在Ubuntu上用Java定义AudioFormat

Question

我想知道如何定义Ubuntu上剪辑的音频格式。在Windows上，下面的代码可以工作，但在Ubuntu 14.10上却不行

import java.io.ByteArrayInputStream;
import java.nio.ByteBuffer;
import java.nio.ShortBuffer;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioFormat.Encoding;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.Clip;

class SongPlayer{    
    static int samplesPerSecond = 44100;

    // Plays back a raw audio buffer being passed.
    // @param song Raw signal of sound to be played. Amplitude in range [-1.0, 1.0]
    static void playSong(double[] song){
        AudioFormat format = new AudioFormat(
            Encoding.PCM_SIGNED,         // Encoding
            samplesPerSecond,            // sample rate
            Short.SIZE,                  // bits per sample
            1,                           // number of channels
            Short.SIZE / 8,              // bytes per frame
            samplesPerSecond,            // frame rate
            true);                       // big endian

        ByteBuffer buffer = ByteBuffer.allocate(song.length * (Short.SIZE / 8));
        ShortBuffer sb = buffer.asShortBuffer();
        for (double value : song){
            value = Math.max(-1.0,  Math.min(1.0, value));
            sb.put((short)(Short.MAX_VALUE * value));
        }

        AudioInputStream stream = new AudioInputStream(new ByteArrayInputStream(buffer.array()), format, song.length);

        try{
            Clip clip = AudioSystem.getClip();
            clip.open(stream);
            clip.start();
            Thread.sleep(1000 * 5);
            clip.drain();
        }catch (Exception e){
            e.printStackTrace();
            System.out.println("Playback failed!");
        }
    }

    public static void main(String[] args){
        double[] noise = new double[1000000];

        for(int i = 0; i < 1000000; i++){
            noise[i] = 2 * Math.random() - 1;
        }

        playSong(noise);
    }
}

错误消息如下所示：

    at org.classpath.icedtea.pulseaudio.PulseAudioDataLine.createStream(PulseAudioDataLine.java:142)
    at org.classpath.icedtea.pulseaudio.PulseAudioDataLine.open(PulseAudioDataLine.java:99)
    at org.classpath.icedtea.pulseaudio.PulseAudioDataLine.open(PulseAudioDataLine.java:283)
    at org.classpath.icedtea.pulseaudio.PulseAudioClip.open(PulseAudioClip.java:402)
    at org.classpath.icedtea.pulseaudio.PulseAudioClip.open(PulseAudioClip.java:453)
    at SongPlayer.playSong(song.java:39)
    at SongPlayer.main(song.java:56)
Playback failed!

通常，我会使用stream.getFormat()来获得格式，但在这种情况下，我想“播放一首歌”，随机数介于-1和1之间，这将导致随机噪声。我读过一些与类似问题有关的问题，但它们通常只想打开一个文件，而这是另一回事。感谢任何提供帮助的人

Answer 1

不要将IcedTea JRE用于您的程序。我从webupd8 ppa在ubuntu上用Oracle Java 8运行了您提供的代码；它是有效的。像安装Oracle Java 8一样安装

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer