samer@1: /*
samer@1:  *	FileSource.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.util.*;
samer@1: import  java.nio.ByteBuffer;
samer@1: 
samer@1: /**
samer@1: */
samer@1: 
samer@1: 
samer@1: public abstract class MultiFileAudioStream extends InputStream 
samer@1: {
samer@1: 	List<File>				list=null;
samer@1: 	ListIterator<File>	it=null;
samer@1: 	int						channelsToMix;
samer@1: 	File						curFile=null;
samer@1: 	InputStream				in=null;
samer@1: 	AudioFormat				format=null, inFormat=null;
samer@1: 	boolean              loop=false;
samer@1: 
samer@1: 	/**
samer@1: 	 * Construct a FileSource initialised with current file and loop initialised
samer@1: 	 * from the current Environment. No exception is thrown if the current file
samer@1: 	 * cannot be opened, however, you must be sure to set it to a valid file
samer@1: 	 * (or to set a playlist) before trying to read any samples.
samer@1: 	 */
samer@1: 	public MultiFileAudioStream(AudioFormat target, List<File> files)
samer@1: 	{
samer@1: 		list=files;
samer@1: 		format=target;
samer@1: 	}
samer@1: 
samer@1: 	public AudioFormat getFormat() { return format; }
samer@1: 
samer@1: 	/** Set playlist to all WAV files in given directory */
samer@1: 	public List<File> directory(File dir, String ext) {
samer@1: 		return Arrays.asList(dir.listFiles(getFileFilter(ext))); 
samer@1: 	}
samer@1: 
samer@1: 	private static java.io.FileFilter getFileFilter(final String ext) { 
samer@1: 		return new java.io.FileFilter() {
samer@1: 			public boolean accept(File file) {
samer@1: 				return file.getName().toLowerCase().endsWith(ext);
samer@1: 			}
samer@1: 		};
samer@1: 	}
samer@1: 
samer@1: 	public synchronized List<File> getPlaylist() { return list; }
samer@1: 
samer@1: 	/** Go back to start of playlist. Next block of samples will be from head
samer@1: 	 *  of first file in playlist. Will throw an exception if there is no playlist */
samer@1: 	public synchronized void rewind() throws IOException {
samer@1: 		it=list.listIterator(); next();
samer@1: 	}
samer@1: 
samer@1: 	/** Move to head of next file in playlist */
samer@1: 	public synchronized void next() throws IOException
samer@1: 	{
samer@1: 		boolean wasOpen=isOpen();
samer@1: 
samer@1: 		if (wasOpen) close();
samer@1: 		if (!it.hasNext()) {
samer@1: 			if (!loop) throw new EOFException();
samer@1: 			it=list.listIterator();
samer@1: 			if (!it.hasNext()) throw new IOException("no files in playlist");
samer@1: 		}
samer@1: 		curFile=it.next();
samer@1: 		if (wasOpen) openCurrent();
samer@1: 	}
samer@1: 
samer@1: 	/** Move to head of previous file in playlist */
samer@1: 	public synchronized void prev() throws Exception
samer@1: 	{
samer@1: 		boolean wasOpen=isOpen();
samer@1: 		if (wasOpen) close();
samer@1: 		if (!it.hasPrevious()) {
samer@1: 			if (!loop) throw new EOFException();
samer@1: 			it=list.listIterator(list.size());
samer@1: 			if (!it.hasPrevious()) throw new Exception("no files in playlist");
samer@1: 		}
samer@1: 		curFile=it.previous();
samer@1: 		if (wasOpen) openCurrent();
samer@1: 	}
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; 
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 { rewind(); 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 IOException
samer@1: 	{
samer@1: 		try {
samer@1: 			File file=curFile;
samer@1: 			Shell.trace("\nFileSource:Opening audio file "+file);
samer@1: 
samer@1: 			AudioInputStream		s=AudioSystem.getAudioInputStream(file);
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: 						int frameSize = af.getChannels()*format.getSampleSizeInBits()/8;
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(), frameSize, 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: 					Shell.trace("  converting via "+fmt1);
samer@1: 					s=convertFormat(s,af,fmt1);
samer@1: 					inFormat = fmt1;
samer@1: 				} else {
samer@1: 					Shell.trace("  no formation conversion required");
samer@1: 					channelsToMix = 0;
samer@1: 					inFormat = af;
samer@1: 				}
samer@1: 			} else {
samer@1: 				Shell.trace("  using stream native format");
samer@1: 				channelsToMix = 0;
samer@1: 				inFormat = af;
samer@1: 			}
samer@1: 			in=s;
samer@1: 		}
samer@1: 		catch (Exception ex) { throw new IOException("Failed to open audio file"); }
samer@1: 	}
samer@1: 
samer@1: 	/** Returns number of bytes available in current file */
samer@1: 	public int available() { 
samer@1: 		try {
samer@1: 			return in.available(); 
samer@1: 		}
samer@1: 		catch (Exception ex) { return 0; }
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 int read(byte [] buf, int off, int len) throws IOException {
samer@1: 
samer@1: 		// loop until len samples copied into dbuf
samer@1: 		int rem=len, pos=off;
samer@1: 		while (rem>0) {
samer@1: 			int chunk = in.read(buf, pos, rem);
samer@1: 			if (chunk > 0) { // append this chunk to output
samer@1: 				pos+=chunk; rem-=chunk;
samer@1: 			} else if (it!=null) next(); // next file if there is one
samer@1: 			else if (!loop) throw new EOFException(); // not looping and no more files
samer@1: 			else rewind(); // back to first file
samer@1: 		}
samer@1: 		return len;
samer@1: 	}
samer@1: 
samer@1: 
samer@1: 	private static AudioInputStream convertFormat(AudioInputStream sin, AudioFormat fin, AudioFormat fout) throws Exception
samer@1: 	{
samer@1: 		Shell.trace("\nconvertFormat:");
samer@1: 		Shell.trace("  | source: "+fin.toString());
samer@1: 		Shell.trace("  | target: "+fout.toString());
samer@1: 
samer@1: 		if (fin.equals(fout)) return sin;
samer@1: 		else if (fin.getEncoding()==AudioFormat.Encoding.PCM_SIGNED) {
samer@1: 			try { 
samer@1: 				Shell.trace("  | Trying direct (PCM) from "+fin.getEncoding().toString());
samer@1: 				return AudioSystem.getAudioInputStream(fout,sin); 
samer@1: 			}
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 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 recursive via "+fint.toString());
samer@1: 				return convertFormat(AudioSystem.getAudioInputStream(fint,sin),fint,fout);
samer@1: 			}
samer@1: 		}
samer@1: 	}
samer@1: }
samer@1: