切割波形文件


问题内容

如何.wave使用Java 剪切文件?

我想要的是:

当用户按下标cut有按钮的按钮时,应将音频从前一个mark(以纳秒为单位)剪切到当前位置(以纳秒为单位)。
(在剪切声音后,标记被定位到当前位置(以纳秒为单位)) 当我获得一段音频后,我想保存该段音频文件。

// obtain an audio stream 
long mark = 0; // initially set to zero
//get the current position in nanoseconds
// after that how to proceed ?
// another method ?

我怎样才能做到这一点 ?


问题答案:

最初由Martin Dow回答

import java.io.*;
import javax.sound.sampled.*;

class AudioFileProcessor {

public static void main(String[] args) {
  copyAudio("/tmp/uke.wav", "/tmp/uke-shortened.wav", 2, 1);
}

public static void copyAudio(String sourceFileName, String destinationFileName, int startSecond, int secondsToCopy) {
AudioInputStream inputStream = null;
AudioInputStream shortenedStream = null;
try {
  File file = new File(sourceFileName);
  AudioFileFormat fileFormat = AudioSystem.getAudioFileFormat(file);
  AudioFormat format = fileFormat.getFormat();
  inputStream = AudioSystem.getAudioInputStream(file);
  int bytesPerSecond = format.getFrameSize() * (int)format.getFrameRate();
  inputStream.skip(startSecond * bytesPerSecond);
  long framesOfAudioToCopy = secondsToCopy * (int)format.getFrameRate();
  shortenedStream = new AudioInputStream(inputStream, format, framesOfAudioToCopy);
  File destinationFile = new File(destinationFileName);
  AudioSystem.write(shortenedStream, fileFormat.getType(), destinationFile);
} catch (Exception e) {
  println(e);
} finally {
  if (inputStream != null) try { inputStream.close(); } catch (Exception e) { println(e); }
  if (shortenedStream != null) try { shortenedStream.close(); } catch (Exception e) { println(e); }
 }
}

}