您如何播放长音频剪辑？

Question

我编写了一个简单的类，可以在一个简单的游戏中播放音频文件。它适用于诸如枪声或爆炸声之类的小声音，但是当我尝试将其用于背景音乐时，出现以下错误：“未能分配剪辑数据：请求的缓冲区太大。”
我假设这意味着文件太大，但是如何解决呢？资源：

import java.io.File;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.Clip;

public class Sound{

private Clip clip;

public Sound(String filepath){
    System.out.println(filepath);
    File file = new File(filepath);
    try {
        clip = AudioSystem.getClip();
        AudioInputStream inputStream = AudioSystem.getAudioInputStream(file);
        clip.open(inputStream);
    } catch (Exception e) {
        System.err.println(e.getMessage());
    }
}

public void play(){
    System.out.println("play");
    if(clip.isActive()){
        clip.stop();
    }
    clip.setFramePosition(0);
    clip.start();
}

public void stop(){
    clip.stop();
}

public void loop(){
    if(!clip.isActive()){
        clip.setFramePosition(0);
        clip.loop(Clip.LOOP_CONTINUOUSLY);
    }else{
        System.out.println("ALREADY PLAYING");
    }

}

public boolean getActive(){return clip.isActive();}
}

Answer 1

使用BigClip。这是我玩12-18分钟（或更多1分钟）的MP3的课堂。

它要求mp3plugin.jar在运行时类路径上实际加载MP3格式的声音，但这不是重点。重点是：

1. BigClip会将声音文件加载到JVM之前允许的最大内存中OutOfMemoryError。

import java.awt.Component;
import javax.swing.*;
import javax.sound.sampled.*;
import java.io.*;
import java.util.logging.*;
import java.util.Arrays;

import java.net.URL;
import javax.swing.JOptionPane;

class BigClipExample {

    public static void main(String[] args) throws Exception {
        URL url = new URL("http://pscode.org/media/leftright.wav");
        BigClip clip = new BigClip();
        AudioInputStream ais = AudioSystem.getAudioInputStream(url);
        clip.open(ais);
        clip.start();
        JOptionPane.showMessageDialog(null, "BigClip.start()");
        clip.loop(4);
        JOptionPane.showMessageDialog(null, "BigClip.loop(4)");
        clip.setFastForward(true);
        clip.loop(8);
        // the looping/FF combo. reveals a bug..
        // there is a slight 'click' in the sound that should not be audible
        JOptionPane.showMessageDialog(null, "Are you on speed?");
    }
}

/** An implementation of the javax.sound.sampled.Clip that is designed
to handle Clips of arbitrary size, limited only by the amount of memory
available to the app.    It uses the post 1.4 thread behaviour (daemon thread)
that will stop the sound running after the main has exited.
<ul>
<li>2012-02-29 - Reworked play/loop to fix several bugs.
<li>2009-09-01 - Fixed bug that had clip ..clipped at the end, by calling drain() (before
calling stop()) on the dataline after the play loop was complete. Improvement to frame
and microsecond position determination.
<li>2009-08-17 - added convenience constructor that accepts a Clip. Changed the private
convertFrameToM..seconds methods from 'micro' to 'milli' to reflect that they were dealing
with units of 1000/th of a second.
<li>2009-08-14 - got rid of flush() after the sound loop, as it was cutting off tracks just
before the end, and was found to be not needed for the fast-forward/rewind functionality it
was introduced to support.
<li>2009-08-11 - First binary release.
</ul>
N.B. Remove @Override notation and logging to use in 1.3+
@since 1.5
@version 2012-02-29
@author Andrew Thompson 
@author Alejandro Garcia */
class BigClip implements Clip, LineListener {

    /** The DataLine used by this Clip. */
    private SourceDataLine dataLine;

    /** The raw bytes of the audio data. */
    private byte[] audioData;

    /** The stream wrapper for the audioData. */
    private ByteArrayInputStream inputStream;

    /** Loop count set by the calling code. */
    private int loopCount = 1;
    /** Internal count of how many loops to go. */
    private int countDown = 1;
    /** The start of a loop point.    Defaults to 0. */
    private int loopPointStart;
    /** The end of a loop point.    Defaults to the end of the Clip. */
    private int loopPointEnd;

    /** Stores the current frame position of the clip. */
    private int framePosition;

    /** Thread used to run() sound. */
    private Thread thread;
    /** Whether the sound is currently playing or active. */
    private boolean active;
    /** Stores the last time bytes were dumped to the audio stream. */
    private long timelastPositionSet;

    private int bufferUpdateFactor = 2;

