samer@1: /*
samer@1:  *	StreamSource.java
samer@1:  *
samer@1:  *	Copyright (c) 2000, Samer Abdallah, King's College London.
samer@1:  *	All rights reserved.
samer@1:  *
samer@1:  *	This software is provided AS iS and WITHOUT ANY WARRANTY;
samer@1:  *	without even the implied warranty of MERCHANTABILITY or
samer@1:  *	FITNESS FOR A PARTICULAR PURPOSE.
samer@1:  */
samer@1: 
samer@1: package samer.audio;
samer@1: 
samer@1: import  samer.core.*;
samer@1: import  samer.core.types.*;
samer@1: import  samer.core.util.*;
samer@1: import  samer.tools.*;
samer@1: import  javax.sound.sampled.*;
samer@1: import  javax.swing.*;
samer@1: import  java.io.*;
samer@1: import  java.net.URL;
samer@1: import  java.util.*;
samer@1: 
samer@1: /**
samer@1: 	An AudioSource that read from an input stream. Can read any
samer@1: 	format for which the appropriate JavaSound plug-in is installed on
samer@1: 	your system, eg WAV, AU, MP3, OGG. The implementation of 
samer@1: 	AudioSource.reader() returns a Task which gets samples from the audio 
samer@1: 	files, going through the play list one by one. If the loop flag
samer@1: 	is true, then samples are returned indefinitely by looping through the
samer@1: 	playlist; otherwise, an EOFException is thrown if an attempt is made
samer@1: 	to read beyond the end of the last file.
samer@1: 	
samer@1: 	Properties read from current environment:
samer@1: 	<dl>
samer@1: 		<dt>current<dd>Current file (String)
samer@1: 		<dt>loop<dd>Loop playlist? (Boolean) [true]
samer@1: 	</dl>
samer@1: 					
samer@1: */
samer@1: 
samer@1: public class StreamSource implements AudioSource
samer@1: {
samer@1: 	int				channelsToMix;
samer@1: 	AudioInputStream source;
samer@1: 	InputStream		in=null;
samer@1: 	AudioFormat		format=null;
samer@1: 	byte[]  			byte_buf=null;
samer@1: 	int				chunk=0;
samer@1: 
samer@1: 	/**
samer@1: 	 * Construct a StreamSource initialised with current file and loop initialised
samer@1: 	 * from the current Environment. No exception is thrown if the current file
samer@1: 	 */
samer@1: 	public StreamSource(AudioInputStream s) throws Exception { source=s; }
samer@1: 	public StreamSource(InputStream s) throws Exception { source=AudioSystem.getAudioInputStream(s); }
samer@1: 	public StreamSource(File file) throws Exception { source=AudioSystem.getAudioInputStream(file); }
samer@1: 	public StreamSource(URL url) throws Exception { source=AudioSystem.getAudioInputStream(url); }
samer@1: 
samer@1: 	public void dispose() { close(); }
samer@1: 
samer@1: 	/** Returns current file */
samer@1: 	public void setTargetFormat(AudioFormat f) { format=f; }
samer@1: 
samer@1: 	public AudioFormat getFormat() { return format; }
samer@1: 
samer@1: 	public boolean isOpen() { return in!=null; }
samer@1: 
samer@1: 	/** Closes current input stream */
samer@1: 	public synchronized void close() {
samer@1: 		try { 
samer@1: 			if (in!=null) {
samer@1: 				Shell.trace("Closing audio stream...");
samer@1: 				in.close(); in=null; byte_buf=null; 
samer@1: 			}
samer@1: 		}
samer@1: 		catch (IOException ex) {}
samer@1: 	}
samer@1: 
samer@1: 	/** Opens the playlist starting with the first file.  */
samer@1: 	public synchronized void open() throws Exception { if (!isOpen()) openCurrent(); }
samer@1: 
samer@1: 	/** Opens the current file. Next read will returns samples
samer@1: 	 *  from head of given file. If setFormat() was called previously, then
samer@1: 	 *  we will attempt to do format conversion. */
samer@1: 	private synchronized void openCurrent() throws Exception
samer@1: 	{
samer@1: 		AudioInputStream     s=source;
samer@1: 		AudioFormat				fmt1, af=s.getFormat();
samer@1: 
samer@1: 		Shell.trace("  format: "+af);
samer@1: 
samer@1: 		// convert to target format if required
samer@1: 		if (format!=null) {
samer@1: 			if (!format.equals(af)) {
samer@1: 				Shell.trace("  converting to "+format);
samer@1: 				if (af.getChannels()>format.getChannels()) {
samer@1: 					Shell.trace("  channels mix down required.");
samer@1: 					fmt1 = new AudioFormat( format.getEncoding(), format.getSampleRate(), 
samer@1: 								format.getSampleSizeInBits(), 
samer@1: 								af.getChannels(), format.getFrameSize(), format.getFrameRate(), format.isBigEndian());
samer@1: 
samer@1: 					channelsToMix = af.getChannels();
samer@1: 				} else {
samer@1: 					channelsToMix = 0;
samer@1: 					fmt1=format;
samer@1: 				}
samer@1: 				s=convertFormat(s,af,fmt1);
samer@1: 			}
samer@1: 		}
samer@1: 
samer@1: 		// If we have a reader task, then update the byte buffer
samer@1: 		if (chunk>0) setByteBuffer();
samer@1: 
samer@1: 		// Shell.trace("stream format: "+s.getFormat());
samer@1: 		in = new BufferedInputStream(s,64*1024);
samer@1: 	}
samer@1: 
samer@1: 	/** Returns number of bytes available in current file */
samer@1: 	public int available() throws Exception { return in.available(); }
samer@1: 
samer@3: 	public float getRate()     { return source.getFormat().getFrameRate(); }
samer@3: 	public int   getChannels() { return source.getFormat().getChannels(); }
samer@3: 
samer@1: 	private void setChunkSize(int s) { chunk=s; }
samer@1: 	private void setByteBuffer() {
samer@1: 		byte_buf = new byte[2*chunk*(channelsToMix>0 ? channelsToMix : 1)];
samer@1: 	}
samer@1: 
samer@1: 	/** Returns a Task which copies samples as doubles into the given
samer@1: 	 *  buffer between the given positions. */
samer@1: 	public Task reader(final double [] dbuf, final int off, final int len) {
samer@1: 		setChunkSize(len);
samer@1: 		if (in!=null) setByteBuffer();
samer@1: 
samer@1: 		return new AnonymousTask() {
samer@1: 			public void run() throws Exception {
samer@1: 				int n = 0;
samer@1: 
samer@1: 				synchronized (StreamSource.this) {
samer@1: 					int blen = byte_buf.length;
samer@1: 					while (n < blen) {
samer@1: 						int count = in.read(byte_buf, n, blen - n);
samer@1: 						if (count > 0) n+=count;
samer@1: 						else throw new EOFException();
samer@1: 					}
samer@1: 				}
samer@1: 				if (channelsToMix>0) Util.shortToDoubleMixDown(byte_buf,dbuf,off,len,channelsToMix);
samer@1: 				else Util.shortToDouble(byte_buf,dbuf,off,len);
samer@1: 			}
samer@1: 		};
samer@1: 	}
samer@1: 
samer@1: 	/** Returns a Task which copies samples as floats into the given
samer@1: 	 *  buffer between the given positions. */
samer@1: 	public Task reader(final float [] dbuf, final int off, final int len) {
samer@1: 		setChunkSize(len);
samer@1: 		if (in!=null) setByteBuffer();
samer@1: 
samer@1: 		return new AnonymousTask() {
samer@1: 			public synchronized void run() throws Exception {
samer@1: 				int n = 0;
samer@1: 
samer@1: 				synchronized (StreamSource.this) {
samer@1: 					int blen = byte_buf.length;
samer@1: 					while (n < blen) {
samer@1: 						int count = in.read(byte_buf, n, blen - n);
samer@1: 						if (count > 0) n+=count;
samer@1: 						else throw new EOFException();
samer@1: 					}
samer@1: 				}
samer@1: 				if (channelsToMix>0) Util.shortToFloatMixDown(byte_buf,dbuf,off,len,channelsToMix);
samer@1: 				else Util.shortToFloat(byte_buf,dbuf,off,len);
samer@1: 			}
samer@1: 		};
samer@1: 	}
samer@1: 
samer@1: 	private static AudioInputStream convertFormat(AudioInputStream sin, AudioFormat fin, AudioFormat fout) throws Exception
samer@1: 	{
samer@1: 		if (fin.equals(fout)) return sin;
samer@1: 		else if (fin.getEncoding()==AudioFormat.Encoding.PCM_SIGNED) {
samer@1: 			try { return AudioSystem.getAudioInputStream(fout,sin); }
samer@1: 			catch (IllegalArgumentException ex) { Shell.trace("Direct conversion failed"); }
samer@1: 
samer@1: 			AudioFormat fint = new AudioFormat(  // PCM
samer@1: 				fout.getSampleRate(), fout.getSampleSizeInBits(),
samer@1: 				fin.getChannels(), true, fout.isBigEndian());
samer@1: 			Shell.trace("Trying PCM conversion via "+fint.toString());
samer@1: 			return AudioSystem.getAudioInputStream(fout,AudioSystem.getAudioInputStream(fint,sin));
samer@1: 		} else {
samer@1: 		// First, check for MP3 - if so, cannot convert number of channels
samer@1: 			if (fin.getChannels()==fout.getChannels() && fin.getSampleRate()==fout.getSampleRate()) {
samer@1: 				Shell.trace("Trying direct decoding from "+fin.getEncoding().toString());
samer@1: 				return AudioSystem.getAudioInputStream(fout,sin);
samer@1: 			} else {
samer@1: 				AudioFormat fint = new AudioFormat( 
samer@1: 					fin.getSampleRate(), fout.getSampleSizeInBits(),
samer@1: 					fin.getChannels(), true, fout.isBigEndian());
samer@1: 				Shell.trace("Trying conversion via "+fint.toString());
samer@1: 				return convertFormat(AudioSystem.getAudioInputStream(fint,sin),fint,fout);
samer@1: 			}
samer@1: 		}
samer@1: 	}
samer@1: }
samer@1: