[Audio-engine-dev] Re: Possible bugs

[Andreas Wenger]

Hi Karl,


gervill-0.8-fix1.jar fixed both problems.


Volume did not work, because I could only test Gervill with


 > sequencer = MidiSystem.getSequencer();
 > synthesizer = MidiSystem.getSynthesizer();


When using the now perfectly working

> sequencer = MidiSystem.getSequencer(false);
> synthesizer = MidiSystem.getSynthesizer();
> Transmitter seqTransmitter = sequencer.getTransmitter();
> seqTransmitter.setReceiver(synthesizer.getReceiver());


volume changes too (no idea why this is necessary, but it's the same
with old Java Sound. Perhaps anybody can tell me?
This is how I get the channels: MidiChannel[] channels = 
synthesizer.getChannels();)


BTW, another thing I don't understand is the following (but same
thing in old Java Sound).
Many sites tell me, that volume control is between 0 and 127, see e.g.
http://www.musicmarkup.info/midi/control.html

In fact I get max volume with 255, min with 0.

Here is my complete setVolume method.

>   /**
>    * Sets the volume.
>    * @param volume  value between 0 (silent) and 1 (loud)
>    */
>   public void setVolume(float volume)
>   {
>     this.volume = volume;
>     MidiChannel[] channels = synthesizer.getChannels();
>     
>     //TODO: should be 127 (some websites say this)
>     //but 255 is the real max volume!
>     int max = 255;
>     
>     for (int i = 0; i < channels.length; i++)
>     {
>       channels[i].controlChange(7, (int) (volume * max));
>     }
>   }

Did I already mention that Gervill is just GREAT?!
Keep on your brilliant work! :-)


Andi




Karl Helgason schrieb:
> Hi,
>   
> First:
>
> I can confirm this is a bug.
>
> Calling getReceiver before opening the synthesizer results in NullPointerException.
> This is not supposed to happen. Thanks for noticing this.
>
> Second:
>
> I tried our way to change volume, and it does work with Gervill.
> Please explain better how it failed.
>
> I uploaded updated version of gervill with this bug fixed:
> Please download "gervill-0.8-fix1.jar" from:
>    https://gervill.dev.java.net/servlets/ProjectDocumentList?folderID=0
> and let me know how this works.
>
> regards,
> Karl
>
> ________________________________________
> Frá: audio-engine-dev-bounces at openjdk.java.net [audio-engine-dev-bounces at openjdk.java.net] Fyrir h&#246;nd Andreas Wenger [info at xenoage.com]
> Sent: 6. febrúar 2008 17:08
> Viðtakandi: audio-engine-dev at openjdk.java.net
> Efni: [Audio-engine-dev]  Possible bugs
>
> Hi,
>
>
> I'm no experienced Java Sound user, so please forgive me if the following
> "bugs" are not caused by Gervill but my own program.
>
> I tried to integrate Gervill into my program Xenoage Player, which
> is a free MIDI player for MusicXML files, http://www.xenoage.com/player/
>
>
> First:
>
> This works:
>   
>> sequencer = MidiSystem.getSequencer();
>> synthesizer = MidiSystem.getSynthesizer();
>>     
> But this fails (works perfectly with old Java Sound):
>
>   
>> sequencer = MidiSystem.getSequencer(false);
>> synthesizer = MidiSystem.getSynthesizer();
>> Transmitter seqTransmitter = sequencer.getTransmitter();
>> seqTransmitter.setReceiver(synthesizer.getReceiver());
>>     
> with
>   
>> java.lang.NullPointerException
>>     at com.sun.media.sound.SoftReceiver.<init>(Unknown Source)
>>     at com.sun.media.sound.SoftSynthesizer.getReceiver(Unknown Source)
>>     at com.xenoage.player.Player.<init>(Player.java:79)
>>     
> Line 79 is "seqTransmitter.setReceiver(synthesizer.getReceiver());"
>
>
> Second:
>
> This is the way I change the playback volume (maybe this is bad code,
> but it was the only way it worked for me with old Java Sound):
>
>   
>> MidiChannel[] channels = synthesizer.getChannels();
>> //...
>> for (int i = 0; i < channels.length; i++)
>> {
>>   channels[i].controlChange(7, (int) (volume * max));
>> }
>>     
> This doesn't change the volume, while old Java Sound does.
>
>
> If it helps, code is available by SVN, see the website.
> If these are no bugs, please forgive me ;-)
>
> Bye,
>
>
> Andi
>
>
>
>
>
> _______________________________________________
> audio-engine-dev mailing list
> audio-engine-dev at openjdk.java.net
> http://mail.openjdk.java.net/mailman/listinfo/audio-engine-dev
>
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.5.516 / Virus Database: 269.19.20/1261 - Release Date: 5.2.2008 20:57
>
>