Java to transcode and manipulate mp3 files

Question

I am looking for a java library to efficently/fast transcodig and manipulation mp3 files. I am working on a sophisticated streaming server that mixes music and has some other functions to allow to users to interact with each other. A recommendation functonallity for example should fade over the stream of the sending user to the reciever of the recommendation.

All the fuctionallity is implemented right now and works well using UPnP-AV devices. The next step would be not to simply switch the tracks like I do it now. It should be a smooth fade between songs.

Any suggestions on that? Mayby java is not the right solution to work with sound. If you know a better way to do transcoding and manipuation of audio let me know.

(Transcoding is needed because not all audio sources are available as mp3 but internally I do work only with MP3)

Answer 1

One of the best MP3 encoders out there is LAME. There is an API wrapper for Java called LAMEOnJ, but it requires a JNIEasy license, the free version of which has to be redownloaded every 5 days. Frankly, I don't know why you'd want to work with MP3 internally as opposed to WAV files; it's probably going to be more work. Plus, there's the patent thing.

All around, you're probably better off working with the Java Sound API. There's a good open source package out there called Tritonus. Tritonus only supports the full API (specifically, sound output) on Linux, but they have some useful plugins that work on any platform (including an MP3 encoder, the quality of which I can't speak to).

Answer 2

Or use Xuggler to decode or encode MP3 files. It uses LAME under the covers, is open-source (LGPL) and free, and runs on Mac, Windows and Linux.