签：mixer,java,audio,mixing,streaming
来源： https://codeday.me/bug/20190903/1797452.html