    /** The parent Component for the loading progress dialog.    */
    Component parent = null;

    /** Used for reporting messages. */
    private Logger logger = Logger.getAnonymousLogger();

    /** Default constructor for a BigClip.    Does nothing.    Information from the
    AudioInputStream passed in open() will be used to get an appropriate SourceDataLine. */
    public BigClip() {}

    /** There are a number of AudioSystem methods that will return a configured Clip.    This
    convenience constructor allows us to obtain a SourceDataLine for the BigClip that uses
    the same AudioFormat as the original Clip.
    @param clip Clip The Clip used to configure the BigClip. */
    public BigClip(Clip clip) throws LineUnavailableException {
        dataLine = AudioSystem.getSourceDataLine( clip.getFormat() );
    }

    /** Provides the entire audio buffer of this clip.
    @return audioData byte[] The bytes of the audio data that is loaded in this Clip. */
    public byte[] getAudioData() {
        return audioData;
    }

    /** Sets a parent component to act as owner of a "Loading track.." progress dialog.
    If null, there will be no progress shown. */
    public void setParentComponent(Component parent) {
        this.parent = parent;
    }

    /** Converts a frame count to a duration in milliseconds. */
    private long convertFramesToMilliseconds(int frames) {
        return (frames/(long)dataLine.getFormat().getSampleRate())*1000;
    }

    /** Converts a duration in milliseconds to a frame count. */
    private int convertMillisecondsToFrames(long milliseconds) {
        return (int)(milliseconds/dataLine.getFormat().getSampleRate());
    }

    @Override
    public void update(LineEvent le) {
        logger.log(Level.FINEST, "update: " + le );
    }

    @Override
    public void loop(int count) {
        logger.log(Level.FINEST, "loop(" + count + ") - framePosition: " + framePosition);
        loopCount = count;
        countDown = count;
        active = true;
        inputStream.reset();

        start();
    }

    @Override
    public void setLoopPoints(int start, int end) {
        if (
            start<0 ||
            start>audioData.length-1 ||
            end<0 ||
            end>audioData.length
            ) {
            throw new IllegalArgumentException(
                "Loop points '" +
                start +
                "' and '" +
                end +
                "' cannot be set for buffer of size " +
                audioData.length);
        }
        if (start>end) {
            throw new IllegalArgumentException(
                "End position " +
                end +
                " preceeds start position " + start);
        }

        loopPointStart = start;
        framePosition = loopPointStart;
        loopPointEnd = end;
    }

    @Override
    public void setMicrosecondPosition(long milliseconds) {
        framePosition = convertMillisecondsToFrames(milliseconds);
    }

    @Override
    public long getMicrosecondPosition() {
        return convertFramesToMilliseconds(getFramePosition());
    }

    @Override
    public long getMicrosecondLength() {
        return convertFramesToMilliseconds(getFrameLength());
    }

    @Override
    public void setFramePosition(int frames) {
        framePosition = frames;
        int offset = framePosition*format.getFrameSize();
        try {
            inputStream.reset();
            inputStream.read(new byte[offset]);
        } catch(Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public int getFramePosition() {
        long timeSinceLastPositionSet = System.currentTimeMillis() - timelastPositionSet;
        int size = dataLine.getBufferSize()*(format.getChannels()/2)/bufferUpdateFactor;
        int framesSinceLast = (int)((timeSinceLastPositionSet/1000f)*
            dataLine.getFormat().getFrameRate());
        int framesRemainingTillTime = size - framesSinceLast;
        return framePosition
            - framesRemainingTillTime;
    }

    @Override
    public int getFrameLength() {
        return audioData.length/format.getFrameSize();
    }

    AudioFormat format;

    @Override
    public void open(AudioInputStream stream) throws
        IOException,
        LineUnavailableException {

        AudioInputStream is1;
        format = stream.getFormat();

        if (format.getEncoding()!=AudioFormat.Encoding.PCM_SIGNED) {
            is1 = AudioSystem.getAudioInputStream(
                AudioFormat.Encoding.PCM_SIGNED, stream );
        } else {
            is1 = stream;
        }
        format = is1.getFormat();
        InputStream is2;
        if (parent!=null) {
            ProgressMonitorInputStream pmis = new ProgressMonitorInputStream(
                parent,
                "Loading track..",
                is1);
            pmis.getProgressMonitor().setMillisToPopup(0);
            is2 = pmis;
        } else {
            is2 = is1;
        }

