mp3towav.java

j2me音乐播放

/**
 * 
 * Mp3ToWav DataSource
 * 
 * JavaLayerME and MMAPI
 *
 */

package javazoom.jlme.decoder;


import java.io.*;
import javax.microedition.media.*;
import javax.microedition.media.protocol.*;
import java.io.IOException;


/* Audio datasource for converting mp3 to wav
 */
 
public class Mp3ToWav extends DataSource implements SourceStream, Runnable {

	// DataSource fields
    String locator = null;
    boolean connected = false;
    String contentType = null;

    // Comments field
    private boolean comments;
    
    // Defaults
    private int sampleRate = 44100;
    private int sampleSize = 16;
    private int channels = 2;
    private int endian = 0; // 0 for any, 1 for "little", 2 for "big"
    private int signed = 1; // 0 for any, 1 for "signed", 2 for "unsigned"

	// Productor
	Thread prodThread;
	public boolean stop=true;
	private byte[] fifo;
	private Object lock;
	private int getAskFor=0;
	private boolean locked=false;
	private int f_g=0;
	private int f_p=0;
	private int f_size=0;
	//private int FIFO_SIZE = 5000000;
	private int FIFO_SIZE = 50000;
	
	// Decoder JavaLayer
    private Decoder decoder;     
	private Header header; 
  	private BitStream bitstream;	
	private int dataLength=0;
   	private int lengthFrame;
	private byte[] bArray;
	private String file;
	private Object lock2;
	private boolean locked2=false;
   
 
    // The WAVe header
    private byte [] hdr = new byte[44];
    private int hdrSize;
    private int hdrOfs;
    private static final String[] headerComments= {"Chunk RIFF","Chunk RIFF","Chunk RIFF","Chunk RIFF","Check Size (Length unbounded)","Check Size (Length unbounded)","Check Size (Length unbounded)","Check Size (Length unbounded)","FCC Type - WAVE","FCC Type - WAVE","FCC Type - WAVE","FCC Type - WAVE","Chunk Format - fmt","Chunk Format - fmt","Chunk Format - fmt","Chunk Format - fmt","Check Size","Check Size","Check Size","Check Size","1 means PCM","1 means PCM","Nb of Channels","Nb of Channels","Frequence byte/sec","Frequence byte/sec","Frequence byte/sec","Frequence byte/sec","Frequence byte/sec","Frequence byte/sec","Frequence byte/sec","Frequence byte/sec","Quantification - bytes","Quantification - bytes","Quantification - bits","Quantification - bits","Chunk Data","Chunk Data","Chunk Data","Chunk Data","Check Size","Check Size","Check Size","Check Size"};


    /****************************************************************
     * Runnable implementation
     ****************************************************************/

    /**
     * Main process loop driving the media flow.
     */
    public void run() {
		boolean endOfFile=false;
		int toCopy=0;
		int lap=0;


		// First transfer the header
		for (int i=0; i<hdr.length;i++) {
			push(hdr[i]);	
			if (comments) System.out.println("-- Mp3Decoder Comments -- WRITING -- WAV header = " + hdr[i] + " - " + headerComments[i]);
		}
		
	    if (comments) System.out.println("-- Mp3Decoder Comments -- DataSource connected and ready for streaming");

			
		while(!endOfFile && connected) {
			if (stop) {		
			if (comments) 
				System.out.println("-- Mp3Decoder Comments -------> Synchro : DataSource locked");
				locked2=true;
				synchronized( lock2 ){
	    			// here is where you'd check obj's state
			     	while (locked2) {		
					    try {
						lock2.wait();
					    }
					    catch( InterruptedException e ){
							if (comments) e.printStackTrace();
					    }
					}
				}
			if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : DataSource unlocked ");
			}
			
			lap++;
	      try
		      {
		      	
		      	SampleBuffer output = (SampleBuffer)decoder.decodeFrame();
		      	lengthFrame = output.size();
	     		if (lengthFrame <= 0) {
					if (comments) System.out.println("-- Mp3Decoder Comments -- Mp3ToWav DataSource -- End Of File");
	     			endOfFile=true;break;
     			}

