public MP3Stream(Stream stream, bool scanStream, int lengthOffset)
{
int frameLength = 0;
if (scanStream)
_frameInfoCollection = new FrameInfoCollection();
else
_frameInfoCollection = null;
_dataStartIndex = stream.Position;
do
{
_frame = MP3Frame.FromStream(stream);
if (_frame == null && stream.IsEndOfStream())
throw new FormatException("Stream is no MP3-stream. No MP3-Frame was found.");
} while (_frame == null && !stream.IsEndOfStream());
frameLength = _frame.FrameLength;
_sampleRate = _frame.SampleRate;
XingHeader = XingHeader.FromFrame(_frame); //The first frame can contain a Xingheader
if (XingHeader != null)
{
//Todo: dataInitPosition = stream.Position
_dataStartIndex = stream.Position;
}
_dataLength = stream.Length - _dataStartIndex - lengthOffset;
if (scanStream)
{
stream.Position = _dataStartIndex;
PreScanFile(stream);
CanSeek = true;
}
else
{
CanSeek = false;
}
stream.Position = _dataStartIndex;
/*
* bytes * 8 (8bits perbyte) / ms = totalbits / totalms = bits per ms
*/
if (scanStream)
{
_bitRate = ((_dataLength * 8.0) / ((double)_frameInfoCollection.TotalSamples / (double)_sampleRate));
}
else
{
_bitRate = ((_frame.BitRate) / 1);
}
MP3Format = new MP3Format(_sampleRate, _frame.ChannelCount, frameLength, (int)Math.Round(_bitRate));
_converter = new AcmConverter(MP3Format);
WaveFormat = _converter.DestinationFormat;
//_bytesPerSample = (WaveFormat.BitsPerSample / 8 * WaveFormat.Channels);
_pcmDstBuffer = new byte[SamplesPerFrame * WaveFormat.BytesPerBlock * 2];
stream.Position = _dataStartIndex;
_stream = stream;
}
private void BufferProc(object o)
{
if (_stream == null || _stream.CanRead == false)
throw new Exception("Mp3WebStream not initialized");
MP3Frame frame = GetNextFrame(_stream);
int channels = frame.ChannelMode == MP3ChannelMode.Stereo ? 2 : 1;
AcmConverter converter = new AcmConverter(new MP3Format(frame.SampleRate, frame.ChannelCount, frame.FrameLength, frame.BitRate));
_waveFormat = converter.DestinationFormat;
byte[] buffer = new byte[16384 * 4];
_buffer = new FixedSizeBuffer<byte>(converter.DestinationFormat.BytesPerSecond * 10);
ManualResetEvent resetEvent = o as ManualResetEvent;
resetEvent.Set();
do
{
if (_buffer.Buffered >= _buffer.Length * 0.85 && !_disposing)
{
Thread.Sleep(250);
continue;
}
try
{
frame = GetNextFrame(_stream);
//_frameBuffer is set in GetNextFrame
int count = converter.Convert(_frameBuffer, frame.FrameLength, buffer, 0);
if (count > 0)
{
int written = _buffer.Write(buffer, 0, count);
}
}
catch (MmException)
{
_disposing = true;
ThreadPool.QueueUserWorkItem((c) =>
{
while (_bufferThread.ThreadState != System.Threading.ThreadState.Stopped) ;
CreateStream(false);
});
}
catch (WebException)
{
InitializeConnection();
}
catch (IOException)
{
InitializeConnection();
}
} while (!_disposing);
if (converter != null)
converter.Dispose();
}
protected void Dispose(bool disposing)
{
lock (_lockObject)
{
if (disposing)
{
if (_converter != null)
{
_converter.Dispose();
_converter = null;
}
if (_stream != null)
{
_stream.Dispose();
_stream = null;
}
if (_frameInfoCollection != null)
{
_frameInfoCollection.Dispose();
_frameInfoCollection = null;
}
_pcmDstBuffer = null;
_frame = null;
}
}
}