        byte[] buf = new byte[ 2^16 ];
        int totalRead = 0;
        int numRead = 0;
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        numRead = is2.read( buf );
        while (numRead>-1) {
            baos.write( buf, 0, numRead );
            numRead = is2.read( buf, 0, buf.length );
            totalRead += numRead;
        }
        is2.close();
        audioData = baos.toByteArray();
        AudioFormat afTemp;
        if (format.getChannels()<2) {
            afTemp = new AudioFormat(
                format.getEncoding(),
                format.getSampleRate(),
                format.getSampleSizeInBits(),
                2,
                format.getSampleSizeInBits()*2/8, // calculate frame size
                format.getFrameRate(),
                format.isBigEndian()
                );
        } else {
            afTemp = format;
        }

        setLoopPoints(0,audioData.length);
        dataLine = AudioSystem.getSourceDataLine(afTemp);
        dataLine.open();
        inputStream = new ByteArrayInputStream( audioData );
    }

    @Override
    public void open(AudioFormat format,
        byte[] data,
        int offset,
        int bufferSize)
        throws LineUnavailableException {
        byte[] input = new byte[bufferSize];
        for (int ii=0; ii<input.length; ii++) {
            input[ii] = data[offset+ii];
        }
        ByteArrayInputStream inputStream = new ByteArrayInputStream(input);
        try {
            AudioInputStream ais1 = AudioSystem.getAudioInputStream(inputStream);
            AudioInputStream ais2 = AudioSystem.getAudioInputStream(format, ais1);
            open(ais2);
        } catch( UnsupportedAudioFileException uafe ) {
            throw new IllegalArgumentException(uafe);
        } catch( IOException ioe ) {
            throw new IllegalArgumentException(ioe);
        }
        // TODO    -    throw IAE for invalid frame size, format.
    }

    @Override
    public float getLevel() {
        return dataLine.getLevel();
    }

    @Override
    public long getLongFramePosition() {
        return dataLine.getLongFramePosition()*2/format.getChannels();
    }

    @Override
    public int available() {
        return dataLine.available();
    }

    @Override
    public int getBufferSize() {
        return dataLine.getBufferSize();
    }

    @Override
    public AudioFormat getFormat() {
        return format;
    }

    @Override
    public boolean isActive() {
        return dataLine.isActive();
    }

    @Override
    public boolean isRunning() {
        return dataLine.isRunning();
    }

    @Override
    public boolean isOpen() {
        return dataLine.isOpen();
    }

    @Override
    public void stop() {
        logger.log(Level.FINEST, "BigClip.stop()");
        active = false;
        // why did I have this commented out?
        dataLine.stop();
        if (thread!=null) {
            try {
                active = false;
                thread.join();
            } catch(InterruptedException wakeAndContinue) {
            }
        }
    }

    public byte[] convertMonoToStereo(byte[] data, int bytesRead) {
        byte[] tempData = new byte[bytesRead*2];
        if (format.getSampleSizeInBits()==8) {
            for(int ii=0; ii<bytesRead; ii++) {
                byte b = data[ii];
                tempData[ii*2] = b;
                tempData[ii*2+1] = b;
            }
        } else {
            for(int ii=0; ii<bytesRead-1; ii+=2) {
                //byte b2 = is2.read();
                byte b1 = data[ii];
                byte b2 = data[ii+1];
                tempData[ii*2] = b1;
                tempData[ii*2+1] = b2;
                tempData[ii*2+2] = b1;
                tempData[ii*2+3] = b2;
            }
        }
        return tempData;
    }

    boolean fastForward;
    boolean fastRewind;

    public void setFastForward(boolean fastForward) {
        logger.log(Level.FINEST, "FastForward " + fastForward);
        this.fastForward = fastForward;
        fastRewind = false;
        flush();
    }

    public boolean getFastForward() {
        return fastForward;
    }

    public void setFastRewind(boolean fastRewind) {
        logger.log(Level.FINEST, "FastRewind " + fastRewind);
        this.fastRewind = fastRewind;
        fastForward = false;
        flush();
    }

    public boolean getFastRewind() {
        return fastRewind;
    }

    /** TODO - fix bug in LOOP_CONTINUOUSLY */
    @Override
    public void start() {
        Runnable r = new Runnable() {
            public void run() {
                try {
                    /* Should these open()/close() calls be here, or explicitly
                    called by user program?    The JavaDocs for line suggest that
                    Clip should throw an IllegalArgumentException, so we'll
                    stick with that and call it explicitly. */
                    dataLine.open();

                    dataLine.start();

                    active = true;

                    int bytesRead = 0;
                    int frameSize = dataLine.getFormat().getFrameSize();
                    int bufSize = dataLine.getBufferSize();
                    boolean startOrMove = true;
                    byte[] data = new byte[bufSize];
                    int offset = framePosition*frameSize;
                    int totalBytes = offset;
                    bytesRead = inputStream.read(new byte[offset], 0, offset);
                    logger.log(Level.FINE, "bytesRead " + bytesRead );
                    bytesRead = inputStream.read(data,0,data.length);

                    logger.log(Level.FINE, "loopCount " + loopCount );
                    logger.log(Level.FINE, "countDown " + countDown );
                    logger.log(Level.FINE, "bytesRead " + bytesRead );

                    while (bytesRead != -1 &&
                        (loopCount==Clip.LOOP_CONTINUOUSLY ||
                        countDown>0) &&
                        active ) {
                        logger.log(Level.FINEST,
                            "BigClip.start() loop " + framePosition );
                        totalBytes += bytesRead;
                        int framesRead;
                        byte[] tempData;
                        if (format.getChannels()<2) {
                            tempData = convertMonoToStereo(data, bytesRead);
                            framesRead = bytesRead/
                                format.getFrameSize();
                            bytesRead*=2;
                        } else {
                            framesRead = bytesRead/
                                dataLine.getFormat().getFrameSize();
                            tempData = Arrays.copyOfRange(data, 0, bytesRead);
                        }
                        framePosition += framesRead;
                        if (framePosition>=loopPointEnd) {
                            framePosition = loopPointStart;
                            inputStream.reset();
                            countDown--;
                            logger.log(Level.FINEST,
                                "Loop Count: " + countDown );
                        }
                        timelastPositionSet = System.currentTimeMillis();
                        byte[] newData;
                        if (fastForward) {
                            newData = getEveryNthFrame(tempData, 2);
                        } else if (fastRewind) {
                            byte[] temp = getEveryNthFrame(tempData, 2);
                            newData = reverseFrames(temp);
                            inputStream.reset();
                            totalBytes -= 2*bytesRead;
                        framePosition -= 2*framesRead;
                            if (totalBytes<0) {
                                setFastRewind(false);
                                totalBytes = 0;
                            }
                            inputStream.skip(totalBytes);
                            logger.log(Level.FINE, "totalBytes " + totalBytes);
                        } else {
                            newData = tempData;
                        }
                        dataLine.write(newData, 0, newData.length);
                        if (startOrMove) {
                            data = new byte[bufSize/
                                bufferUpdateFactor];
                            startOrMove = false;
                        }
                        bytesRead = inputStream.read(data,0,data.length);
                        if (bytesRead<0 && countDown-->1) {
                            inputStream.read(new byte[offset], 0, offset);
                            logger.log(Level.FINE, "loopCount " + loopCount );
                            logger.log(Level.FINE, "countDown " + countDown );
                            inputStream.reset();
                            bytesRead = inputStream.read(data,0,data.length);
                        }
                    }
                    logger.log(Level.FINEST,
                        "BigClip.start() loop ENDED" + framePosition );
                    active = false;
                    countDown = 1;
                    framePosition = 0;
                    inputStream.reset();
                    dataLine.drain();
                    dataLine.stop();
                    /* should these open()/close() be here, or explicitly
                    called by user program? */
                    dataLine.close();
                } catch (LineUnavailableException lue) {
                    logger.log( Level.SEVERE,
                        "No sound line available!", lue );
                    if (parent!=null) {
                        JOptionPane.showMessageDialog(
                            parent,
                            "Clear the sound lines to proceed",
                            "No audio lines available!",
                            JOptionPane.ERROR_MESSAGE);
                    }
                }
            }
        };
        thread= new Thread(r);
        // makes thread behaviour compatible with JavaSound post 1.4
        thread.setDaemon(true);
        thread.start();
    }

    /** Assume the frame size is 4. */
    public byte[] reverseFrames(byte[] data) {
        byte[] reversed = new byte[data.length];
        byte[] frame = new byte[4];

        for (int ii=0; ii<data.length/4; ii++) {
            int first = (data.length)-((ii+1)*4)+0;
            int last = (data.length)-((ii+1)*4)+3;
            frame[0] = data[first];
            frame[1] = data[(data.length)-((ii+1)*4)+1];
            frame[2] = data[(data.length)-((ii+1)*4)+2];
            frame[3] = data[last];

            reversed[ii*4+0] = frame[0];
            reversed[ii*4+1] = frame[1];
            reversed[ii*4+2] = frame[2];
            reversed[ii*4+3] = frame[3];
            if (ii<5 || ii>(data.length/4)-5) {
                logger.log(Level.FINER, "From \t" + first + " \tlast " + last );
                logger.log(Level.FINER, "To \t" + ((ii*4)+0) + " \tlast " + ((ii*4)+3) );
            }
        }

