原创 java audio例程分析记录

JavaSound示例程序CapturePlayback.java理解。

import java.io.*;

import javax.sound.sampled.*;

Java播放音频：

SourceDataLine line;

AudioFormat format = formatControls.getFormat();

DataLine.Info info = new DataLine.Info(SourceDataLine.class, format);

line = (SourceDataLine) AudioSystem.getLine(info);

line.open(format, bufSize);

line.start();

line.write(pData, 0, numBytesRemaining);

line.drain();

line.stop();

line.close();

Java录音：

TargetDataLine line;

AudioFormat format = formatControls.getFormat();

DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);

line = (TargetDataLine) AudioSystem.getLine(info);

line.open(format, line.getBufferSize());

line.start();

numBytesRead = line.read(data, 0, bufferLengthInBytes));

line.stop();

line.close();

音频格式转换：

AudioFormat format = formatControls.getFormat();

AudioInputStream playbackInputStream = AudioSystem.getAudioInputStream(format, audioInputStream);

字节数组生成OutputStream：

ByteArrayOutputStream out = new ByteArrayOutputStream();

byte[] data = new byte[bufferLengthInBytes];

out.write(data, 0, numBytesRead);

字节数组生成InputStream：

byte audioBytes[] = out.toByteArray();

ByteArrayInputStream bais = new ByteArrayInputStream(audioBytes);

audioInputStream = new AudioInputStream(bais, format, audioBytes.length / frameSizeInBytes);

文件生成AudioInputStream：

audioInputStream = AudioSystem.getAudioInputStream(file);

AudioInputStream保存到文件：

        File file = new File(fileName = name);

        try {

            if (AudioSystem.write(audioInputStream, fileType, file) == -1) {

                throw new IOException("Problems writing to file");

            }

        } catch (Exception ex) { reportStatus(ex.toString()); }

音频格式设置：

            AudioFormat.Encoding encoding = AudioFormat.Encoding.ULAW;

                encoding = AudioFormat.Encoding.PCM_SIGNED;

                encoding = AudioFormat.Encoding.PCM_UNSIGNED;

                encoding = AudioFormat.Encoding.ALAW;

            return new AudioFormat(encoding, rate, sampleSize,

                          channels, (sampleSize/8)*channels, rate, bigEndian);