Hallo allerseits,
Ich bin jetzt schon seit einiger Zeit dabei, einen mp3 Player in Java zu realisieren. Abspielen tut er schon lange brav, und pausieren geht auch schon gut. Aber mein derzeitiges Hauptproblem, dass ich bis jetzt noch nicht gelöst bekommen habe ist, wie man in einer .mp3 Datei richtig skippt. Leider kann ich euch nicht sagen, wo das Problem in untigem SourceCode liegt (Methode seek). Ihr müsst mir den Code nicht verbessern, ein Hinweis genügt schon
.
btw: Es handelt sich um dieses Projekt:
https://github.com/s4ke/pure_mp3/wiki
Noch etwas:
Ich habe jetzt schon seit längerem das Gefühl, dass in der aktuellen OpenJDK in der Klasse SourceDataLine etwas schief läuft. Und zwar gibt die Methode Namens getMicroSecondsPosition() Millisekunden zurück (zumindest bei mir).
Hier der dazugehörige Bug bei launchpad:
https://bugs.launchpad.net/ubuntu/+source/openjdk-6/+bug/740485
Könntet ihr das mal prüfen?
Grüße
s4ke
Ich bin jetzt schon seit einiger Zeit dabei, einen mp3 Player in Java zu realisieren. Abspielen tut er schon lange brav, und pausieren geht auch schon gut. Aber mein derzeitiges Hauptproblem, dass ich bis jetzt noch nicht gelöst bekommen habe ist, wie man in einer .mp3 Datei richtig skippt. Leider kann ich euch nicht sagen, wo das Problem in untigem SourceCode liegt (Methode seek). Ihr müsst mir den Code nicht verbessern, ein Hinweis genügt schon
.btw: Es handelt sich um dieses Projekt:
https://github.com/s4ke/pure_mp3/wiki
Noch etwas:
Ich habe jetzt schon seit längerem das Gefühl, dass in der aktuellen OpenJDK in der Klasse SourceDataLine etwas schief läuft. Und zwar gibt die Methode Namens getMicroSecondsPosition() Millisekunden zurück (zumindest bei mir).
Hier der dazugehörige Bug bei launchpad:
https://bugs.launchpad.net/ubuntu/+source/openjdk-6/+bug/740485
Könntet ihr das mal prüfen?
Java:
/**
* @author Martin Braun
* MusicPlayer inspired by Matthias Pfisterer's examples on JavaSound
* (jsresources.org). Because of the fact, that this Software is meant
* to be Open-Source and I don't want to get anybody angry about me
* using parts of his intelligence without mentioning it, I hereby
* mention him as inspiration, because his code helped me to write this class.
*
* This file is part of pure.mp3.
*
* pure.mp3 is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* pure.mp3 is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with pure.mp3. If not, see <http://www.gnu.org/licenses/>.
*/
package pure_mp3;
//import java.net.URL;
import java.io.File;
import java.io.IOException;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.SourceDataLine;
import javax.sound.sampled.FloatControl;
public class StreamMusicPlayer extends Thread implements MusicPlayer
{
private static final int EXTERNAL_BUFFER_SIZE = 128000;
private AudioInputStream audioInputStream;
private SourceDataLine line;
private AudioFormat audioFormat;
private DataLine.Info info;
private Player player;
private Song song;
private boolean playing;
private long skippedDurationInMicroSeconds;
private int skippedFrames;
// private long position;
// private boolean skippingAllowed;
// private boolean running = false;
private boolean pause = false;
private boolean stop = false;
// private static boolean lineAvailable = true;
public StreamMusicPlayer(Song xSong, Player xPlayer)
{
super();
// position = 0;
player = xPlayer;
song = xSong;
try
{
insert(song);
}
catch(Exception e)
{
System.out.println("Error while inserting the file");
// player.next();
}
}
public void insert(Song song)
{
try
{
audioInputStream = AudioSystem.getAudioInputStream(song.getSource());
}
catch (Exception e)
{
System.out.println("Error while parsing URL to File/Stream");
// stop = true;
// player.stop();
// player.next();
}
if (audioInputStream != null)
{
AudioFormat format = audioInputStream.getFormat();
if ( format.getEncoding() != AudioFormat.Encoding.PCM_SIGNED )
{
AudioFormat newFormat = new AudioFormat(
AudioFormat.Encoding.PCM_SIGNED,
format.getSampleRate(),
16,
format.getChannels(),
format.getChannels() * 2,
format.getSampleRate(),
false );
AudioInputStream newStream = AudioSystem.getAudioInputStream( newFormat, audioInputStream );
format = newFormat;
audioInputStream = newStream;
}
}
audioFormat = audioInputStream.getFormat();
info = new DataLine.Info(SourceDataLine.class,audioFormat);
}
public void run()
{
// running = true;
try
{
line = (SourceDataLine) AudioSystem.getLine(info);
line.open(audioFormat);
line.start();
}
catch(LineUnavailableException e)
{
System.out.println(e.getMessage());
System.out.println("Line unavailable");
}
catch(Exception e)
{
System.out.println("Error while starting playback");
}
int nBytesRead = 0;
int bufferSize = EXTERNAL_BUFFER_SIZE;
if(audioFormat != null)
{
bufferSize = (int) audioFormat.getSampleRate() * audioFormat.getFrameSize();
System.out.println(audioFormat);
}
byte[] abData = new byte[bufferSize];
System.out.println("Buffer Size: " + bufferSize);
if(line != null)
{
setVolume(Global.VOLUME);
}
while (nBytesRead != -1 && !stop && line != null)
{
synchronized(this)
{
while (pause && !stop)
{
try
{
System.out.println("paused");
wait();
}
catch(Exception e)
{
}
}
notify();
}
if(!stop)
{
try
{
nBytesRead = audioInputStream.read(abData, 0, abData.length);
// position = position + nBytesRead;
}
catch (IOException e)
{
nBytesRead = -1;
}
if(nBytesRead != -1);
{
try
{
line.write(abData, 0, nBytesRead);
}
catch(IllegalArgumentException e)
{
//Has to be caught, because if the stream ends, there may occur an error,
//that the amount of bytes read is not valid (occurred under OpenJDK).
