Android AudioTrack getPlaybackHeadPosition始终返回0

我正在写一些代码,打算采取一个波文件,并写出来和音频跟踪在模式流。这是一个最低可行的测试,使音频跟踪流模式工作。

但是,一旦我向AudioTrack写入一些音频缓冲区,然后调用play(),getPlaybackHeadPosition()方法将持续返回0。

编辑:如果我忽略可用的帧检查,只是不断地向AudioTrack写入缓冲区,write方法返回0(在第一个缓冲区写入之后),表示它只是没有再写入任何音频。看来这首音轨不想开始播放了。

我的代码正确启动了音频曲目。play方法没有抛出任何异常,所以我不确定出了什么问题。

当单步执行代码时,我端上的所有东西都是我预期的那样,所以我在想,不知怎么的,我把音频曲目配置错了。

我在一个模拟器上运行,但我不认为这是一个问题。

我正在使用的WavFile类是一个经过审查的类,我已经在许多Java项目中启动并可靠地运行了它,它经过测试可以很好地工作。

请注意下面的日志写入,这是较大代码块中的一个片段。此日志写入从未命中。。。

                if (headPosition > 0)
                    Log.e("headPosition is greater than zero!!");

..

public static void writeToAudioTrackStream(final WavFile wave) 
    {
    Log.e("writeToAudioTrackStream");

    Thread thread = new Thread()
    {
        public void run()
        {
            try {

                final float[] data = wave.getData();
                int format = -1;

                if (wave.getChannel() == 1)
                    format = AudioFormat.CHANNEL_OUT_MONO;
                else if (wave.getChannel() == 2)
                    format = AudioFormat.CHANNEL_OUT_STEREO;
                else
                    throw new RuntimeException("writeToAudioTrackStatic() - unsupported number of channels value = "+wave.getChannel());

                final int bufferSizeInFrames = 2048;
                final int bytesPerSmp = wave.getBytesPerSmp();
                final int bufferSizeInBytes = bufferSizeInFrames * bytesPerSmp * wave.getChannel();

                AudioTrack audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, wave.getSmpRate(),
                        format,
                        AudioFormat.ENCODING_PCM_FLOAT,
                        bufferSizeInBytes,
                        AudioTrack.MODE_STREAM);

                int index = 0;
                float[] buffer = new float[bufferSizeInFrames * wave.getChannel()];
                boolean started = false;
                int framesWritten = 0;

                while (index < data.length) {

                    // calculate the available space in the buffer
                    int headPosition = audioTrack.getPlaybackHeadPosition();
                    if (headPosition > 0)
                        Log.e("headPosition is greater than zero!!");
                    int framesInBuffer = framesWritten - headPosition;
                    int availableFrames = bufferSizeInFrames - framesInBuffer;

                    // once the buffer has no space, the prime is done, so start playing
                    if (availableFrames == 0) {
                        if (!started) {
                            audioTrack.play();
                            started = true;
                        }
                        continue;
                    }

                    int endOffset = availableFrames * wave.getChannel();

                    for (int i = 0; i < endOffset; i++)
                        buffer[i] = data[index + i];

                    int samplesWritten = audioTrack.write(buffer , 0 , endOffset , AudioTrack.WRITE_BLOCKING);

                    // could return error values
                    if (samplesWritten < 0)
                        throw new RuntimeException("AudioTrack write error.");

                    framesWritten += samplesWritten / wave.getChannel();
                    index = endOffset;
                }
            }
            catch (Exception e) {
                Log.e(e.toString());
            }     
        }
    };

    thread.start();
}