Re: Java Audio Help (Mixers and Ports)

KWhat4 wrote:


I don't know if you are a C programmer or not but there is an
incongruity between C and Java naming in the audio business. In Java
Ports are used to get controls, like volume and frame etc. Lines are
used to capture or play audio data. SourceDataLines play,
TargetDataLines capture. Mixers are really complicated as they can have
Ports, SDLs and TDLs associated with them but may not.

Below is a simple example that gets audio data from a URL and plays it
by sending it to a SourceDataLine. See the comments in the source for
details.

Below that is a Sun program to list the ports on your computer. I'm
sorry it is formatted so poorly but that is the way it is.

import javax.sound.sampled.*;
import java.io.*;
import java.net.*;

public class AudioExample {
     public static void main(String[] args) throws Exception {
         // get all the mixers
         Mixer.Info[] mixInfo = AudioSystem.getMixerInfo();
         System.out.println("Mixers");
         for (int i=0; i<mixInfo.length; i++)
             System.out.println(" " + mixInfo[i].toString());

         // this is just source data, you can use whatever here
         // this file is from JavaSound, it is over 400k so might
         // take a while to download
         URL url = new URL("http://www.knutejohnson.com/22-new.aif");
         AudioInputStream ais = AudioSystem.getAudioInputStream(url);

         // format will probably be determined by source as in this case
         AudioFormat af = ais.getFormat();
         System.out.println(af.toString());

         // get a SDL with specified format from specified mixer
         SourceDataLine sdl = AudioSystem.getSourceDataLine(af,mixInfo[0]);

         // open requires the format too
         sdl.open(af);
         // no sound until SDL is started
         sdl.start();

         // read and write
         byte[] buf = new byte[1024];
         int bytesRead;
         while ((bytesRead = ais.read(buf)) != -1)
             sdl.write(buf,0,bytesRead);

         ais.close();

         // empty the buffer
         sdl.drain();
         // stop the line
         sdl.stop();
         // close it cause we're done
         sdl.close();
     }
}

/*
  * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
  *
  * Sun grants you ("Licensee") a non-exclusive, royalty free, license to
  use, * modify and redistribute this software in source and binary code
  form, * provided that i) this copyright notice and license appear on all
  copies of * the software; and ii) Licensee does not utilize the software
  in a manner * which is disparaging to Sun. * * This software is provided
  "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED
  CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY * IMPLIED
  WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR *
  NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE
  * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING,
  MODIFYING * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT
  WILL SUN OR ITS * LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR
  DATA, OR FOR DIRECT, * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR
  PUNITIVE DAMAGES, HOWEVER * CAUSED AND REGARDLESS OF THE THEORY OF
  LIABILITY, ARISING OUT OF THE USE OF * OR INABILITY TO USE SOFTWARE, EVEN
  IF SUN HAS BEEN ADVISED OF THE * POSSIBILITY OF SUCH DAMAGES. * * This
  software is not designed or intended for use in on-line control of *
  aircraft, air traffic, aircraft navigation or aircraft communications; or
  in * the design, construction, operation or maintenance of any nuclear *
  facility. Licensee represents and warrants that it will not use or *
  redistribute the Software for such purposes. */

import javax.sound.sampled.*;

public class ListPorts {
  public static void main(String[] args) {
   Mixer.Info[] aInfos = AudioSystem.getMixerInfo();
   for (int i = 0; i < aInfos.length; i++) {
    try {
     Mixer mixer = AudioSystem.getMixer(aInfos[i]);
     mixer.open();
     try {
      System.out.println(aInfos[i]);
      printPorts(mixer, mixer.getSourceLineInfo());
      printPorts(mixer, mixer.getTargetLineInfo());
     } finally {
      mixer.close();
     }
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
   if (aInfos.length == 0) {
    System.out.println("[No mixers available]");
   }
   System.exit(0);
  }

  public static void printPorts(Mixer mixer, Line.Info[] infos) {
   for (int i = 0; i<infos.length; i++) {
    try {
     if (infos[i] instanceof Port.Info) {
      Port.Info info = (Port.Info) infos[i];
      System.out.println(" Port "+info);
      Port port = (Port) mixer.getLine(info);
      port.open();
      try {
       printControls(port.getControls());
      } finally {
       port.close();
      }
     }
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  }

  public static void printControls(Control[] controls) {
   for (int i = 0; i<controls.length; i++) {
    printControl(" ", "Controls["+i+"]: ", controls[i]);
   }
   if (controls.length == 0) {
    System.out.println(" [no controls]");
   }

  }

  static boolean balanceTested = false;

  public static void printControl(String indent, String id, Control
  control) {
   if (control instanceof BooleanControl) {
    BooleanControl ctrl = (BooleanControl) control;
    System.out.println(indent+id+"BooleanControl: "+ctrl);
    //try {
    // Thread.sleep(500);
    // ctrl.setValue(!ctrl.getValue());
    // Thread.sleep(500);
    // ctrl.setValue(!ctrl.getValue());
    //} catch (Exception e) {}
   }
   else if (control instanceof CompoundControl) {
    CompoundControl ctrl = (CompoundControl) control;
    Control[] ctrls = ctrl.getMemberControls();
    System.out.println(indent+id+"CompoundControl: "+control);
    for (int i=0; i<ctrls.length; i++) {
     printControl(indent+" ", "MemberControls["+i+"]: ", ctrls[i]);
    }
   }
   else if (control instanceof EnumControl) {
    EnumControl ctrl = (EnumControl) control;
    Object[] values = ctrl.getValues();
    Object value = ctrl.getValue();
    System.out.println(indent+id+"EnumControl: "+control);
    for (int i=0; i<values.length; i++) {
     if (values[i] instanceof Control) {
      printControl(indent+" ", "Values["+i+"]:"+
       ((values[i]==value)?"*":""), (Control) values[i]);
     } else {
      System.out.println(indent+" Values["+i+"]:"+
       ((values[i]==value)?"*":"")+values[i]);
     }
    }
   }
   else if (control instanceof FloatControl) {
    FloatControl ctrl = (FloatControl) control;
    System.out.println(indent+id+"FloatControl: "+ctrl);
    //try {
    // Thread.sleep(500);
    // float x = ctrl.getValue();
    // ctrl.setValue((float) (Math.random()*(ctrl.getMaximum() -
    // ctrl.getMinimum()) + ctrl.getMinimum())); // Thread.sleep(1000);
    // ctrl.setValue(x); //} catch (Exception e) {} //if (ctrl.getType() ==
    // FloatControl.Type.BALANCE && !balanceTested) {
    // balanceTested = true;
    // for (float y = -1.0f; y<=1.0f; y+=0.02) { // ctrl.setValue(y);
    // System.out.println(" Set to "+y);
    // System.out.println(" res"+ctrl.getValue()); // } //}
   } else {
    System.out.println(indent+id+"Control: "+control);
   }
  }
}

--

Knute Johnson
email s/nospam/knute/