我遇到与上一个问题相关的问题。我想从混音器（扬声器）录制音频，我正在使用javax.sound。我必须设置audioFormat并且我不知道在那里键入什么：/使用类ListMixer（我在这里找到 - ＆gt; http://forums.oracle.com/forums/thread.jspa?threadID=2198477&tstart=2），我写的是这样的：http://forums.oracle.com/forums/thread.jspa?threadID=2198477&tstart=2但我不喜欢没有关于采样率的任何信息（未知采样率）。程序抛出了这个例外：
java.lang.IllegalArgumentException：Line unsupported：interface TargetDataLine支持格式PCM_UNSIGNED 44100.0 Hz，8位，单声道，4字节/帧，
代码：
package sound;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.sound.sampled.*;
public class AudioCapture02 extends JFrame{
boolean stopCapture = false;
ByteArrayOutputStream byteArrayOutputStream;
AudioFormat audioFormat;
TargetDataLine targetDataLine;
AudioInputStream audioInputStream;
SourceDataLine sourceDataLine;
public AudioCapture02(){//constructor
final JButton captureBtn =
new JButton("Capture");
final JButton stopBtn = new JButton("Stop");
final JButton playBtn =
new JButton("Playback");
captureBtn.setEnabled(true);
stopBtn.setEnabled(false);
playBtn.setEnabled(false);
//Register anonymous listeners
captureBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
captureBtn.setEnabled(false);
stopBtn.setEnabled(true);
playBtn.setEnabled(false);
//Capture input data from the
// microphone until the Stop button is
// clicked.
captureAudio();
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
getContentPane().add(captureBtn);
stopBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
captureBtn.setEnabled(true);
stopBtn.setEnabled(false);
playBtn.setEnabled(true);
//Terminate the capturing of input data
// from the microphone.
stopCapture = true;
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
getContentPane().add(stopBtn);
playBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
//Play back all of the data that was
// saved during capture.
playAudio();
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
getContentPane().add(playBtn);
getContentPane().setLayout(new FlowLayout());
setTitle("Capture/Playback Demo");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(250,70);
setVisible(true);
}//end constructor
//This method captures audio input from a
// microphone and saves it in a
// ByteArrayOutputStream object.
private void captureAudio(){
try{
//Get and display a list of
// available mixers.
Mixer.Info[] mixerInfo = AudioSystem.getMixerInfo();
System.out.println("Available mixers:");
for(int cnt = 0; cnt < mixerInfo.length;
cnt++){
System.out.println(mixerInfo[cnt].
getName());
}//end for loop
//Get everything set up for capture
audioFormat = new AudioFormat(AudioFormat.Encoding.PCM_UNSIGNED, 44100.0F, 8, 1, 4, 44100.0F,
false);
DataLine.Info dataLineInfo =
new DataLine.Info(
TargetDataLine.class,
audioFormat);
ListMixers lm = new ListMixers();
lm.listAll(new PrintWriter(System.out));
System.out.println(" AKTUALNY => "+mixerInfo[0].getName());
Mixer mixer = AudioSystem.getMixer(mixerInfo[0]);
//Get a TargetDataLine on the selected
// mixer.
targetDataLine = (TargetDataLine)
mixer.getLine(dataLineInfo);
//Prepare the line for use.
targetDataLine.open(audioFormat);
targetDataLine.start();
//Create a thread to capture the microphone
// data and start it running. It will run
// until the Stop button is clicked.
Thread captureThread = new CaptureThread();
captureThread.start();
} catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end captureAudio method
//This method plays back the audio data that
// has been saved in the ByteArrayOutputStream
private void playAudio() {
try{
//Get everything set up for playback.
//Get the previously-saved data into a byte
// array object.
byte audioData[] = byteArrayOutputStream.
toByteArray();
//Get an input stream on the byte array
// containing the data
InputStream byteArrayInputStream =
new ByteArrayInputStream(audioData);
AudioFormat audioFormat = getAudioFormat();
audioInputStream = new AudioInputStream(
byteArrayInputStream,
audioFormat,
audioData.length/audioFormat.
getFrameSize());
DataLine.Info dataLineInfo =
new DataLine.Info(
SourceDataLine.class,
audioFormat);
sourceDataLine = (SourceDataLine)
AudioSystem.getLine(dataLineInfo);
sourceDataLine.open(audioFormat);
sourceDataLine.start();
//Create a thread to play back the data and
// start it running. It will run until
// all the data has been played back.