}
}
}
}
if(line != null)
{
line.drain();
line.close();
}
// running = false;
if(!stop)
{
player.playNext();
}
}
@Override
public synchronized void pause()
{
pause = !pause;
if(!pause)
System.out.println("Weiter Geht's!");
notify();
}
@Override
public synchronized void stop_()
{
stop = true;
notify();
}
@Override
public synchronized boolean isStopped()
{
return stop;
}
public synchronized boolean isPlaying()
{
return playing;
}
@Override
public void setVolume(float xVolume)
{
Global.setVolume(xVolume);
if(line.isControlSupported(FloatControl.Type.MASTER_GAIN))
{
xVolume = xVolume/100;
FloatControl volume = (FloatControl) line.getControl( FloatControl.Type.MASTER_GAIN);
double minGainDB = volume.getMinimum();
double ampGainDB = ((10.0f/20.0f)*volume.getMaximum())-volume.getMinimum();
double valueDB = minGainDB + (1/Global.LINEARSCALAR)*Math.log(1+(Math.exp(Global.LINEARSCALAR*ampGainDB)-1)*xVolume);
volume.setValue((float) valueDB);
}
else if( line.isControlSupported(FloatControl.Type.VOLUME))
{
FloatControl volume = (FloatControl) line.getControl( FloatControl.Type.VOLUME);
float onePercent = volume.getMaximum()/100;
volume.setValue(xVolume*onePercent);
}
}
@Override
public long getMicrosecondPosition()
{
return line.getMicrosecondPosition() + (skippedDurationInMicroSeconds/1000);
}
public int getFramePosition()
{
if(line != null)
{
return line.getFramePosition()+skippedFrames;
}
else
{
return 0;
}
}
public AudioFormat getAudioFormat()
{
return audioFormat;
}
// public long getPosition()
// {
// return position;
// }
public AudioInputStream getAudioInputStream()
{
return audioInputStream;
}
public Song getCurrentSong()
{
return song;
}
public void seek(int percentage)
{
// just pause the playback
pause();
try
{
File file = null;
try
{
file = new File(song.getSource().toURI());
}
catch(Exception e)
{
file = new File(song.getSource().getPath());
}
if(file != null)
{
long durationInSeconds = getDurationInSeconds();
double skippedPercentage = (double)percentage/100;
long skippedDurationInSeconds = (long) (durationInSeconds * skippedPercentage);
long bytesToSkip = (long)((skippedDurationInSeconds)*(double)(audioFormat.getSampleRate()*audioFormat.getFrameSize()));
System.out.println("Length in Bytes: " + (durationInSeconds)*((long)audioFormat.getSampleRate())*audioFormat.getFrameSize());
System.out.println("Bytes to Skip: " + bytesToSkip);
long bytesSkipped = audioInputStream.skip(bytesToSkip);
System.out.println("Bytes Skipped: " + bytesSkipped);
skippedFrames = skippedFrames + (int) bytesSkipped/audioFormat.getFrameSize();
System.out.println("Frame Length: " + getFrameLength());
System.out.println("Frames Skipped: " + skippedFrames);
}
}
catch (IOException e)
{
e.printStackTrace();
}
catch(Exception e)
{
e.printStackTrace();
}
// start playing again
pause();
}
public int getFrameLength()
{
// if(stop)
// {
// return -1;
// }
try
{
int durationInSeconds = getDurationInSeconds();
if(durationInSeconds > 0)
{
return (int)(durationInSeconds)*((int)audioFormat.getSampleRate());
}
return -1;
}
catch(Exception e)
{
System.out.println("Some other bug!");
return -1;
}
}
public int getDurationInSeconds()
{
return song.getDurationInSeconds();
}
}Grüße
s4ke
