Question

我正在使用格式：

通过Barix InStreamer 100传输RTP音频流

PCM 16Bit 8kHz Mono（Little endian）

我正在尝试播放＆＃34;实时＆＃34;通过使用自定义MediaStreamSource的MediaElement。问题是我在播放该流时会得到2秒的延迟。在我的电脑上有VLC，有＃34;没有＆＃34;延迟。

我发现，MediaStreamSource有一个属性＆＃34; AudioBufferLength＆＃34;女巫可以设置为15毫秒到1000毫秒之间的值。但是当值太小时，我在GetSampleAsync-＆gt; ReportGetSampleCompleted中有一个例外

这是我的代码：

        protected override void GetSampleAsync(MediaStreamType mediaStreamType)
    {
        Debug.WriteLine("GetSampleAsync called.");

        // Start with one second of data, rounded up to the nearest block.
        var blocksize = (uint)AlignUp(_wavParser.WaveFormatEx.AvgBytesPerSec, _wavParser.WaveFormatEx.BlockAlign);

        var chunkSize = Math.Min(blocksize, (uint)_stream.Length - _currentPosition);
        var chunkDuration = _currentPosition * 10000000L / 8000;  //// _wavParser.WaveFormatEx.AudioDurationFromBufferSize((uint)chunkSize);

        // Send out the next sample
        var chunkSample = new MediaStreamSample(_mediaStreamDescription, _stream, _currentPosition, chunkSize, _currentTimeStamp, chunkDuration, _emptySampleDict);

        // Move our timestamp and position forward

        _currentPosition += chunkSize;
        _currentTimeStamp += chunkDuration;

        ReportGetSampleCompleted(chunkSample);  // <-- There i got a NullRef Ex, when the chunk is too small
    }

这是我如何最初打开媒体：

        protected override void OpenMediaAsync()
    {
        try
        {
            // Create a parser
            _wavParser = new WavParser(_stream);

            // Parse the header
            _wavParser.ParseWaveHeader();
            _wavParser.WaveFormatEx.ValidateWaveFormat();
            _startPosition = _currentPosition = _wavParser.DataPosition;

            // Init
            _streamAttributes = new Dictionary<MediaStreamAttributeKeys, string>();
            _sourceAttributes = new Dictionary<MediaSourceAttributesKeys, string>();
            var availableStreams = new List<MediaStreamDescription>();

            // Stream Description
            _streamAttributes[MediaStreamAttributeKeys.CodecPrivateData] = _wavParser.WaveFormatEx.ToHexString();
            _mediaStreamDescription = new MediaStreamDescription(MediaStreamType.Audio, _streamAttributes);
            availableStreams.Add(_mediaStreamDescription);

            _sourceAttributes[MediaSourceAttributesKeys.Duration] = _wavParser.Duration.ToString();
            ReportOpenMediaCompleted(_sourceAttributes, availableStreams);
        }
        catch (Exception exception)
        {
            Debug.WriteLine("Error while opening media source." + exception.Message);
        }
    }

有人可以给我一个提示吗？或者有更好的方法在WindowsPhone上实时播放RTP / PCM流（8）？请保存我的屁股：）

使用Windows Phone 8应用程序的实时（RTP）音频流

0 个答案: