DMX6fire / ice1712: Long initialization time for playback with Java

[Steffen Sauder <steffensauder@gmx.de>]

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Hello,

I am working on an audio-application with java 1.4, and I noticed that 
with the current alsa-release the time neccessary to initialize my 
Terratec DMX6fire card for playback (in oss emulation mode) increased a 
lot since older versions.

I wrote a small program to measure the time it takes for simply starting 
the playback of a wav/aiff file. I noticed that the 0.9.8 release uses a 
_lot_ more time on the AudioSystem.getMixerInfo() call (which searches 
for all available devices) than older versions. I also noticed that the 
times differ a lot for different JDKs, so here are the results for the 
sun-jdk-1.4.2.01, blackdown-jdk-1.4.1 and ibm-jdk-1.4.1 with the 
different alsa-driver versions.

alsa-driver 0.9.2 - 0.9.3a:
sun:  3.2- 3.3 sec     bdn:  1.9- 2.0 sec   ibm:  0.7- 0.8 sec

alsa-driver 0.9.3b - 0.9.7:
sun:  6.2- 6.3 sec     bdn: 13.7-13.8 sec   ibm:  3.7- 3.9 sec

alsa-driver 0.9.8:
sun: 48.0-48.5 sec     bdn: 24.7-24.8 sec   ibm: 13.7-13.8 sec

alsa-driver cvs-nov-02:
sun: 20.7-20.9 sec     bdn: 24.8-24.9 sec   ibm: 13.8-13.9 sec

So things got worse between 0.9.3a and .b (the same moment the 
mplayer-oss-emulation-delay problem occured!) and 0.9.7 and 0.9.8. 
Current CVS version is working a bit better for sun's jdk, but not for 
the others. I did not try different alsa-lib versions (used 0.9.2 all 
the time) - don't know if this would make any difference.

I attached the source code of the small programm, its syntax is:

java AudioTest AUDIOFILE [DEVICE_NO]

where DEVICE_NO is the index of the java-mixer-device to be used (they 
get listed if you start it without the second parameter)

Gruss,
Steffen

[-- Attachment #2: AudioTest.java --]
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import javax.sound.sampled.*;
/**
 *
 * @author  fali
 */
public class AudioTest {
  
  /** Creates a new instance of AudioTest */
  public AudioTest() {
  }
  
  private static void playAudioFile(String fileName, int device) throws UnsupportedAudioFileException, LineUnavailableException, java.io.IOException {
    long beginTime = System.currentTimeMillis();

    System.out.println("checking for available devices on this system...");
    Mixer.Info[] mixerInfos = AudioSystem.getMixerInfo();
    for (int i=0; i<mixerInfos.length; i++) {
      System.out.println(i+" "+mixerInfos[i].getName()+"\t"+mixerInfos[i].getVendor()); 
    }
    System.out.println();
    
    System.out.println("getting mixer device "+mixerInfos[device].getName()+"...");
    Mixer mixer = AudioSystem.getMixer(mixerInfos[device]);
    System.out.println("got mixer device, trying to open it...");
    mixer.open();
    System.out.println("mixer device opened, checking supported lines...");
    
    Line.Info[] supportedLines = mixer.getSourceLineInfo();
    for (int i=0; i<supportedLines.length; i++) {
      System.out.println(supportedLines[i].toString()); 
    }
    System.out.println();

    java.io.File file = new java.io.File(fileName);
    AudioInputStream audioInputStream = AudioSystem.getAudioInputStream(file);
    AudioFormat audioFormat = audioInputStream.getFormat();
    System.out.println("audio file opened, format is "+audioFormat.toString());
    
    Line.Info lineInfo = new DataLine.Info(SourceDataLine.class, audioFormat);
    System.out.println("obtaining SourceDataLine for that AudioFormat...");
    SourceDataLine sourceDataLine = (SourceDataLine)mixer.getLine(lineInfo);
    System.out.println("opening SourceDataLine...");
    sourceDataLine.open(audioFormat);
    System.out.println("starting SourceDataLine...");
    sourceDataLine.start();

    long endTime = System.currentTimeMillis();
    float seconds = (endTime-beginTime)/1000.0f;
    System.out.println("it took "+seconds+" seconds to start playback.");
    
    byte[] buf = new byte[1024];
    int bytesRead = 0;
    while(bytesRead>=0) {
      bytesRead = audioInputStream.read(buf);
      if (bytesRead>0) {
        sourceDataLine.write(buf, 0, bytesRead); 
      }
    }
    
    sourceDataLine.stop();
    sourceDataLine.close();
    audioInputStream.close();
    
  }
  
  public static void main(String[] args) {
    try {
      if (args.length==0) {
        System.err.println("first argument has to be an audio file.");
        System.exit(-1);
      }
      String fileName = args[0];
      int device = 0;
      if (args.length==2) {
        device = Integer.parseInt(args[1]); 
      }
      playAudioFile(fileName, device);
    } catch (Exception e) {
      e.printStackTrace(); 
    }
  }
  
}