Thread: how to make my code play some audio?Just a bit!

Originally Posted by Samaras

...
So what i need is to just make a single 'beep' in my program...

If you have a speaker on your system and just want to make it beep, you can try the following:

        System.out.println('\007');

I'm talking about an old-fashioned "raw" speaker here, not a sound system attached to a sound card or motherboard sound card circuitry.

Anyhow...

It might or might not work, depending on your computer's setup.

The '\007' character is ASCII BEL, which used to make the bell on a Teletype machine go "ding" so that an operator could know an important message had arrived (in case the rattling of the machine's mechanical print mechanism hadn't awakened him from his slumber).

My Windows XP machine and my Centos 5.8 workstations (and lots of other PC operating system setups) don't have bells, but they cause a single "Beep" (a single audio tone with duration of a small number of hundreds of milliseconds) to be emitted from the speaker when you send this character to the standard output data stream.

Potential problems:

1. This is not part of any Java (or any other language) standard. It might or might not work with your machine
   
   
2. Not all of my workstations have speakers. Interestingly, some of them have sound cards, and there might (or, maybe, not) be ways to set things up so that a system "beep" goes through the sound card. I won't get into this, since it won't add to anyone's Java learning experience.
   
   
3. There is no way to control the frequency or duration (or any other characteristics) of the "beep." You get what you get (or not).

Originally Posted by Samaras

have no idea about audio and code

Now, if you don't know about sound and Java, you can look for tutorials. None of them will be about a single simple "beep" through the speaker. They will be about how to use some kind if audio API to get Java to emit audio through a sound card. They might be about reading a file and playing music, but you can read an audio .wav file in which a "beep" has been encoded and play it through your sound card also.

When I started Java a couple of months ago I didn't have audio in mind, but I became interested (a little), so I looked at a couple of places:

In addition to the well-traveled Java Tutorial Sound Trail, I found jsresources.

There is a Simple Audio Player example that gives a complete program (using the javax.sound.sampled package) for playing an audio .wav file. On my Linux systems there are a number of "beep" audio .wav files in the /usr/share/sounds directory. I just played KDE_Beep_Beep.wav with this application and got something from my sound card that sounds like a beep. On my Windows XP machine there is a folder, C:\Windows\Media, that has lots of system .wav files. I don't see a beep (I didn't look very hard), but there is a "ding" and a "chord" and other .wav files that can be played with the Simple Audio Player that I reference above.

Now, it might happen that the Simple Audio Player doesn't work "out of the box" on your system. There is a lot (a lot) of information on that site that might help. Sometimes if you want things to happen, you have to work for it. For example, that application uses settings already present in your sound system. The program doesn't set the volume. If sound is muted, this program won't turn it on. If you have more than one sound channel, it uses whatever has previously been set. Etc. There are ways to make different things happen, but just getting something out of the sound card will be a start, right?

The next step might be to generate sampled data values to feed to the audio stream instead of having to read from a file. For something like a simple sinusoid, it's not too difficult to create a sequence of samples "on the fly" rather than relying on a pre-recorded file. This is an additional learning opportunity.

Originally Posted by Samaras

Maybe i am not ready for this

Well, what are you ready for? Learning about Java? Learning about audio? Learning about Java audio API's? What? I mean, no one was born knowing this stuff.

The program that I referenced above has something like ninety lines of Java (after you get rid of all of those pesky copyright notices and the excellent javadoc stuff and other meaningful comments), and a lot of the code is concerned with exception handling rather than the relatively few lines needed to actually set things up to make sounds. I like that particular application as a learning vehicle since it doesn't use any special packages other than what is supplied with "standard" Java installations. Maybe it's a place to start. (If you are doing Android development, there's an entire media interface that does everything, but that's another story.)

If anyone needs a .wav file to practice on, I have attached one that might be appropriate for August 25, 2012. (You have to unzip it, obviously.) The clip is from NASA and contains immortal words from a man who also said, "I am, and ever will be, a white-socks, pocket-protector, nerdy engineer."


