/*
*
      
_______
                       
_____
   
_____ _____
  

*
     
|__
   
__|
                     
|
  
__ \ / ____|__ \
 

*
        
| | __ _ _ __ ___
  
______| || | (___ | |__) |
*
        
| |/ _` | '__/ __|/ _ \/ __| |
  
| |\___ \|___/
 

*
        
| | (_| | |
  
\__ \ (_) \__ \ |__| |____) | |
     

*
        
|_|\__,_|_|
  
|___/\___/|___/_____/|_____/|_|
     

*
                                                         

* -------------------------------------------------------------
*
* 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() {
	
}

}