		      	bArray=output.getBuffer();
		 		
				if (f_size+lengthFrame<FIFO_SIZE) {
					if (f_p+lengthFrame<FIFO_SIZE) {
						// copy en un bloc
					   	System.arraycopy(bArray, 0,
					     fifo, f_p,
					     lengthFrame);}
					else {
						// copy en deux blocs
						// 1er bloc : FIFO_SIZE-f_p bytes copied
					   	System.arraycopy(bArray, 0,
					     fifo, f_p,
					     FIFO_SIZE-f_p);
						// 2eme bloc : lengthFrame-(FIFO_SIZE-f_p) bytes copied from the byte FIFO_SIZE-f_p   
					   	System.arraycopy(bArray, FIFO_SIZE-f_p,
					     fifo, 0,
					     lengthFrame-FIFO_SIZE+f_p);
					}    
					f_p=(f_p+lengthFrame)%FIFO_SIZE;
					f_size=f_size+lengthFrame;
					if (f_size>getAskFor && locked==true) {
						getAskFor=0;
						locked=false;
					   	synchronized(lock){
    						if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : Notify buffer ready for reading");
							lock.notifyAll(); 
						}
					}
				}
				else {
					// buffer full
					if (comments) System.out.println ("-- Mp3Decoder Comments -- CANT WRITE ANYMORE DATA -- Buffer Full -----");
				}
			
				
		 		if (comments) System.out.println("-- Mp3Decoder Comments -- WRITING -- lap "+lap+" -- buffering "+ f_size*100/FIFO_SIZE + " % -- "  + f_size + "/" + FIFO_SIZE + " --"  );
		      	bitstream.closeFrame();
				header = bitstream.readFrame();
			} catch (Exception e) {
		 		System.out.println("Mp3ToWav::run:Exception in thread prodthread");
			}
		
			    	
		}
 		if (comments) System.out.println("-- Mp3Decoder Comments -- End of the thread used by Mp3ToWav for writing in the buffer");   	

	}
    
    /****************************************************************
     * DataSource implementation
     ****************************************************************/

    public Mp3ToWav(String l, boolean c) {
    	super(l);
		
		System.out.println("Enter Mp3ToWav Constructor>>" + l);
		
    	locator=l;
    	comments=c;
		// Captures audio and wraps it into WAV content type
		contentType = "audio/x-wav";
		fifo=new byte[FIFO_SIZE];
		lock=new Object();
		lock2=new Object();
    }

 
    public void setLocator(String ml) {
	locator = ml;
    }

    public String getLocator() {
	return locator;
    }

    public String getContentType() {
	if (!connected)
	    return null;
	return contentType;
    }

    public void setContentType(String type) {
	contentType = type;
    }

    public Control[] getControls() {
	return new Control[0];
    }

    public Control getControl(String controlType) {
	return null;
    }


    /**
     * Parse the protocol part of the locator string.
     */
    static public String getProtocol(String loc) {
	String proto = "";
	int idx = loc.indexOf(':');

	if( idx != -1) {
	    proto = loc.substring(0,idx);
	}

	return proto;
    }

   /* return the numeric value for a property */
    private int tryParam(String tok, String prop, int def) {
	if (tok.startsWith(prop)) {
	    tok = tok.substring(prop.length(), tok.length());
	    
	    if (prop.equals("signed=")) {
		if (tok.equals("signed"))
		    return 1; // SIGNED
		else if (tok.equals("unsigned"))
		    return 2; // UNSIGNED
	    } else if (prop.equals("endian=")) {
		if (tok.equals("little"))
		    return 1; // LITTLE_ENDIAN
		else if (tok.equals("big"))
		    return 2; // BIG_ENDIAN
	    } else {
		try {
		    return Integer.parseInt(tok);
		} catch (Exception e) {
		}
	    }
	}
	return def;
    }

    /* Parse the URL, extract and validate the properties */
    private boolean parseLocator() {
		String loc = getLocator();
	
		if (comments) System.out.println("-- Mp3Decoder Comments -- Parse Locator : " + loc);
	
		if (!loc.endsWith(".mp3"))
		    return false;
		
		return true;
    }

    public void connect() throws IOException {
		
		System.out.println("Enter connect");
		
		if (!parseLocator())
			throw new IOException("Invalid locator");