Cheers,

Z

Originally Posted by Samaras

 System.out.println('\007');

did not work.

Well, I said that it might not make a beep. I am, however surprised that you got a square printed out.

Here's what I did:
created the following in a file named Z.java:

public class Z
{
    public static void main(String [] args)
    {
        System.out.println('\007');
    }
}

Compiled from a command line:

javac Z.java

Executed with a command line:

java Z

Nothing appeared in the command window, and I got a little "beep" from the built-in speaker (not through the sound card).

My setup: Windows XP, Service Pack 3
java and javac version 1.6.0_33

Paste the code from this post into your editor (don't retype). Compile and execute from a command line. Do you still get a "square" printed out?

Maybe it's a language environment thing. Perhaps you can try '\u0007' instead of '\007' in the println() statement.


What happens if you echo Ctrl-G from a command line:

Enter

ECHO ^G

Where ^G means hold the Ctrl key down while pressing the G key. (Reference Wikipedia - Bell Character)

Cheers!

Z

Originally Posted by Samaras

I do not know how to handle java files from cmd.I use netbeans.

The Netbeans terminal emulator does not work very well with control characters (and, in particular doesn't work with '\007'). That's one reason I always start with command line programs and I always recommend that other people do it also if they expect consistent help from me. I really think that beginners shouldn't be isolated from underlying hardware and operating system functions.

However, be that as it may...

I tested the following procedure with Netbeans 7.0.1 on my Linux workstation. Let me know if it works on your system. (I don't have and don't intend to install Netbeans on my Windows box.)

I made a new Netbeans project. I called it SpeakerBeep.

Netbeans opened an editor window as SpeakerBeep.java.

I left the package speakerbeep; statement in place and erased everything else and entered the simplest program that I could think of that plays a beep through the speaker from the Netbeans IDE (i.e. without depending directly on standard output through a terminal):

Now SpeakerBeep.java looks like this:

package speakerbeep;
import java.awt.*;
 
public class SpeakerBeep {
    public static void main(String [] args) {
        Toolkit.getDefaultToolkit().beep();
    }
}

I made SpeakerBeep the Main project and compiled. There were no errors.

When I hit the Run icon, I got a beep from the speaker.


In order to use the SimpleAudioPlayer source code from the jsresources link my earlier post, you can try the following:

Create a new Netbeans project named SimpleAudioPlayer. It opens an edit window as SimpleAudioPlayer.java

Leave the package simpleaudioplayer; statement in place and erase everything else. Paste SimpleAudioPlayer.java from the jsresources link into the edit window below the package statement. Make SimpleAudioPlayer the Main project and build the project. You should not get any errors.

Now, you can change the statement where it gets the name of the file from a command line argument to a statement that it assigns the filename to a String that you define (give complete path/file name of a .wav file).

Or...

Set the project command line argument to the full path name of a .wav file (From Run menu, select Set Project Configuration->Customize... and fill in the "Arguments" box with the complete path/file name of a .wav file.)

If you made changes, build the project again and make sure there are no errors.

Then...

Click the Run icon.

When I did this on my system, the .wav file played through my sound card.

IWFMYMMV. (It Works For Me; Your Mileage May Vary.)

Cheers!

Z

As mentioned in the javadoc comments for SimpleAudioPlayer: "Only PCM encoded files are supported. A-law, μ-law, ADPCM, ogg vorbis, mp3 and other compressed data formats are not supported." Many downloaded .wav files designed as ringtones or answer messages (including your hideous rappin.wav) are compressed with mp3. That's right, even though it is a .wav file, the audio data samples are encoded like an mp3 file. Won't work with SimpleAudioPlayer. Period.

The jsresources web site has a FAQ and various places where they talk about Tritonus Plugin for Java JDK They also have an AudioPlayer example (that's AudioPlayer, not SimpleAudioPlayer) application that they say will handle mp3-encoded files. I haven't tried it and I probably won't, so feel free to experiment on your own.


Cheers!


Z