G4G0-1/Semester 1/Programming 1/Java/examples/projects/JLayer1.0.1

 JLayer 1.0.1

 JavaZOOM 1999-2008



 Project Homepage :

   http://www.javazoom.net/javalayer/javalayer.html 



 JAVA and MP3 online Forums :

   http://www.javazoom.net/services/forums/index.jsp

-----------------------------------------------------



DESCRIPTION :

-----------

JLayer is a library that decodes/plays/converts MPEG 1/2/2.5 Layer 1/2/3

(i.e. MP3) in real time for the JAVA(tm) platform. This is a non-commercial project 

and anyone can add his contribution. JLayer is licensed under LGPL (see LICENSE.txt).





FAQ : 

---



- How to install JLayer ?

  Before running JLayer you must set PATH and CLASSPATH for JAVA

  and you must add jl1.0.1.jar to the CLASSPATH.



- Do I need JMF to run JLayer player ?

  No, JMF is not required. You just need a JVM JavaSound 1.0 compliant.

  (i.e. JVM1.3 or higher).



- How to run the MP3TOWAV converter ?

  java javazoom.jl.converter.jlc -v -p output.wav yourfile.mp3

  (Note : MP3TOWAV converter should work under jdk1.1.x or higher)



- How to run the simple MP3 player ?

  java javazoom.jl.player.jlp localfile.mp3

   or

  java javazoom.jl.player.jlp -url http://www.aserver.com/remotefile.mp3

  Note : MP3 simple player only works under JVM that supports JavaSound 1.0 (i.e JDK1.3.x+)



- How to run the advanced (threaded) MP3 player ?

  java javazoom.jl.player.advanced.jlap localfile.mp3



- Does simple MP3 player support streaming ?

  Yes, use the following command to play music from stream :

  java javazoom.jl.player.jlp -url http://www.shoutcastserver.com:8000

  (If JLayer returns without playing SHOUTcast stream then it might mean 

   that the server expect a winamp like "User-Agent" in HTTP request).



- Does JLayer support MPEG 2.5 ?

  Yes, it works fine for all files generated with LAME.



- Does JLayer support VBR ?

  Yes, It supports VBRI and XING VBR header too. 



- How to get ID3v1 or ID3v2 tags from JLayer API ?

  The API provides a getRawID3v2() method to get an InputStream on ID3v2 frames.



- How to skip frames to have a seek feature ?

  See javazoom.jl.player.advanced.jlap source to learn how to skip frames.



- How much memory/CPU JLayer needs to run ?

  Here are our benchmark notes :

    - Heap use range : 1380KB to 1900KB - 370 classes loaded. 

    - Footprint : ~8MB under WinNT4/Win2K + J2SE 1.3 (Hotspot).

                  ~10MB under WinNT4/Win2K + J2SE 1.4.1 (Hotspot).

    - CPU usage : ~12% under PIII 800Mhz/WinNT4+J2SE 1.3 (Hotspot).

                  ~8% under PIII 1Ghz/Win2K+J2SE 1.3.1 (Hotspot).

                  ~12% under PIII 1Ghz/Win2K+J2SE 1.4.1 (Hotspot).

                  ~1% under PIII 1Ghz/Win2K+J2SE 1.5.0 (Hotspot).



- How to contact JLayer developers ?

  Try to post a thread on Java&MP3 online forums at :

  http://www.javazoom.net/services/forums/index.jsp

  You can also contact us at jlayer@javazoom.net for contributions.

 



KNOWN PROBLEMS :

--------------

99% of MP3 plays well with JLayer but some (1%) return an ArrayIndexOutOfBoundsException 

while playing. It might come from invalid audio frames. 

Workaround : Just try/catch ArrayIndexOutOfBoundsException in your code to skip 

             non-detected invalid frames.