/*
        for (int ii=0; ii<data.length; ii++) {
            reversed[ii] = data[data.length-1-ii];
        }
*/

        return reversed;
    }

    /** Assume the frame size is 4. */
    public byte[] getEveryNthFrame(byte[] data, int skip) {
        int length = data.length/skip;
        length = (length/4)*4;
        logger.log(Level.FINEST, "length " + data.length + " \t" + length);
        byte[] b = new byte[length];
        //byte[] frame = new byte[4];
        for (int ii=0; ii<b.length/4; ii++) {
            b[ii*4+0] = data[ii*skip*4+0];
            b[ii*4+1] = data[ii*skip*4+1];
            b[ii*4+2] = data[ii*skip*4+2];
            b[ii*4+3] = data[ii*skip*4+3];
        }
        return b;
    }

    @Override
    public void flush() {
        dataLine.flush();
    }

    @Override
    public void drain() {
        dataLine.drain();
    }

    @Override
    public void removeLineListener(LineListener listener) {
        dataLine.removeLineListener(listener);
    }

    @Override
    public void addLineListener(LineListener listener) {
        dataLine.addLineListener(listener);
    }

    @Override
    public Control getControl(Control.Type control) {
        return dataLine.getControl(control);
    }

    @Override
    public Control[] getControls() {
        if (dataLine==null) {
            return new Control[0];
        } else {
            return dataLine.getControls();
        }
    }

    @Override
    public boolean isControlSupported(Control.Type control) {
        return dataLine.isControlSupported(control);
    }

    @Override
    public void close() {
        dataLine.close();
    }

    @Override
    public void open() throws LineUnavailableException {
        throw new IllegalArgumentException("illegal call to open() in interface Clip");
    }

    @Override
    public Line.Info getLineInfo() {
        return dataLine.getLineInfo();
    }

    /** Determines the single largest sample size of all channels of the current clip.
    This can be handy for determining a fraction to scal visual representations.
    @return Double between 0 & 1 representing the maximum signal level of any channel. */
    public double getLargestSampleSize() {

        int largest = 0;
        int current;

        boolean signed = (format.getEncoding()==AudioFormat.Encoding.PCM_SIGNED);
        int bitDepth = format.getSampleSizeInBits();
        boolean bigEndian = format.isBigEndian();

        int samples = audioData.length*8/bitDepth;

        if (signed) {
            if (bitDepth/8==2) {
                if (bigEndian) {
                    for (int cc = 0; cc < samples; cc++) {
                        current = (audioData[cc*2]*256 + (audioData[cc*2+1] & 0xFF));
                        if (Math.abs(current)>largest) {
                            largest = Math.abs(current);
                        }
                    }
                } else {
                    for (int cc = 0; cc < samples; cc++) {
                        current = (audioData[cc*2+1]*256 + (audioData[cc*2] & 0xFF));
                        if (Math.abs(current)>largest) {
                            largest = Math.abs(current);
                        }
                    }
                }
            } else {
                for (int cc = 0; cc < samples; cc++) {
                    current = (audioData[cc] & 0xFF);
                    if (Math.abs(current)>largest) {
                        largest = Math.abs(current);
                    }
                }
            }
        } else {
            if (bitDepth/8==2) {
                if (bigEndian) {
                    for (int cc = 0; cc < samples; cc++) {
                        current = (audioData[cc*2]*256 + (audioData[cc*2+1] - 0x80));
                        if (Math.abs(current)>largest) {
                            largest = Math.abs(current);
                        }
                    }
                } else {
                    for (int cc = 0; cc < samples; cc++) {
                        current = (audioData[cc*2+1]*256 + (audioData[cc*2] - 0x80));
                        if (Math.abs(current)>largest) {
                            largest = Math.abs(current);
                        }
                    }
                }
            } else {
                for (int cc = 0; cc < samples; cc++) {
                    if ( audioData[cc]>0 ) {
                        current = (audioData[cc] - 0x80);
                        if (Math.abs(current)>largest) {
                            largest = Math.abs(current);
                        }
                    } else {
                        current = (audioData[cc] + 0x80);
                        if (Math.abs(current)>largest) {
                            largest = Math.abs(current);
                        }
                    }
                }
            }
        }

        // audioData
        logger.log(Level.FINEST, "Max signal level: " + (double)largest/(Math.pow(2, bitDepth-1)));
        return (double)largest/(Math.pow(2, bitDepth-1));
    }
}