		// open the file and create the header
		// throw an exception if the file has not been opened

		// Open the file
		try {
		    if (comments) 
				System.out.println("-- Mp3Decoder Comments -- Create decoder and connect the dataSource (Push the wav header)");
			InputStream in = null;
			in = getClass().getResourceAsStream(getLocator());
			if(in == null)
			{
				System.out.println("无法获取music数据源!");
				return;
			}
			else
			{
			   	bitstream = new BitStream(in);	 
			   	
		    	header = bitstream.readFrame();
	    		decoder = new Decoder(header,bitstream);
	      		if (comments) 
					System.out.println("-- Mp3Decoder Comments -- WAV Stream mode : Frequency: "
							+decoder.getOutputFrequency() + ",Channels: " 
							+ decoder.getOutputChannels());
			}
    		System.gc();
		  }
		catch (Exception e) {
			if (comments) 
				System.out.println("Couldn't open audio input");
			System.out.println("异常原因为:" + e.getMessage() + "/" + e.getClass());
	   		throw new IOException("Couldn't open audio input");
		}   	

		
		// Generate the WAV header
		createHeader(sampleRate, sampleSize, channels);
		connected = true;
		System.out.println("Generate the WAV header:okay");
    
    	// Start the playback loop.
		prodThread = new Thread(this);
		prodThread.start();
    }

    public void disconnect() {
		//stop();
		if (comments) System.out.println("-- Mp3Decoder Comments -- Mp3ToWav DataSource -- Disconnected");   	


		locked2=false;
	   	synchronized(lock2){
			if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : Notify DataSource");
			lock2.notifyAll(); 
		}

		connected = false;
		
		fifo=null;
		System.gc();
    }

    public void start() throws IOException {
 		if (comments) System.out.println("-- Mp3Decoder Comments -- Mp3ToWav DataSource -- Started");   	
 		stopProd(false);
		locked2=false;
	   	synchronized(lock2){
			if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : Notify DataSource");
			lock2.notifyAll(); 
		}

    }

    public void stop() {
 		if (comments) System.out.println("-- Mp3Decoder Comments -- Mp3ToWav DataSource -- Stopped");   	
		locked=false;
	   	synchronized(lock){
			if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : Notify Buffer");
			lock.notifyAll(); 
		}

	 	stopProd(true);
    }

    public SourceStream[] getStreams() {
	return new SourceStream[] { this };
    }

    
    /****************************************************************
     * SourceStream implementation
     ****************************************************************/

    public ContentDescriptor getContentDescriptor() {
	return new ContentDescriptor(getContentType());
    }

    public long getContentLength() {
	return -1;
    }

    public int read(byte[] buffer, int offset, int length) throws IOException {
		if (comments) System.out.println("-- Mp3Decoder Comments -- ASK FOR READING -- offset =>"  + offset + ", length asked =>"  + length  );
 
    
    	int totalCopy=length;

		while (f_size<=totalCopy && connected) {
			// waiting
			getAskFor=totalCopy;
			locked=true;
			if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : Buffer Locked  (empty)");	
				wait_get();
			if (comments) System.out.println("-- Mp3Decoder Comments -------> Synchro : Buffer Unlocked  (ready for reading)");
		}
		//if (f_size<=totalCopy) return 0;
		
		
			if (comments) System.out.println("-- Mp3Decoder Comments -- READING -- " + totalCopy + " -- f_size : " + f_size);
			
			if (f_g+totalCopy<FIFO_SIZE) {
				// copy en un bloc
			   	System.arraycopy(fifo, f_g,
			     buffer, offset,
			     totalCopy);}
			else {
				// copy en deux blocs
				// 1er bloc : FIFO_SIZE-f_g bytes copi閟
			   	System.arraycopy(fifo, f_g,
			     buffer, offset,
			    FIFO_SIZE-f_g);
				// 2eme bloc : totalCopy-(FIFO_SIZE-f_g) bytes copi閟