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javastreamaudio

Play WAV file backward


I'm making Braid in Java. If you rewind the time, the sound plays backward. How can I play a WAV file backward? Maybe with a stream with something like previous()? On the site of Braid can you see what I mean.


Solution

  • I solved it by myself

    import java.io.IOException;
    import javax.sound.sampled.AudioInputStream;
    
    /**
     *
     * @author Martijn
     */
    public class FrameBuffer {
    
        private byte[][] frames;
        private int frameSize;
    
        public FrameBuffer(AudioInputStream stream) throws IOException {
            readFrames(stream);
        }
    
        public byte[] getFrame(int i) {
            return frames[i];
        }
    
        public int numberFrames()
        {
            return frames.length;
        }
    
        public int frameSize()
        {
            return frameSize;
        }
    
        private void readFrames(AudioInputStream stream) throws IOException {
            frameSize = stream.getFormat().getFrameSize();
            frames = new byte[stream.available() / frameSize][frameSize];
            int i = 0;
            for (; i < frames.length; i++)
            {
                byte[] frame = new byte[frameSize];
                int numBytes = stream.read(frame, 0, frameSize);
                if (numBytes == -1)
                {
                    break;
                }
                frames[i] = frame;
            }
            System.out.println("FrameSize = " + frameSize);
            System.out.println("Number frames = " + frames.length);
            System.out.println("Number frames read = " + i);
        }
    }
    

    And then:

     FrameBuffer frameStream = new FrameBuffer(austream); //austream is the audiostream
     int frame = frameStream.numberFrames() - 1;
     while (frame >= 0) {
          auline.write(frameStream.getFrame(frame), 0, frameStream.frameSize());
          frame--;
     }