我有一个立体声波文件,我只需要读取和播放所选的通道。做到这一点的最佳方法是什么?
当您通过AudioInputStream导入wav文件时,请使用AudioFileFormat信息将字节转换为PCM。左右的数据交替出现。因此,如果该行是16位,则每帧将有4个字节。前两个将组装到左侧通道中,后两个将组装在右侧通道中。 (反之亦然,我很难确定哪个频道是左侧还是右侧。)
这是一个很好的教程,其中包含有关如何读取一行的示例:http://docs.oracle.com/javase/tutorial/sound/converters.html
可能需要本教程中的一些较早的教程来帮助阐明。另外,如果您对将字节转换为PCM有疑问,请在StackOverflow上进行一些解释以供参考。应该不太难找到它们。
这是从多通道直接音频线路(JavaSound)中提取单个通道的简单方法。在我的Line6(r)Helix(r)吉他音效板(8通道)中进行了尝试,效果很好。我猜它可以与任何类型的DataTargetLine一起使用。在这种情况下,我们基于假设16位样本的AudioFormat处理数据。希望对您有所帮助。
public ArrayList<byte[]> extract16BitsSingleChannels(byte[] audioBuffer, int channels) {
/* Parameters :
*
* audioBuffer : the buffer that has just been produced by
* your targetDataLine.read();
* channels : the number of channels defined in the AudioFormat you
* use with the line
*
* the AudioFormat which i tested :
* float sampleRate = 44100;
* int sampleSizeInBits = 16;
* int channels = 8;
* boolean signed = true;
* boolean bigEndian = true;
*/
/* let's create a simple container which will receive our channels buffers */
ArrayList<byte[]> channelsData = new ArrayList<byte[]>();
/* take care of adjusting the size of each channel buffer */
final int channelLength=audioBuffer.length/channels;
/* let's create one buffer per channel and place them in the container */
for (int channelIndex=0 ; channelIndex<channels ;channelIndex++)
{
byte[] channel=new byte[channelLength];
channelsData.add(channel);
}
/* then process bytes and copy each channels byte in its buffer */
int index=0;
for(int i = 0; i < channelLength; i+=2) //i+=2 for 16 bits=2 Bytes samples
{
for (int c=0 ; c < channels ; c++) {
channelsData.get(c)[i]=audioBuffer[index]; // 1st Byte
index++;
channelsData.get(c)[i+1]=audioBuffer[index]; // 2nd Byte
index++;
}
}
/* Returns each set of bytes of each channel in its buffer you can use to
write on whatever Byte streamer you like. */
return channelsData;
}