samer@0: /*
samer@0:  *	StreamSource.java
samer@0:  *
samer@0:  *	Copyright (c) 2012, Samer Abdallah, King's College London.
samer@0:  *	All rights reserved.
samer@0:  *
samer@0:  *	This software is provided AS iS and WITHOUT ANY WARRANTY;
samer@0:  *	without even the implied warranty of MERCHANTABILITY or
samer@0:  *	FITNESS FOR A PARTICULAR PURPOSE.
samer@0:  */
samer@0: 
samer@46: package ishara.audio;
samer@0: import  javax.sound.sampled.*;
samer@0: import  java.io.*;
samer@0: 
samer@0: public class StreamSource extends AudioSource
samer@0: {
samer@0: 	InputStream		in;
samer@0: 
samer@0: 	public StreamSource(AudioInputStream ain) throws Exception { super(ain.getFormat()); in=ain; }
samer@0: 	public StreamSource(AudioInputStream ain, AudioFormat target) throws Exception {
samer@0: 		this(prepareStream(ain,target));
samer@0: 	}
samer@0: 
samer@0: 	// AudioSource interface methods
samer@0: 	public void dispose() {
samer@0: 		print("Closing audio stream...");
samer@0: 		try { in.close(); } catch (IOException ex) {}
samer@0: 	}
samer@0: 
samer@0: 	public void start() {}
samer@0: 	public void stop() {}
samer@0: 	public int  read(byte [] buf, int off, int len) throws Exception {
samer@0: 		return in.read(buf,off,len);
samer@0: 	}
samer@0: 
samer@0: 	public static AudioInputStream prepareStream(AudioInputStream ain, AudioFormat target) throws Exception {
samer@0: 		// convert to target format if required
samer@0: 		print("Preparing audio stream...");
samer@0: 		print("  / audio format: "+ain.getFormat().toString());
samer@0: 		if (target==null) {
samer@0: 			AudioFormat fin=ain.getFormat();
samer@0: 			ain=convertFormat(new AudioFormat( fin.getSampleRate(), 16, fin.getChannels(), true, false), ain);
samer@0: 		} else {
samer@0: 			ain=convertFormat(target, ain);
samer@0: 		}
samer@0: 		print("  \\ final format: "+ain.getFormat().toString());
samer@0: 		return ain;
samer@0: 	}
samer@0: 
samer@0: 	private static AudioInputStream convertVia(AudioFormat fout, AudioInputStream sin, AudioFormat fint) throws Exception
samer@0: 	{
samer@0: 		print("  | Trying recursive via "+fint.toString());
samer@0: 		AudioInputStream sint=AudioSystem.getAudioInputStream(fint,sin);
samer@0: 		AudioFormat fres=sint.getFormat();
samer@0: 		if (!fres.equals(fint)) {
samer@0: 			print("  |            obtained  "+fres.toString());
samer@0: 		}
samer@0: 		return convertFormat(fout, sint);
samer@0: 	}
samer@0: 
samer@0: 	public static AudioInputStream convertFormat(AudioFormat fout, AudioInputStream sin) throws Exception
samer@0: 	{
samer@0: 		AudioFormat fin=sin.getFormat();
samer@0: 
samer@0: 		if (fin.equals(fout)) return sin;
samer@0: 		if (fin.getEncoding()!=AudioFormat.Encoding.PCM_SIGNED) {
samer@0: 			if (fin.getEncoding().getClass().getName().startsWith("javazoom.spi.")) {
samer@0: 				// these are broken, must go via 16 bit decode with no channels change
samer@0: 				print("  ! Detected noncompliant Javazoom decoder, going via 16 bit.");
samer@0: 				return convertVia( fout, sin, new AudioFormat( 
samer@0: 					fin.getSampleRate(), 16, fin.getChannels(), true, fout.isBigEndian()));
samer@0: 			}
samer@0: 
samer@0: 			// first get into PCM encoding, then try recursive
samer@0: 			try {
samer@0: 				return convertVia( fout, sin, new AudioFormat( 
samer@0: 					fin.getSampleRate(), fout.getSampleSizeInBits(),
samer@0: 					fin.getChannels(), true, fout.isBigEndian()));
samer@0: 			} catch (IllegalArgumentException ex) { 
samer@0: 				print("  * Direct conversion failed"); 
samer@0: 			}
samer@0: 			return convertVia( fout, sin, new AudioFormat( 
samer@0: 				fin.getSampleRate(), fin.getSampleSizeInBits(),
samer@0: 				fin.getChannels(), true, fout.isBigEndian()));
samer@0: 		} 
samer@0: 
samer@0: 		if (	!unify(fin.getChannels(),fout.getChannels()) 
samer@0: 			|| !unify(fin.getSampleSizeInBits(),fout.getSampleSizeInBits())) {
samer@0: 			// convert these before doing any sample rate conversion
samer@0: 			return convertVia(fout, sin, new AudioFormat( 
samer@0: 				fin.getSampleRate(), fout.getSampleSizeInBits(),
samer@0: 				fout.getChannels(), true, fout.isBigEndian()));
samer@0: 		}
samer@0: 
samer@0: 		// the only thing left is sample rate
samer@0: 		return AudioSystem.getAudioInputStream(fout,sin);
samer@0: 	}
samer@0: 
samer@0: 	private static boolean unify(int x, int y) { return x==-1 || y==-1 || x==y; }
samer@0: 	private static boolean unify(float x, float y) { return x==-1 || y==-1 || x==y; }
samer@0: }
samer@0: