JarCastingJImpulse
Java port of impulse, a small library for analysing sound output captured from Pulse Audio on Linux.
Dependencies
You will need a couple of libraries, but both should be available on your Linux system.
- libpulse0
- libfftw-3
If you are building this project from source, you will also need the -dev packages for these too.
Configuring your project
The Java Bit
The library is available in Maven Central.
Maven
<dependency>
<groupId>uk.co.bithatch</groupId>
<artifactId>jimpulse</artifactId>
<version>1.0</version>
</dependency>
Development versions (when available), will be the next version number, suffixed with -SNAPSHOT).
<dependency>
<groupId>uk.co.bithatch</groupId>
<artifactId>jimpulse</artifactId>
<version>1.1-SNAPSHOT</version>
</dependency>
The Native Bit
The native part of JImpulse is written using C and JNI, which itself uses the https://launchpad.net/impulse.bzr library by Ian Halpern.
The jars distributed by Bithatch only currently contain x86_64 binaries. These are automatically extracted when needed.
For other platforms you will need build yourself. The native components are built using [http://maven-nar.github.io/index.html](Maven NAR plugin). If you want to add support for other platforms, you'll need to edit the POM and build on appropriate hardware. NOTE: I do not use NAR Native ARchives, due to some problems with modularity.
Try It
You can run the test application from the command line (requires Maven).
mvn compile exec:java
If all is well, it will simple dump out a never ending stream of floating point numbers.
Usage
Integration with your own project is very simple.
The Monitor test application does the following :-
Impulse lib = new Impulse();
lib.initImpulse();
// You can set a different pulse device by it's index
// lib.setSourceIndex(0);
// Set to true to turn on fast fourier transform
boolean fft = false;
while(true) {
/* This is 256 bytes */
double[] data = lib.getSnapshot(fft);
for(double d : data) {
System.out.print(d + " ");
}
System.out.println();
}
