/*
* _______ _____ _____ _____
* |__ __| | __ \ / ____| __ \
* | | __ _ _ __ ___ ___ ___| | | | (___ | |__) |
* | |/ _` | '__/ __|/ _ \/ __| | | |\___ \| ___/
* | | (_| | | \__ \ (_) \__ \ |__| |____) | |
* |_|\__,_|_| |___/\___/|___/_____/|_____/|_|
*
* -------------------------------------------------------------
*
* TarsosDSP is developed by Joren Six at IPEM, University Ghent
*
* -------------------------------------------------------------
*
* Info: http://0110.be/tag/TarsosDSP
* Github: https://github.com/JorenSix/TarsosDSP
* Releases: http://0110.be/releases/TarsosDSP/
*
* TarsosDSP includes modified source code by various authors,
* for credits and info, see README.
*
*/
package be.tarsos.dsp;
/**
* The oscilloscope generates a float array with
* array[i] an x coordinate in percentage
* array[i+1] the value of the amplitude in audio buffer
* array[i+2] another x coordinate in percentage
* array[i+3] the next amplitude in the audio buffer
*
* The implementation is based on the one by Dan Ellis found at http://www.ee.columbia.edu/~dpwe/resources/Processing/
* @author Dan Ellis
* @author Joren Six
*
*/
public class Oscilloscope implements AudioProcessor {
public static interface OscilloscopeEventHandler{
/**
* @param data The data contains a float array with:
* array[i] an x coordinate in percentage
* array[i+1] the value of the amplitude in audio buffer
* array[i+2] another x coordinate in percentage
* array[i+3] the next amplitude in the audio buffer
* @param event An audio Event.
*/
void handleEvent(float[] data, AudioEvent event);
}
float[] dataBuffer;
private final OscilloscopeEventHandler handler;
public Oscilloscope(OscilloscopeEventHandler handler){
this.handler = handler;
}
@Override
public boolean process(AudioEvent audioEvent) {
float[] audioBuffer = audioEvent.getFloatBuffer();
int offset = 0;
float maxdx = 0;
for (int i = 0; i < audioBuffer.length / 4; ++i) {
float dx = audioBuffer[i + 1] - audioBuffer[i];
if (dx > maxdx) {
offset = i;
maxdx = dx;
}
}
float tbase = audioBuffer.length / 2;
int length = Math.min((int) tbase, audioBuffer.length-offset);
if(dataBuffer == null || dataBuffer.length != length * 4){
dataBuffer = new float[length * 4];
}
int j = 0;
for(int i = 0; i < length - 1; i++){
float x1 = i / tbase;
float x2 = i / tbase;
dataBuffer[j] = x1;
dataBuffer[j+1] = audioBuffer[i+offset];
dataBuffer[j+2] = x2;
dataBuffer[j+3] = audioBuffer[i+1+offset];
j = j + 4;
}
handler.handleEvent(dataBuffer, audioEvent);
return true;
}
@Override
public void processingFinished() {
}
}