JaWavedit Frequently Asked Questions (May 1998)

 

Q 1: Which sound-quality does JaWavedit provide ?
Q 2: How can I get the Source code ?
Q 3: I'm interested in using JaWavedit on the Mac.
Q 4: Please cache files on disk, I want to use large files.
Q 5: The project looks promising but I can't even get it to run (only "File not found.")
Q 6: How did you get the idea to create JaWavedit ?

 

Q 1: Which sound-quality does JaWavedit provide ?
Does JaWavedit support a speaker-driver ?

A 1: The Problem about treating sound with Java is the lack of direct access to Windows functions and of course there is no direct hardware access.
You are limited to JavaÆs restrictions which are up to now quite strong:
8000Hz 8 bit mono and it only allows the standard uLaw format (ca. 12bit).
JaWavedit converts the internal audio files to 8000Hz while playing, and reduces the bit rate to uLaw format.
So speaker support is not possible û but JaWavedit will enhance as soon as Java provides the possibilities.
We hope that the JavaSound API will soon be available so that output will
be done with real quality, i.e. 16bit and 44100Hz.

Q 2: How can I get the source code ?

A 2:Generally we only give away for private/educational purposes, and only parts of the source code. So when we feel like it, we will send you some classes in that you're especially interested. Please let us know your choice (i.e. wave loading classes) along with a reason.
All this is because we would not like that people would just take our classes and sell the resulting program.

Additionally, we ask for a note on us in a program that significantly uses our classes. Also we're of course very interested in such a program.

Q 3: I'm interested in using JaWavedit on the Mac.
I notice that you only provide installation files for Suns and PCs.

A 3: We are asking all MAC users to find out how this might go. We don't have access to MACs and therefore could not do it ourselves and try it yet.

 

Q 4: Please cache files on disk, I want to use large files.

A 4: JaWavedit is indeed "wasting" memory. Especially, every file is converted to stereo, so that mono files take the double amount of memory. We have been thinking about that, too. But we wanted to provide a real easy way to write the JWModules. And, obviously, treating an array is the simplest way - rather than operating on a stream or something like that.
Right now we decided that the drawback of a filesize limit is less hard than to have the JWModules getting complicated.

Also, the objective of JaWavedit was not to have a full-featured professional Wave-Editor. Especially on Windows platforms probably never a Wave Editor in Java will reach the performance and power of a commercial Wave-Editor.

Instead, we wanted to provide a developpers tool, finally a free and convenient wave-editor for Unix platforms (which was missing in our opinion) and a general demonstration of Java's capabilities regarding sound.

With 48MB RAM I succeeded to load wave files up to 8 MB mono. I hope that you agree that this is not really "tiny". (OK, not suitable for whole songs)

 

Q 5: The project looks promising but I can't even get it to run.
I unzipped it into c:\jaWavedit but when I execute the bat file i get four 'file not found' comments, and nothing else. Please advise as I am very excited about playing with this program.

A 5: I guess that your JDK/JDR is not set up properly.
For Win32 OS there are two possibilities to provide the java environment (see dowloadpage for more details).
You should check these steps:

JDK:

  1. 1.: JDK Make sure you have installed JDK 1.1.3 or higher. Earlier versions are too buggy or (JDK 1.0.x) would not work at all. You can download the latest JDK somewhere at http://java.sun.com . Anyway, a re-installation of the JDK could help, too.
  2. Your java\bin directory should be in the PATH. This is a very common error, since the installation program of the JDK does not do this always. Simplest way to check this is to open a DOS box (command line) and to enter

  3. java [enter]
    It should appear a short description of java's command line parameters. If there is only a file not found error, you must add the bin directory manually to your PATH.
    In the following I refer to your JDK directory as "C:\jdk1.1.5".
    1. Windows 95

    2. Open the C:\autoexec.bat file into a Text-Editor (e.g. Notepad). Add as last line this:
      PATH=%PATH%;C:\jdk1.1.5\bin
    3. Windows NT

    4. In the Control Panel, select "System". There you select the tab "Environment". In the upper list select the variable "Path". In the Edit Box at the bottom ("Value"), add this to the existing PATH:
      ";C:\jdk1.1.5\bin". Don't add a blank before the semi-colon !

JRE:

  1. 1.: JDK Make sure you have installed JRE 1.1 or higher. Anyway, a re-installation could help, too.
  2. Your java\bin directory should be in the PATH. This is a very common error, since the installation program of the JDR does not do this always. Simplest way to check this is to open a DOS box (command line) and to enter

  3. jre [enter]
    It should appear a short description of the command line parameters. If there is only a file not found error, you must add the bin directory manually to your PATH.
    In the following I refer to your JDR directory as "C:\Program Files\JavaSoft\JRE\1.1".
    1. Windows 95

    2. Open the C:\autoexec.bat file into a Text-Editor (e.g. Notepad). Add as last line this:
      PATH=%PATH%;"C:\Program Files\JavaSoft\JRE\1.1\bin"
    3. Windows NT

    4. In the Control Panel, select "System". There you select the tab "Environment". In the upper list select the variable "Path". In the Edit Box at the bottom ("Value"), add this to the existing PATH:
      ";C:\Program Files\JavaSoft\JRE\1.1\bin". Don't add a blank before the semi-colon !

 

  1. Now your PATH should be set up properly and after a reboot, you should be able to run java from the command line - and JaWavedit should start...

Please see also the readme on the WebPage and in the distributed package.

 

Q 6: How did you get the idea to create JaWavedit ?

A 6: We are students of computer science and the programm was originally an university project, for which we care even after getting the (good:) grade.
Moreover we, especially Florian, are much into music with computer.