Thread playThread = new PlayThread();
playThread.start();
} catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end playAudio
//This method creates and returns an
// AudioFormat object for a given set of format
// parameters. If these parameters don't work
// well for you, try some of the other
// allowable parameter values, which are shown
// in comments following the declartions.
private AudioFormat getAudioFormat(){
float sampleRate = 8000.0F;
//8000,11025,16000,22050,44100
int sampleSizeInBits = 16;
//8,16
int channels = 1;
//1,2
boolean signed = true;
//true,false
boolean bigEndian = false;
//true,false
return new AudioFormat(
sampleRate,
sampleSizeInBits,
channels,
signed,
bigEndian);
}//end getAudioFormat
//=============================================//
//Inner class to capture data from microphone
class CaptureThread extends Thread{
//An arbitrary-size temporary holding buffer
byte tempBuffer[] = new byte[10000];
public void run(){
byteArrayOutputStream =
new ByteArrayOutputStream();
stopCapture = false;
try{//Loop until stopCapture is set by
// another thread that services the Stop
// button.
while(!stopCapture){
//Read data from the internal buffer of
// the data line.
int cnt = targetDataLine.read(tempBuffer,
0,
tempBuffer.length);
if(cnt > 0){
//Save data in output stream object.
byteArrayOutputStream.write(tempBuffer,
0,
cnt);
}//end if
}//end while
byteArrayOutputStream.close();
}catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end run
}//end inner class CaptureThread
//===================================//
//Inner class to play back the data
// that was saved.
class PlayThread extends Thread{
byte tempBuffer[] = new byte[10000];
public void run(){
try{
int cnt;
//Keep looping until the input read method
// returns -1 for empty stream.
while((cnt = audioInputStream.read(
tempBuffer, 0,
tempBuffer.length)) != -1){
if(cnt > 0){
//Write data to the internal buffer of
// the data line where it will be
// delivered to the speaker.
sourceDataLine.write(tempBuffer,0,cnt);
}//end if
}//end while
//Block and wait for internal buffer of the
// data line to empty.
sourceDataLine.drain();
sourceDataLine.close();
}catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end run
}//end inner class PlayThread
//=============================================//
class ListMixers {
PrintWriter out;
void listAll(final PrintWriter out) {
this.out = out;
Mixer.Info[] aInfos = AudioSystem.getMixerInfo();
for (int i = 0; i < aInfos.length; i++) {
try {
Mixer mixer = AudioSystem.getMixer(aInfos[i]);
out.println(""+i+": "+aInfos[i].getName()+", "
+aInfos[i].getVendor()+", "
+aInfos[i].getVersion()+", "
+aInfos[i].getDescription());
printLines(mixer, mixer.getSourceLineInfo());
printLines(mixer, mixer.getTargetLineInfo());
} catch (Exception e) {
out.println("Exception: "+e);
}
out.println();
}
if (aInfos.length == 0) {
out.println("[No mixers available]");
}
}
void printLines(Mixer mixer, Line.Info[] infos) {
for (int i = 0; i < infos.length; i++) {
try {
if (infos[i] instanceof Port.Info) {
Port.Info info = (Port.Info) infos[i];
out.println(" Port " + info);
}
if (infos[i] instanceof DataLine.Info) {
DataLine.Info info = (DataLine.Info) infos[i];
out.println(" Line " + info + " (max. " +
mixer.getMaxLines(info) + " simultaneously): ");
printFormats(info);
}
Line line = mixer.getLine(infos[i]);
if (!(line instanceof Clip)) {
try {
line.open();
}
catch (LineUnavailableException e) {
out.println("LineUnavailableException when trying to open this line");
}
}
try {
printControls(line.getControls());
}
finally {
if (!(line instanceof Clip)) {
line.close();
}
}
}
catch (Exception e) {
out.println("Exception: " + e);
}
out.println();
}
}
void printFormats(DataLine.Info info) {
AudioFormat[] formats = info.getFormats();
for (int i = 0; i < formats.length; i++) {
out.println(" "+i+": "+formats[i]
+" ("+formats[i].getChannels()+" channels, "
+"frameSize="+formats[i].getFrameSize()+", "
+(formats[i].isBigEndian()?"big endian":"little endian")
+")");
}
if (formats.length == 0) {
out.println(" [no formats]");
}
out.println();
}
void printControls(Control[] controls) {
for (int i = 0; i<controls.length; i++) {
printControl(" ", "Controls["+i+"]: ", controls[i]);
}
if (controls.length == 0) {
out.println(" [no controls]");
}
out.println();
}
void printControl(String indent, String id, Control control) {
if (control instanceof BooleanControl) {
BooleanControl ctrl = (BooleanControl) control;
out.println(indent+id+"BooleanControl: "+ctrl);
} else if (control instanceof CompoundControl) {
CompoundControl ctrl = (CompoundControl) control;
Control[] ctrls = ctrl.getMemberControls();
out.println(indent+id+"CompoundControl: "+control);
for (int i=0; i<ctrls.length; i++) {
printControl(indent+" ", "MemberControls["+i+"]: ", ctrls[i]);
}
} else if (control instanceof EnumControl) {
EnumControl ctrl = (EnumControl) control;
Object[] values = ctrl.getValues();
Object value = ctrl.getValue();
out.println(indent+id+"EnumControl: "+control);
for (int i=0; i<values.length; i++) {
if (values[i] instanceof Control) {
printControl(indent+" ", "Values["+i+"]: "+((values[i]==value)?"*":""), (Control) values[i]);
} else {
out.println(indent+" Values["+i+"]: "+((values[i]==value)?"*":"")+values[i]);
}
}
} else if (control instanceof FloatControl) {
FloatControl ctrl = (FloatControl) control;
out.println(indent+id+"FloatControl: "+ctrl);
} else {
out.println(indent+id+"Control: "+control);
}
}
}
}//end outer class AudioCapture02.java
答案 0 :(得分：9)
您正在使用您创建的AudioFormat获取TargetDataLine。这不保证有效。您必须先使用AudioSystem.isLineSupported(Info info)方法查询调音台以检查它是否支持您所需的AudioFormat。
就个人而言，我觉得这很麻烦。您需要查询系统上的混音器以确定它们是否支持您想要的AudioFormat。
下面的函数将获得数据行类支持格式的Vector。使用
调用它Vector<AudioFormat> formats = getSupportedFormats(TargetDataLine.class);
或
Vector<AudioFormat> formats = getSupportedFormats(SourceDataLine.class);
此代码可能需要一些调试;我不得不删除一些特定于应用程序的东西，使其自包含......
public Vector<AudioFormat> getSupportedFormats(Class<?> dataLineClass) {
/*
* These define our criteria when searching for formats supported
* by Mixers on the system.
*/
float sampleRates[] = { (float) 8000.0, (float) 16000.0, (float) 44100.0 };
int channels[] = { 1, 2 };
int bytesPerSample[] = { 2 };
AudioFormat format;
DataLine.Info lineInfo;
SystemAudioProfile profile = new SystemAudioProfile(); // Used for allocating MixerDetails below.
Vector<AudioFormat> formats = new Vector<AudioFormat>();
for (Mixer.Info mixerInfo : AudioSystem.getMixerInfo()) {
for (int a = 0; a < sampleRates.length; a++) {
for (int b = 0; b < channels.length; b++) {
for (int c = 0; c < bytesPerSample.length; c++) {
format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
sampleRates[a], 8 * bytesPerSample[c], channels[b], bytesPerSample[c],
sampleRates[a], false);
lineInfo = new DataLine.Info(dataLineClass, format);
if (AudioSystem.isLineSupported(lineInfo)) {
/*
* TODO: To perform an exhaustive search on supported lines, we should open
* TODO: each Mixer and get the supported lines. Do this if this approach
* TODO: doesn't give decent results. For the moment, we just work with whatever
* TODO: the unopened mixers tell us.
*/
if (AudioSystem.getMixer(mixerInfo).isLineSupported(lineInfo)) {
formats.add(format);
}
}
}
}
}
}
return formats;
}
答案 1 :(得分：7)
可以直接获得所有支持的Lines及其AudioFormats。我是为系统上默认SourceDataLines的{{1}}执行此操作的，您可以轻松编辑代码，以获得任何Mixer和Lines支持1}}。
AudioFormats我得到这样的输出：
Mixer